UROLOGY AN INTRODUCTORY SYLLABUS
Steven H. Selman, M.D. Department of Urology University of Toledo College of Medicine
Introduction. During your rotation on the urologic surgery service you will encounter a spectrum of disease which will introduce you to the science and practice of urology. As in other medical disciplines, urology requires a lifelong commitment to learning. Although it cannot cover all aspects of the specialty, it is hoped this introductory syllabus will serve as a useful reference as you progress through the clerkship. ADRENAL GLAND Clinical Anatomy. Paired endocrine organs, the adrenals are found immediately underneath the diaphragm closely associated with the kidneys. Their shape is somewhat triangular and they have a characteristic golden yellow appearance. The principal products of the adrenals are aldosterone, corticosteroids, epinephrine and norepinephrine. For the urologic surgeon, one of the salient surgical anatomic consideration is the right adrenal vein which is short and drains directly into the inferior vena cava. The left vein drains directly into the Adrenal Anatomy left renal Note short right renal vein. vein. The adrenals can be easily separated from the kidneys during surgical dissection.
Left Adrenal Gland
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Clinical Pathology. Adrenal tumors. The adrenal gland has two components: the cortex and the medulla. The cortex is responsible for the production of glucocorticoids and aldosterone. Overproduction of glucocorticoids by adrenal tumors leads to Cushing's syndrome while overproduction of aldosterone leads to hypertension. Aldosterone secreting tumors are usually discovered during the evaluation of the patient with the rapid onset of hypertension. As aldosterone secretion leads to renal loss of potassium, these patients are often hypokalemic. Aldosteronomas are usually small and almost never malignant. Glucocorticoid secreting tumors may result in Cushing's syndrome. It should be remembered that pituitary tumors can lead to glucocorticoid overproduction and thus the underlying pathology must be determined for proper treatment. Differentiation between the two can be done with dexamethasone suppression testing. Cortical tumors may be malignant. The aggressiveness of these tumors is often difficult to assess histologically and can be determined only by following the patient's clinical course. The adrenal medulla produces epinephrine and norepinephrine, the flight and Left adrenal mass fright hormones. In the adult, tumors of the adrenal medulla are called pheochromocytomas. These tumors can result in a clinical spectrum including tachycardia, flushing and hypertension. Urologic management. Adrenal Tumors. The first step in the management of the patient with suspected adrenal pathology is the establishment of a diagnosis. Tumors of the adrenal cortex may be functioning or non-functioning. Non-functioning tumors are usually discovered incidentally during CT scanning of the retroperitoneum. Occasionally, specialized radiographic techniques are needed to localize adrenal pathology. An example of this is adrenal vein sampling for localization of a small aldosterone secreting adenoma. In general, nonfunctioning tumors of the adrenal of less than 4cm are managed nonoperatively. The rate of CT contrast “wash out” can be used as a criteria for malignancy or serial CT 's are
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used to monitor size. A small number will increase in size and removal is required. The treatment for functioning adrenal Pheochromocytoma tumors is surgical removal. These tumors can Preop be removed either by an open surgical or -Blockade laparoscopic technique . Patients with Volume expansion pheochromocytomas need preoperative intravascular volume expansion since many have decreased intravascular volumes. Blockade of vascular system's alpha receptors is also an important adjunct to the preoperative management of these patients.
KIDNEY Clinical Anatomy. The kidneys normally lie high in the retroperitoneum within the strong but thin Gerota's fascia. A thick layer of adipose tissue within Gerota's fascia surrounds each kidney. The capsule of the kidney lying immediately below this fatty layer gives a greyish-red hue to renal cortex. The parenchyma of the kidney invaginates medially at the renal hilus where the renal artery and vein and pelvis are located. In general, a single renal artery and vein supply the parenchyma of the kidney although Renal segmental arteries multiple arteries or are end arteries. veins are not uncommon. It is important to remember that the renal artery and its branches are "end" arteries meaning that there is no arterial collateral supply within the kidney. Ligation of a branch of the renal artery will lead to loss of renal parenchyma supplied by that artery. The renal pelvis lies posterior to the renal artery and Pelvic Kidney vein fanning out within the renal hilus to form the intrarenal collecting system, i.e. renal calyces. The pelvis narrows as it joins the ureter at the ureteropelvic junction. Occasionally, the kidney will fail to reach its usual anatomic position during embryogenesis, resulting in an ectopic kidney.
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Clinical Pathology. Renal Failure. Failure to excrete the body's products of cellular metabolism through the kidneys leads to the clinical syndrome known as renal insufficiency or failure. Renal failure may be either acute, which is reversible or chronic, which is not.
Urologic Management. Acute renal failure. Bilateral or in the case of a solitary kidney unilateral obstruction can lead to acute renal failure. In such situations, rapid diagnosis and relief of obstruction will correct the problem. Renal ultrasound demonstrating hydronephrosis is helpful in establishing the diagnosis of obstruction. Should ultrasound prove equivocal or the index of suspicion be high, cystoscopy and retrograde pyelography can establish the diagnosis, etiology and site of obstruction. If obstruction is the cause of acute renal Bilateral failure, intervention should be undertaken Hydronephrosis either via endoscopic (stents or ureteral catheters) or percutaneous (nephrostomy) approach.
Urologic Management. Chronic renal failure. Renal transplantation. Chronic renal failure is a debilitating disease. Both hemodialysis and peritoneal dialysis can correct the Renal transplant after completion of electrolyte and metabolic engraftment problems associated with chronic renal failure, but they do not restore full health and vigor. Renal transplantation, although not without risks, comes closest to restoring the patient to a normal and healthy lifestyle. The majority of renal transplants performed throughout the world are cadaveric transplants. Kidneys are removed from beating heart donors whose death has been established by brain death criteria and at times from donors who have sustained cardiac death (DCD donors). The removal of kidneys is usually accompanied by the removal of other
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transplantable organs such as liver, heart, pancreas and lungs. Once the kidneys are removed, they are flushed with a cold storage solution and packed in ice until transplantation. A suitable donor is determined by blood type: (A,B,O), histocompatability: HLA matching, and a serologic “cross match” for circulating anti-HLA antibodies against the donor's lymphocytes in the potential recipient’s serum. A positive cross match (presence of anti-HLA antibodies against the donor's lymphocytes) is a contraindication to transplantation since hyperacute rejection would ensue. Ideally, transplantation of the kidney should occur within 24 hours of removal to minimize storage injury and resultant non-function. Once a suitable recipient is found, transplantation is undertaken by anastomosing Transplant the renal artery to the external or internal iliac artery and the renal vein to the ABO Compatible external iliac vein. The ureter is then HLA Match implanted within the bladder. Usually nothing Lymphocyte is done to the native kidneys during the Crossmatch procedure. Immunosuppression is instituted in the post transplant period with drugs aimed at suppressing the T-cell response to foreign antigen. The principal immunosuppressive drugs are classified as calcinuern blockers and include tacrolimus (FK 506, Prograf™) and cyclosporine (Neoral™), drugs which block the IL-2 receptors on the T-cell. These drugs are usually used in combination with prednisone, a combination which has markedly decreased the incidence of rejection in the postoperative period. Cyclosporine and tacrolimus, however, are nephrotoxic and serum levels must be kept in the therapeutic range to prevent renal dysfunction. In some situations Immunosuppressives other immunosuppressive Prednisone medications must be used either to Cyclosporine reverse the rejection process Tacrolimus (FK 506) should it occur or replace the Mycophenolate Mofetil calcineurin blockers because of OKT3 (Monoclonal) untoward side effects. OKT3 (a Basiliximab (Monoclonal) monoclonal antibody preparation Sirolimus binding to the CD3 Campath (Monoclonal) site),Basiliximab (a monoclonal binding to the IL-2 receptor), and mycophenolate mofetil (Cellcept™, blocks IMP dehydrogenase),sirolimus (Rapamycin) are among the immunosuppressive agents currently available.Some transplant centers have initiated programs using Campath™ a monoclonal antibody directed at CD58. This results in profound lymphopenia over a protracted time. This agent has been used in order to spare patients from steroids. Living related or non related donation is another approach to renal transplantation. As with cadaveric transplantation, blood type between donor and recipient must be compatible. Living related donors may share all, half or
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none of the HLA antigens. Perfect HLA matches between siblings have the best chance for long term graft survival. Non-related donors have no greater chance of sharing common HLA antigens but kidneys obtained via this approach have little risk of sustaining injury from prolonged cold storage since implantation is completed within an hour of removal. Laparoscopic removal of the kidney has increased the willingness of patients to undergo this procedure. A novel program referred to as paired exchange allows for the “swapping” of kidneys between pairs of donors who otherwise would be immunologically incompatible.
Clinical Pathology. Renal lithiasis. Renal lithiasis has its peak incidence between the ages of 20 and 30 but can be encountered at any age. Renal stones cause pain, infection and loss of renal function. The more commonly encountered stones are described below. Calcium oxalate and calcium phosphate stones account for the largest percentage of stones in industrialized countries. Although the majority are "idiopathic" (a relative term since many may be caused by renal tubular leak of calcium or increased calcium absorption by the gut), these stones may result from pathologic conditions resulting in hypercalcemia and Right renal hypercalcuria (e.g., parathyroid adenomas, calculus sarcoidosis) or intrinsic renal problems (e.g. renal tubular acidosis). When over 2mm, o calcium stones are detectable as "radiopaque" densities on non-contrast radiographs. Uric acid calculi are the second most common type of renal calculi Uric Acid encountered in the United States. These stones are "radiolucent" meaning that pH<5 they will not be detected on nonRadiolucent contrasted radiographs. Most commonly, they occur in patients who produce a persistently acid (pH<5) urine. This pH favors the nonionized form of uric acid (a weak acid) which has a much lower solubility product than the ionized form.
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Infection stones composed of magnesium ammonium phosphate result from persistent infection with urea splitting bacteria. A high urinary pH Infection is an associated finding. Infection Mg(NH4 )(PO4) stones (as well as other types of stones) may become large filling the entire renal collecting system resulting in a "staghorn" appearance. A renal tubular defect in the reabsorption of the amino acid cystine leads to the formation of cystine stones. Reabsorption of the Large Staghorn Calculus in the amino acids Left Kidney. ornithine, Cystine arginine, and lysine is also defective in patients who form cystine stone but these Cystine amino acids are soluble. The tubular Ornithine defect in cystinuric patients is an Lysine inheritable, autosomal recessive trait. Arginine Cystine stones are radiodense but less so (COLA) than calcium containing stones making them more difficult to detect on noncontrasted radiographs. This type of stone is the most common of the pediatric age group. CT without contrast has become the imaging modality of choice for the diagnosis of renal stones Urologic Management. Renal lithiasis. The urologic management of renal lithiasis must take into consideration a broad range of clinical information including stone size and composition, location, and the overall medical Renal Stone Management condition of the patient. Small nonobstructing stones may be treated Expectant expectantly in some patients while in Chemolysis others (e.g. airline pilots) treatment ESWL may need to be more aggressive. Percutaneous Treatment options include: Open Surgery Expectant management. Small stones not associated with pain, infection, high grade obstruction or loss of renal parenchyma may be treated "expectantly". Serial plain radiographs are obtained to document stability of stone size. Should increase occur or the status of the stone change otherwise, intervention may be considered. Chemolysis refers to the administration of agents which result in stone dissolution. Uric acid stones are the most
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amenable to this approach. Either oral or intravenous administration of alkalinating agents raise the urinary pH above the pKA of uric acid. This usually results in rapid stone dissolution. Extracorporeal shock wave lithotripsy (ESWL) introduced into clinical practice in the 1980's, revolutionized stone management. Shock waves generated by an underwater extracorporeal high voltage electrical discharge are focused onto the stone with the aid of biplanar ESWL fluoroscopy as the Patient positioned under water. patient lies Shock wave generator under suspended in a tub of patient. water. Fragmentation results from the pressure waves created by the Lithotriptor tub absorbed energy. Small with caliber fragments created fluoroscopic by fragmentation then pass tubes through the genitourinary system. The main limitation to this approach is that the number of fragments created by treatment of larger stones can lead to complications such as “Spark plug” generates obstruction of the ureter. Modern shock wave lithotripters are more compact than pictured above and operate without need for a water bath.
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Percutaneous nephrolithostomy (“Perc”) is more invasive than ESWL in the treatment of stones of the upper collecting system. This approach is an outgrowth of the Seldinger angio access technique in which entry into the calyceal collecting system is attained by percutaneous introduction of a fine needle under radiographic guidance. A guide wire is then placed through the needle. The needle then is withdrawn. The guidewire serves as Percutaneous "railway" over which successively larger approach dilators are placed through the skin, fascia and renal parenchyma. Eventually an opening is created which is large enough to accommodate a nephroscope through which instruments can be passed for stone removal. The majority of stones in the kidney and upper ureter can be managed with the above approaches either as a single treatment option or in combination. A small percentage of cases require open surgery. When necessary, the kidney is approached through the flank an approach optimizing the exposure of the renal pelvis which is opened to gain access to the stone. Large staghorn calculi may require bivalving of the kidney for complete removal. Once stones are removed, they are sent for chemical analysis. When possible, medical management is instituted to prevent recurrence. The foundation of all medical management is hydration. In addition, patients with uric acid stones are treated with oral alkalinizing agents such as potassium citrate. This agent is also useful in the treatment of patients with calcium oxalate stones since citrate is a good binder of calcium. Although limiting intake of calcium rich foods used to be encouraged, epidemiologic studies have shown that individuals on a low calcium diet have an increased tendency for stone formation.
Clinical Pathology. Renal Infection. A number of inflammatory processes can involve the kidneys. Bacterial pyelonephritis is a commonly encountered clinical entity. Flank pain, fever and malaise are the usual presenting symptoms. Occasionally, suppurative bacterial infections will result from untreated pyelonephritis and lead to a renal abscess. Nonbacterial infections, at least in the United States, are usually fungal in orgin, candida albicans being encountered most frequently. Renal infections are complicated by obstruction must be urgently treated to prevent the development of overwhelming sepsis.
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Urologic management. Renal infections. Bacterial infections, uncomplicated by the presence of stone or collecting system obstruction, can usually be managed with intravenous antibiotics and hydration until the clinical course shows improvement. Patients presenting with recurrent infections are evaluated for anatomic abnormalities such as ureterovesical reflux, collecting system obstruction or renal lithiasis. Fungal infections are usually encountered in patients with other serious medical problems and thus treatment must be individualized. Prolonged antimicrobial therapy especially in the presence of an indwelling foreign body(e.g. ureteral stent) dispose the patient to fungal infections. The treatment of a renal abscess is adequate drainage. Percutaneous drainage may be effective and is less morbid than an open surgical approach. As mentioned above, infection complicating collecting system obstruction is a urologic emergency and must be addressed as soon as the diagnosis is established. Treatment consists of relieving the obstruction either percutaneously (percutaneous nephrostomy) or endoscopically (retrograde placement of stents) in addition to support of the patient with fluids and antibiotics. Clinical pathology. Renal neoplasms. Of the malignant renal neoplasms, adenocarcinoma, arising from the proximal renal tubule cell is the most frequently encountered. These cancers are also referred to as hypernephromas, clear cell carcinomas, renal cell carcinomas. Less frequently encountered, although by no means rare, are carcinomas arising from the epithelium of the intrarenal collecting system, transitional cell carcinomas of the kidney. Malignant neoplasms originating in the fibrous connective tissue within the kidney, renal sarcomas are very uncommon. Because of Hypernephroma their retroperitoneal location, renal neoplasms may be large and advanced before they are detected clinically. Renal cell carcinomas have a tendency to invade the renal venous system extending into the renal vein, vena cava and occasionally into the right atrium. Other types of renal cell cancers include papillary, medullary and chromophobe cancers. Multiple renal cell carcinomas may be associated with genetic abnormalities such as seen with von Hipple Lindau (VHL) disease.
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Renal cysts, benign renal tumors, are extremely common. In autopsy studies, as many as 50% of patients, 50 years and older, have been found to harbor renal cysts. Rarely, will these cysts grow to sufficient size to create clinical problems. Differentiating the benign cyst from the cystic renal neoplasm is the principal clinical issue associated with these benign growths. Multiple renal cysts occurring as an autosomal dominant renal disease, adult polycystic kidney disease, may lead to renal failure. Angiomyolipomas are another benign tumor of the kidney. The solid nature of these lesions comprised of angiomatous, myomatous and Right Renal Cyst as seen lipomatous elements creates on CT scan problems in differentiating these benign tumors from renal carcinomas. Surgical exploration to establish the diagnosis may be necessary. Multiple angiomyolipomas as well as renal cell carcinomas are associated with tuberous sclerosis. Urologic management. Renal neoplasm. Symptoms of hematuria, flank pain or an abdominal mass usually initiate urologic evaluation. However, with the widespread use of diagnostic ultrasound and CAT scanning, many renal masses are discovered incidentally. Correct management of the renal mass depends upon establishment of the correct diagnosis. Fortunately, a number of radiograph studies are available to help the urologist in making an accurate diagnosis. The intravenous pyelogram is useful as an radiographic examination although used much less frequently since CT scanning gives some much information. The IVP yields information regarding the size and shape of the kidneys, the presence of obstruction or distortion of the collecting system as well as information about the soft and bony tissues of the retroperitoneum and pelvis. If a renal mass is noted on the IVP, its nature, cystic or solid, must then be determined. Renal ultrasound is an excellent modality for determination of the nature of the mass. Renal cyst are characterized ultrasonographically by Right Renal Carcinoma their smooth walls, absence of internal echoes and build up of echoes behind their posterior walls. Solid masses lack these characteristics. If a mass has all the criteria of a simple cyst the evaluation can end. However, if there is question or if the mass is not cystic in nature, CT scanning should be obtained. The CT
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scan is usually able to differentiate between solid and cystic masses. Benign cystic masses are filled with fluid having a x-ray density (Hounsfield units) of water and exceedingly thin and smooth walls. Solid masses lack these characteristics. Very occasionally CT scanning will be unable to fully characterize the renal mass. If none of the above is successful in determining the nature of the mass, open surgical exploration may need to be performed. Transitional cell carcinomas (TCC)of the kidney, those arising from the urothelial lining of the renal calyces or pelvis, range in their appearance on IVP from a small "filling defect" to a large mass resulting in nonvisualization of the affected renal unit. A radiographic filling defect in the renal pelvis may represent a radiolucent calculus (uric acid) or a transitional cell carcinoma. If the diagnosis is uncertain, a CT scan can be helpful since CT will usually detect small amounts of calcium present in a uric acid calculus but absent in a neoplasm. Retrograde pyelography may also be helpful especially when obstruction by the lesion leads to nonvisualization on IVP of the affected renal unit. Once a diagnosis is established, treatment can be initiated. Simple renal cysts need no treatment. Radical nephrectomy, removal of the affected renal unit with its surrounding Gerota's fascia has been the treatment of choice for localized renal cell carcinoma of the kidney. However, in the last decade the use of partial nephrectomy has been more widely employed especially in cases where the tumor is peripheral and less than 4 centimeters in diameter. In cases in which removal of a kidney would lead to significant loss of renal function, as in the patient with a solitary kidney, partial nephrectomy is the standard therapy. Extension of a renal cell tumor thrombus into the renal vein, vena cava or even right atrium is not a contraindication for surgical treatment. The management of patients with proven distant metastases is controversial but in some situations is justified if adjuvant therapy is planned. Transitional cell carcinoma of the kidney is approached somewhat differently from renal cell carcinoma. Treatment entails nephroureterectomy, removal of the kidney with Gerota's fascia in continuity with the entire ureter and a cuff of bladder. Failure to remove the distal ureter during the operation canl result in a "recurrence" of transitional cell carcinoma within the remnant ureter. Transitional Cell of Renal In the months and years following Pelvis nephroureterectomy, Patients with TCC
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of the kidney must be followed closely with frequent cystoscopies since they are at high risk for developing transitional cell carcinomas within the urinary bladder. URETER Clinical Anatomy. The ureter, which lies entirely in the retroperitoneal space, serves as a conduit for the passage of urine between the kidney and bladder. A muscular tube, the ureter's peristaltic activity literally pushes urine toward the bladder. Normally, the ureter is less than one centimeter in diameter. Natural sites of ureteral narrowing occur at the junction between the renal pelvis and the beginning of the ureter, i.e., the ureteropelvic junction, (UPJ), the pelvic brim where the ureter must cross the iliac vessels and at the hiatus through which the ureter enters the urinary bladder. These sites are of clinical importance since they are frequently the points at which renal stones will lodge as they pass from the kidney. Clinical Pathology. Stones and neoplasms are the two most commonly encountered clinical problems involving the ureter. Ureteral stones usually originate in the kidney. Their composition is the same as those described under renal lithiasis, that is, calcium oxalate or phosphate, uric acid, cystine and infection stones of magnesium ammonium phosphate.
Stone impacted at ureteral orifice
Urologic Management. Stones. Patients with ureteral calculi usually present with the acute onset of pain resulting from obstruction. The pain distribution will vary with calculus location, upper ureteral stones causing pain which radiates from the flank to the upper abdominal wall, while distal stones cause pain which radiates to the lower abdomen,
Purulent drainage exuding around a ureteralcatheter placed cystoscopically above obstructing ureteral calculus in the lower ureter.
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groin, testicle or labia. The small diameter of the ureter impedes the passage of calculi. In the absence of high grade obstruction or infection, stones smaller than 5mm have a greater than 50% chance of passing into the bladder without manipulation and thus may be managed expectantly. However, as stones size increases, the probability of spontaneous passage greatly diminishes. In addition to size, the treatment of ureteral stones depends on composition and position as well as the presence or absence of infection. Ureteral obstruction complicated by infection is a urologic emergency with emergent treatment directed toward reestablishment of adequate urinary drainage. Usually this can be accomplished by cystoscopic placement of a ureteral stent or if a stent cannot be passed around the stone, percutaneous nephrostomy can achieve the desired drainage. The majority of stones do not require emergent management. Uric acid stones in the ureter, as those of the kidney, may be treated successfully by urinary alkalinization. This is not always successful and thus these and calcium containing stones in the upper or midureter may be treated either via a percutaneous nephrostomy followed by extraction/intraluminal lithotripsy or with extracorporeal shock wave lithotripsy (ESWL). There are a number of endoscopic alternatives for the treatment of stones of the lower ureter. Perhaps one of the most widely employed techniques is basketing. A basket is passed endoscopically into the ureter and past the offending stone. Opening the basket then creates a space for stone entrapment and removal. Basketing is usually limited to stones 0.5cm in diameter. Although stone basketing can be performed under fluoroscopy this is a "blind" procedure in that once the basket enters the ureteral orifice it is no longer directly visible. Modern ureteroscopes permit direct visualization of ureteral calculi. Rigid ureteroscopes are especially useful in the portion of the ureter found below the pelvic vessels. Through their working channels, baskets, laser fibers and ultrasonic or electrohydraulic probes can be passed for stone entrapment or fragmentation. The Holmium YAG laser is the most commonly employed instrument for intraluminal stone fragmentation. Modern flexible ureteroscopes permit access to the upper ureter and into the kidney so that intracorporeal fragmentation can be done throughout the collecting system.
Ureteral stone as viewed through a 7.2 French rigid ureteroscope.
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As with stones of the kidney, ureteral stones, once removed are sent for chemical analysis. Medical management, the basis of which is increased daily hydration, is then instituted in order to prevent stone recurrence.
Clinical Pathology. Ureteral Neoplasms. The majority of ureteral neoplasms are carcinomas arising in the uroepithelium. These transitional cell carcinomas (TCC’s) vary in grade from well to poorly differentiated. Staging of ureteral tumors is based upon the depth of invasion through the ureteral wall. Rarely, benign fibromuscular polyps of Ureteral Neoplasm the ureter are encountered causing Note irregular intermittent obstruction, pain and appearance of distal hematuria. ureter. Pathologic processes outside the ureter can lead to ureteral obstruction. For example, metastatic malignancies from other primary sites, especially those arising in the pelvis, can encase the ureter leading to hydronephrosis and eventually renal nonfunction. Retroperitoneal fibrosis, a benign extraureteral proliferative fibrotic process may be idiopathic or result from methylsergide ingestion can lead to bilateral ureteral obstruction and acute renal failure. Urologic Management. Ureteral Neoplasms and Retroperitoneal fibrosis. The approach to transitional cell carcinoma of the ureter is similar to that of the kidney, that is, nephroureterectomy. Occasionally, less extensive surgery may be undertaken, especially for a low grade carcinoma involving the distal ureter. This situation is ideally suited for distal (partial) ureterectomy and reimplantation of the remaining ureter into the bladder. For tumors of the upper ureter, such an approach is technically much more difficult since a tension free uretero-ureterostomy is usually not attainable. Close followup of these patients is important for they are at high risk for the development of subsequent tumors in the urinary bladder and remaining ureteral segment. Fibromuscular polyps can be managed by simple local excision. Management of extrinsic obstruction of the ureter will depend upon the etiology.
Retroperitoneal Fibrosis Note fibrosis tissue surrounding aorta and vena cava
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Retroperitoneal fibrosis, mentioned above, is treated operatively by freeing the ureters from surrounding fibrotic process, a procedure called ureterolysis, and then fixing the ureters into a position which will avoid future entrapment.
Urinary Bladder Clinical Anatomy. The urinary bladder is a hollow extraperitoneal muscular organ located deep in the pelvis. The bladder mucosa a smooth lining of uroepithelial cells (transitional cells), lies atop the detrusor muscle which funnels into the bladder neck and urethra. The bladder neck receives muscle fibers from the distal ureters, the combination of which forms the area called the trigone. Below and in continuity with the trigone, the circularly oriented fibers of the bladder neck form the functional internal sphincter. Storage and timely evacuation of urine requires complex coordination between the muscles of the body of the bladder and those of the bladder neck and urethra. The body of the bladder is principally enervated by the parasympathetic nervous system while the bladder neck and associate urethral musculature are controlled by the sympathetic nervous system. Somatic (voluntary) control of micturition is coordinated in the sacral (S2,3,4) portion of the spinal column where neurons forming the pudendal nerve are located. The pudendal nerve controls the "external sphincter" (a specialized condensation of fibers of the levator ani) surrounding the urethra, relaxation of which occurs with the initiation of a detrusor contraction. Clinical Pathology. Cystitis.
Infections of the bladder may be simple or complicated. Simple infections are not associated with other genitourinary pathology such as obstruction or the presence of a foreign body whereas complicated infections imply additional pathology. Simple urinary tract infections, UTI's, are extremely common. Gender predilection for bacterial infections varies with age: bacterial infections are more common in newborn boys while prepubescent and young adult women have far more simple bladder infections than males in the corresponding age group. With late middle age and among the elderly, infections occur without gender preference. Gram negative bacteria, especially E.coli, cause the majority of simple
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infections. Cystitis is usually heralded by urinary frequency and urgency. Urgency may be so severe as to result in incontinence. Simple infections may result in punctate disruption of the bladder mucosa causing bleeding, so-called hemorrhagic cystitis. Nonbacterial infections are principally fungal, tending to occur in patients who have had an indwelling catheters/stents and are concomitantly treated over prolonged periods with broad spectrum antibiotics. Immunosuppression as well as debilitating disease predispose to fungal cystitis especially in the hospital setting. Urologic Management. Cystitis. Symptomatic uncomplicated bacterial infections of the urinary bladder are managed by the administration of oral antibiotics. Length of treatment varies depending upon the clinical situation but generally 7-10 days of treatment is the maximum. In adult women in whom recurrent uncomplicated infections occur frequently, 3 days of oral antibiotic therapy at the first signs of infection may be adequate and avoids a more prolonged course of antibiotics with its attendant complications. Simple cystitis is unusual in a young male so that an associated anatomical abnormality needs to be ruled out. Infections of the bladder in the older male occur with increasing frequency paralleling the increase in pathology of the prostate (BPH, prostatitis). A number of antibiotics are suitable for treatment of bacterial cystitis and include the sulfas, quinolones and furadantoins. Fungal infections generally occur in the more complicated clinical settings. Discontinuation of broad spectrum antibiotics and removal of indwelling catheters or stents, if feasible, may correct the problem. If these measures prove insufficient, antifungal agents may need to be administered. Clinical Pathology. Bladder stones. Bladder stones are principally encountered in patients with bladder outlet obstruction. In the male patient outlet obstruction usually is secondary to prostatic enlargement. An intravesical foreign body such as a retained suture from pelvic surgery can also serve as a nidus for bladder stone formation. Open surgical removal or intravesical lithotripsy as well as correction of the underlying urologic pathology (BPH, foreign
Large bladder calculus
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Bladder stone fragmented with electrohydraulic lithotripsy
body removal) is the goal of urologic management. Clinical Pathology. Bladder Carcinoma. Transitional cell carcinomas (TCC) arising from the bladder's epithelium account for the majority of bladder cancers. Adenocarcinomas and squamous cell carcinomas of the urothelium are also seen but with much less frequency than transitional cell carcinomas. Sarcomas originating in the bladder's connective tissue and muscle do occur but are rare. There are three broad clinicopathologic forms of transitional cell carcinomas: carcinoma in situ (CIS), papillary and nodular/invasive. Patients may present with a single or with a combination of clinicopathologic forms. Carcinoma in situ is an intraepithelial neoplasm which may not be visible on routine cystoscopy. Papillary tumors are exophytic, growing into the lumen of the bladder on a fibrovascular stalk varying in size from that of a match head to a billiard ball. Flat Staging, Bladder Cancer invasive carcinomas tend to be erosive and invade the underlying Tis-In situ muscularis layer. Multifocality Ta-Mucosa and recurrence over time are T1-Lamina propria characteristic of transitional T2-Superficial Muscle cell carcinomas. In general, T3a-Deep Muscle recurrences are of similar grade T3b-Deep &Serosa and stage as presenting tumors but this is variable. Grade (I-III) and stage (A,B1,B2,C & D or TNM)) are important determinants of prognosis. Grade is a function of cell morphology while stage is determined by depth of muscle invasion. Urologic management. Bladder cancer. Treatment of bladder cancer depends upon tumor stage and grade as well as upon the overall medical condition of the patient. Diagnosis is made by endoscopic biopsy accompanied by a bimanual examination under anesthesia. Low grade superficial tumors can usually be managed with organ preserving endoscopic techniques of electrofulguration or Superficial papillary carcinoma of electroresection. The propensity for the bladder these tumors to recur at other sites within the urinary bladder over time has led to "observation cytoscopy" as part of patient management strategy. This entails the timely performance of interval cystoscopies,
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inspecting the bladder mucosa for evidence of renewed tumor growth. Following removal of a Intravesical Agents superficial bladder tumor of low grade, observation cystoscopies are performed Mitomycin C every 3 months for 2 years, then every 6 Adriamycin months for the next 2 years and finally BCG yearly until (if and when) new tumor growth occurs. If low grade tumors recur frequently, intravesical chemotherapy/immmunotherapy with agents such as mitomycin-C/BCG are instilled directly into the bladder. In general, high grade invasive nodular tumors are not amenable to endoscopic techniques since the margins of tumor growth are usually not discernable. Most high grade invasive cancer, then, are managed with total removal of the bladder (radical cystoprostatectomy) accompanied by some form of urinary diversion. Urinary diversion may consist of a noncontinent bowel segment connected to the ureters and directed into a collection device on the skin or a continent pouch with a cutaneous stoma in which urine removal is not continuous but depends on timely self-catheterization through a cutaneous stoma. An alternative to these is the surgical creation of an orthotopic bladder replacement fashioned from small or large bowel segments connected directly to the urethra. Occasionally, high grade lesions are located in a position within the urinary bladder that is amenable to partial removal of the bladder, i.e., partial cystectomy rather than radical cystectomy. This operation has the advantage of not requiring urinary diversion. The treatment of carcinoma in situ (CIS) can be particularly vexing for both patient and physician. In general, CIS occurs in combination with either papillary or nodular invasive disease. Occasionally it occurs as an isolated entity. CIS may have an indolent course but also may be a harbinger of invasive disease. Treatment is aimed at the entire mucosa and involves the intravesical administration of antineoplastic agents among which are mitomycin C and BacillusSolid high grade invasive bladder tumor Calmette-Guerin (BCG). If these agents fail to obliterate the disease, radical cystectomy is usually performed. Although there has been some success with combination chemotherapy for non-organ confined disease, once bladder cancer metastasizes prognosis is poor.
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Clinical Pathology. Neurogenic Bladder/Urinary incontinence. The urinary bladder is an organ for the storage and expulsion of urine. Its neuromuscular control is complex in that it involves both the autonomic and somatic nervous systems and is under both voluntary and involuntary control. Additionally, bladder contraction and relaxation must be coordinated with periurethral muscular activity for physiologic micturition and urinary storage. Although a simplification, it is helpful to think of the neural control of the bladder as a balance between the parasympathetic (arising from S2, S3 and S4) and sympathetic nervous systems (arising from L1, L2 and L3). The parasympathetic system enervates the body of the detrusor and is responsible for bladder contraction while the sympathetic system is present mainly at the bladder neck and proximal urethra and is responsible for maintaining tone of these area during bladder filling and their relaxation during voiding. Higher centers (cerebral) are mainly involved in voluntary bladder control. The so-called neurogenic bladder develops from neurologic disturbances in these control systems resulting in clinical disorders of bladder filling or emptying. A number of classification systems for the neurogenic bladder have been developed to aid the clinician in patient diagnosis and management. The Lapides classification is widely used in urologic circles and separates neurogenic bladder dysfunction into 5 categories: uninhibited, reflex, sensory, motor and autonomous. The cystometrogram, a passive bladder filling study measuring bladder pressure as a function of volume, in combination with the clinical findings is usually sufficient to categorize the type of neurogenic bladder dysfunction within the Lapides system. The uninhibited neurogenic bladder is associated with loss of higher motor regulation (inhibition) of the sacral voiding center. Patients complain of frequency, urgency and incontinence. The cystometrogram shows "hyperreflexia" at low volumes. Brain and spinal cord tumors and cerebral vascular accidents are commonly associated with this type of neurogenic bladder. A reflex neurogenic bladder is associated with complete transection of the spinal column. These patients are unable to initiate a voluntary bladder contraction and have no sensation of bladder filling. Incontinence occurs because of pure reflex bladder contraction. A sensory neurogenic bladder develops when the afferent pathways from the bladder are disrupted. Peripheral neuropathies such as seen with diabetes are responsible for this problem. Lack of awareness of bladder distention eventually leads to hypotonicity of the detrusor muscle. A motor neurogenic bladder also develops when the peripheral motor units to the bladder are destroyed such as may occur
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after extensive pelvic surgery. These patients are aware of bladder filling but are unable to initiate a bladder contraction. If both sensory and motor units to the bladder are destroyed, an autonomous neurogenic bladder results. Neurologic bladder dysfunction is not the only cause of urinary incontinence. Overflow incontinence can result from bladder neck obstruction such as occurs with longstanding benign prostatic hyperplasia while urge incontinence may be occur during a severe bladder infection. Urgency, frequency and urge incontinence not associated with infection, overflow or neurologic problems may Neurogenic Bladder be the result of the "unstable Lapides System bladder". Diagnosis of the unstable bladder is confirmed by cystometry Uninhibited which shows bladder contraction at Reflex low volumes associated with Sensory activities such as coughing or Motor movement (as opposed to stress Autonomous incontinence which shows no bladder contraction with these activities). Stress incontinence is a particularly troublesome problem for patients of whom the majority are women. Loss of anatomic muscular support of the bladder base as well as the proximal urethra leads to the involuntary loss of urine with increases in intraabdominal pressure. Finally, incontinence may also result from pathologic processes which lead to fistulization between the bladder and the vagina (vesicovaginal fistula) or occasionally between the ureter and vagina (ureterovaginal fistula). Urologic Management. Neurogenic bladder/incontinence. Treatment goals for the patient with a neurogenic bladder are preservation of the upper tracts (kidney and ureters), prevention of infection and attainment of a balance between the storage and emptying capacity of the bladder. Individualization of treatment depends on the extent of the neurologic deficit (e.g. paraplegia vs. quadriplegia), patient ability to comprehend and cooperate and the presence of willing caregivers. Pharmacologic agents which suppress detrusor contractions (anticholinergics) can be used successfully in patients with diminished ability to store urine. Transurethral intermittent clean catheterization is widely used in patients with problems in bladder emptying. This technique involves the timely (every 4-6h) catheterization and emptying of the bladder by the patient or caregiver using a clean (not sterile) catheter. In some situations a combination of these treatments in addition to surgery can create socially and medically acceptable situation for the patient. For example, in children with myelodysplasia, a suitable organ for bladder storage is created by augmenting the bladder with a segment of bowel and lengthening the urethra (creating continence)
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by tubularizing the bladder neck. Bladder emptying then is accomplished through intermittent catheterization. Stress urinary incontinence in women can usually be diagnosed by history and physical examination. The Bonney test, an office examination performed with the patient in the supine position is usually diagnostic. The bladder is filled (200cc) and the patient is asked to cough. If leakage of urine occurs and is corrected by gentle transvaginal elevation of the paraurethral tissues the diagnosis is almost assured. Treatment depends of the severity of symptoms. Exercises to strengthen the pelvic floor (Kegel exercises) can be helpful. If symptoms are severe surgical correction may be necessary. Surgical goals are aimed at support to the urethra and bladder neck area. This can be accomplished either transabdominally or transvaginally.In the last decade the use of transvaginal slings have gained popularity for the treatment of stress incontinence. The unstable bladder is usually treated with anticholinergic agents while fistula, vesicovaginal or ureterovaginal, require surgical correction. Clinical Pathology. Interstitial Cystitis. Interstitial cystitis is a poorly understood chronic process occurring in both sexes but much more commonly in females. The clinicopathologic presentation is one of increasing urgency and frequency associated with suprapubic discomfort. The histopathology is not well characterized but is usually associated with submucosal mast cell infiltration and a transmural fibrosis. Occasionally an ulcerative mucosal process is found endoscopically, the so-called Hunner's ulcer. Symptoms may become so severe as to be totally disruptive of the patient's daily activities. Urologic Management. Interstitial Cystitis. Treatment of interstitial cystitis is controversial. Hydrodistention (distention of the bladder while the patient is under anesthesia) is successful in Interstitial cystitis some patients. The intravesical Pain instillation of DMSO is widely used. Frequency Adjuvant treatments include the use of Hunner’s Ulcer antispasmodic and antidepressive medications. In severe cases either augmentation of the bladder or urinary diversion may be required.
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URETHRA Clinical Anatomy. The urethra is a tubular structure serving as a conduit for urine in both sexes. Additionally, in the male it is a conduit for the egress of semen. The proximal urethra is covered with transitional cells which are replaced progressively distally by pseudostratified columnar and then stratified squamous epithelium. The urethra of the female is supported and fixed laterally by the urethral pelvic ligaments and anteriorly by the urethral pubic ligaments. The male urethra is divided into segments: prostatic, membranous, bulbous and pendulous. Distally the pendulous urethra widens into the fossa navicularis. The puboprostatic ligaments fix the prostate and prostatic urethra while the thick musculature of the urogenital diaphragm immobilizes the membranous urethra. Clinical Pathology. Urethral Infection. Infections of the urethra are usually venereal in origin. A thick purulent discharge with associated dysuria is characteristic of a gonorrheal infection. Non-gonococcal urethritis caused by chlamydia or ureaplasma usually produce only a scant discharge typically detected in the morning upon waking. A urethral diverticulum can be the source of a nonvenereal urethra infection and give rise to symptoms of dysuria, postmicturition dribbling and in the female, dyspareunia. Diverticula may be either congenital or acquired. Urologic Management. Urethral Infection. The treatment of urethritis is based on the identification of the infecting organism. Recommendations for the treatment of venereal infections change periodically and are available through the Center for Disease Control in Atlanta. Currently, Ceftriaxone, I.M. or oral Norfloxacin are effective agents in the treatment of gonorrhea. The treatment for nongonococcal urethritis is oral tetracycline. Should a urethral diverticulum be the source of urethritis, treatment is directed toward its surgical removal. Clinical Pathology. Urethral Carcinoma. Carcinomas of the urethra are uncommon but not rare. Hematuria, dysuria or a pelvic or perineal mass may be the presenting symptoms/findings.
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Urologic Management. Urethral Carcinoma. Treatment of carcinoma of the urethra depends on location and size. Superficial carcinoma of the proximal urethra occurring subsequent to Urethral Cancer removal of superficial bladder tumors can be treated with transurethral resection or 1.Local excision fulguration. Small distal tumors of the female urethra can be treated with local excision. 2.Exenteration Bulbar urethral carcinomas in the male usually require cystectomy and urethrectomy for 3. Radiation Rx adequate treatment. Proximal urethral carcinomas in the female are treated with either cystectomy and urethrectomy or interstitial radiotherapy.
Clinical Pathology. Urethral Stricture. Urethral strictures are most commonly encountered in the adult male population. In the early part of the twentieth century, strictures were the result of untreated venereal disease, especially gonococcal infections. Currently, trauma both civilian and iatrogenic accounts for most of the urethral stricture disease. Crush injuries to the pelvis can result in total disruption of the membranous urethra. Subsequent healing leaves a fibrotic gap Bulbous urethra stricture debetween distal prostatic urethra and monstrated by retrograde ureththe undamaged bulbous urethra. rogram Strictures of the bulbous urethra may result from straddle injuries to the perineum, instrumentation or untreated venereal infection. Indwelling Foley catheters can cause strictures anywhere along the pendulous urethra as well as at the urethral meatus. Urologic Management. Urethral Stricture. Treatment of urethral stricture depends upon location, length and etiology. Short strictures of the bulbous or pendulous urethra can be treated with periodic dilatations using woven bougies (filiform and followers). This method usually affords only temporary relief of symptoms and must be repeated every 4-6 weeks. Incision, using either a endoscopic knife or a
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Urethral stricture as viewed through an endoscope
laser, may be curative. Surgical repair consisting of excision and end to end anastomosis or incision and tissue transfer techniques will usually correct the problem. Post traumatic strictures of the membranous urethra resulting from crush injuries to the pelvis may require removal of the pubic symphysis and rerouting of the anterior urethra past the obstruction for correction. PROSTATE Clinical Anatomy. The prostate is a secondary sex organ located deep within the male pelvis. It is intimately connected with the bladder, seminal vesicles, and urethra and separated by a thin fascia (Denonvillier's) from the anterior wall of the rectum. Although clinical and endoscopic reference is made to the lobes of the prostate, there are no true anatomic lobes. Rather, it is more nearly correct to describe the prostate by zones, peripheral, central, anterior and transition. The prostatic portion of the urethra runs centrally through the gland. Multiple prostatic ducts draining the glandular epithelium empty into this portion of the urethra providing the prostatic contribution to seminal fluid. In the distal prostatic urethra lies the prostatic utricle, a Mullerian duct analog of the uterus. The utricle appears as a small pit within the verumontanum (“veru”) (Latin, for mountain ridge) which is an endoscopic landmark for the distal portion of the prostatic urethra. The ejaculatory ducts, the conjoined conduits of egress for the vas deferens and the seminal vesicles, lie immediately adjacent to the verumontanum and their urethral openings can be seen endoscopically as two small pits adjacent to the verumontanum. The prostate is fixed in the pelvis by the bladder neck, investing endopelvic fascia and two thick condensations of fascia attached to the periosteum of the pubis, the puboprostatic ligaments. Inferiorly, the apex of the prostate rests upon the Urogential (U.G.) diaphragm through which the membranous urethra passes.
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Prostate specific antigen PSA and Age (PSA), a serine protease is found only in prostate epithelial cells ng/mL and in the seminal fluid where it is Yr. 40-49 0.0-2.5 responsible for the seminal liquification after ejaculation. 0.0-3.5 PSA has become a tumor marker for 50-59 prostate cancer as well as a tool 0.0-4.5 for prostate cancer screening. 60-69 Nomograms are available for normal 0.0-6.5 serum levels of this enzyme as a 70-79 function of age. Serum elevations of PSA after local therapy (radical prostatectomy, radiation therapy) for the treatment of cancer usually precede the develop of clinical recurrence. Elevations above the norm in the patient without prostate cancer can occur as a result of BPH, infection or trauma.
Clinical Pathology. Prostatic Infections\Inflammation. Bacterial prostatitis may be either acute or chronic. Patients with acute bacterial prostatitis are usually toxic with severe perineal pain, dysuria and fever while the hallmark of chronic bacterial prostatitis is recurrent urinary tract infections. In Prostatitis patients with chronic bacterial prostatitis, localization of Acute Bacterial infection to the prostate is Chronic Bacterial essential for diagnosis and Abacterial treatment. Localization is usually Prostadynia done by the so-called three glass urine test in conjunction with examination of expressed prostatic secretions. The patient is asked to void into three separate specimen containers, the first representing urine from the urethra, the second from the bladder. Transrectal "massage" of the prostate is then performed by the physician. Prostatic fluid expressed into the urethra is collected and the patient is then instructed to void into a third container. The expressed prostatic secretions are examined microscopically while the collected urines are cultured separately. A log difference in bacterial count between the post-massage and first two urines localizes the infection to the prostate.
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Nonbacterial prostatitis is a poorly understood entity characterized clinically by episodes of dysuria, frequency and perineal discomfort but not infection. The expressed prostatic secretions, in this clinical entity, contain more than 10-15 WBC's per high powered field. Prostadynia, or the painful prostate syndrome, is associated with neither infection nor excessive white cells in the prostatic NIH classification of prostatitis fluid. Recently, Category I. Acute bacterial prostatitis Acute infection of the prostate the NIH has Category II. Chronic bacterial prostatitis Recurrent infection of the prostate developed a new Category III. Chronic abacterial prostatitis No demonstrable infection classification (CPPS) system for Category IIIa. Inflammatory CPPS White cells in semen/EPS/VB3 prostatitis.
Category IIIb. Noninflammatory CPPS No white cells in semen/EPS/VB3 Category IV. Asymptomatic inflammatory No subjective symptoms. Found prostatitis incidentally CPPS=chronic pelvic pain syndrome EPS=Expressed prostatic secretions VB=Voided urine post prostatic massage
Urologic Management. Prostatic Infection/Inflammation. In cases of fulminant acute bacterial prostatitis (high fever, perineal pain, difficulty voiding) hospitalization and intravenous antibiotics covering gram negative organisms is prudent. Patients with chronic bacterial prostatitis are treated with oral antibiotics based upon urine culture results. Those with nonbacterial prostatitis may be treated empirically with antibiotics but prolonged and repeated courses are unwarranted. Reassurance and local measures such as sitz baths are helpful in this group of patients as well as those with prostadynia. Clinical Pathology. Benign prostatic hyperplasia (BPH). Benign prostatic hyperplasia (BPH) is very common. After the age of 40, there is a gradual enlargement of the glandular and stromal tissue of the transition zone of the prostate. This can lead to the clinical syndrome of “prostatism”, i.e., urinary frequency, urgency, decrease in the caliber of the urinary stream and nocturia. The underlying pathophysiology is not understood. The enlarging transition zone compresses the more peripheral prostatic tissue, the latter often referred to as the surgical "capsule" of the prostate. This peripheral tissue is rich in muscle fibers enervated by the sympathetic (alphaadrenergic) system. It is the combination of the physical enlargement of the prostate in combination with the adrenergic input from the compressed surgical capsule that contributes to the development of the spectrum of clinical
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problems included prostatism.
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Urologic Management. Benign Prostatic Hyperplasia. Treatment of benign prostatic hyperplasia is based on severity of symptoms which can be quantitated via Veru scoring systems such as the International Prostate Symptom Score System based upon feelings of urgency, incomplete emptying, frequency, strength of stream and nocturia. For Endoscopic view of many patients, symptoms wax and wane enlarged prostatic over the years with relatively long tissue periods of stabilization. When treatment is warranted, it may take the form of surgical or medical intervention. Transurethral resection of the prostate (TURP), an endoscopic surgical procedure widely practiced throughout the world, is considered the "gold standard" for surgical techniques. Occasionally, large adenomas (>60 grams) cannot be removed transurethrally and must be approached through open surgery-simple suprapubic or retropubic prostatectomy. The goal of both endoscopic and open surgery is to remove adenomatous hyperplastic (transition zone) tissue surrounding the urethra. Surgically removed tissue is collected and examined histologically. The surgical bed then reepithelializes with transitional epithelium. Alternatives to these traditional approaches include thermal ablation of obstructing tissue with a laser (KTP or Holmium YAG) or BPH Medical Rx radiofrequency heating of the periurethral prostatic tissue. Finasteride Nonsurgical approaches are relatively -Blockers new in the treatment of BPH. Finasteride or Dutasturide, inhibitors of the conversion of testosterone to dihydrotestosterone, a hormone necessary for sustenance of the glandular elements of the prostate, has been shown to decrease the volume of the prostate and lessen the severity of symptoms. Oral alpha adrenergic blockers (tamsulasin) work by a different mechanism in relieving outlet obstruction and improving voiding by relaxing the sympathetic fibers of the bladder neck and periprostatic tissue. Clinical Pathology. Prostatic Adenocarcinoma. Adenocarcinoma of the prostate is the most common neoplasm found in the adult male. It is a cancer with a wide spectrum of biologic behavior from indolent to aggressive. Approximately
TNM Staging System Prostate Cancer
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T1-Clinically unapparent T1a<5% at TURP T1b>5%at TURP T1c-Biopsy driven by PSA T2-Tumor confined in prostate T2a-Half lobe or less T2b-More than half lobe T2c-Both lobes T3-Through capsule/involves seminal vesicle T4-Fixed tumor invading adjacent structures
85% of these cancers arise in the peripheral zone of the prostate, the remainder in the transition zone. Grading of prostate cancer, using the widely employed Gleason System, is not determined by individual cell morphology but rather by patterns of gland formation. Grading has been found to be one of the most powerful predictors of tumor aggressiveness and is based upon histopathologic scores determined by major and minor patterns of gland formation which range from 1-5. By adding the major pattern of carcinomatous glands to the minor pattern a pathologic score is determined: 2corresponds to "well-differentiated" carcinomas, 5-7 to "moderately differentiated" and 8-10 to "poorly differentiated" carcinomas. Clinical staging is also of importance in determining management. The TNM system for clinical staging is given in the accompanying box. The TNM system has gained acceptance especially since it allows for staging of those patients found to have carcinoma as a result of PSA (prostatic specific antigen) elevation and not palpable disease.
Urologic Management. Carcinoma of the Prostate. Since there is a spectrum of treatment options available for the management of carcinoma of the prostate, treatment must be tailored for each patient with consideration given to age, comorbid conditions, grade and stage of the tumor. Treatment options include "watchful
waiting", radiation therapy, radical prostatectomy, cryosurgery and hormonal ablation.
Watchful waiting is usually reserved for older patients (70-75 years) with small low grade neoplasms. Periodic office visits and examinations monitor the patient for the development of local symptoms (bladder outlet obstruction) or distant disease. Current controversy revolves about the appropriateness of this option in younger patients (65-70 years). Radical surgery, removal of the entire prostate and seminal vesicles, has been performed for almost 100 years. Currently, the surgery is performed most often through a retropubic approach although laparoscopic techniques using robotic technology greatly reduces the length of hospitalization and leads to more rapid recovery. For organ confined disease, T1 or T2, either open or laparoscopic approaches offer an excellent chance for cure. Radiation therapy, an alternative to surgery, can be delivered either via external beam radiotherapy or through the placement of radioactive “seeds” (I125) within the prostate itself. Whether radiotherapy is equally efficacious stage for stage with radical surgery is widely debated. Complications of radiation therapy include diarrhea,
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cystitis, impotence and incontinence. However, impotence and incontinence are less frequently encountered after radiation therapy than after surgery. Cryosurgical ablation is another approach to the treatment of organ confined prostate cancer. Treatment consists of the placing stainless steel probes (3mm) percutaneously into the substance of the prostate under ultrasound guidance. Through the probes, liquid nitrogen or argon gas is circulated. This creates an expanding "iceball" throughout the prostate the limits of which can be controlled by watching a freeze "front" progress within the tissue under transrectal ultrasound observation. The cycle of freezing and thawing of the prostate tissue results in coagulation necrosis of the tissue. As with other forms of therapy, patients treated with cryosurgery are at risk of developing impotence and incontinence after treatment. However, the procedure is minimally invasive and early results have been encouraging. The discovery that prostate cancer regresses after depletion of circulating, testosterone led to the awarding of the Nobel Prize in medicine in 1941. Although there can be rapid clinical regression and relief of symptoms of prostate cancer after testosterone withdrawal, hormonal ablation is not curative. Consequently, hormone ablation is usually reserved for patients with symptomatic metastases. Hormone ablation can be accomplished via bilateral orchiectomy, administration of luteinizing hormone releasing factor agonists (Lupron™).
PENIS Clinical Anatomy. The penis is the male organ for copulation as well as for waste elimination. The erectile bodies of the penis, the two corpora cavernosa and the corpus spongiosum are responsible for the rigidity needed for intromission. In the perineum, the corpora cavernosa are fixed to the ischial rami and covered by the ischial cavernosal muscles while the bulbospongiosus muscle covers the corporus spongiosum which in turn surrounds the bulbous urethra. The corpus spongiosum widens distally to form the body of the glans penis. The arterial supply to the penis is derived from the pudendal artery, a branch of the internal iliac artery. Within the erectile tissue are vascular lacunae which fill during sexual arousal providing turgidity. During an erection, emissary veins draining these lacunae contract and are compressed until detumescence. Nervous system control of erection is through the parasympathetic system.
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Clinical Pathology. Penile Infection/Inflammation. The skin of the penis is susceptible to infectious and inflammatory changes. Lack of cleaning of the prepuce can lead to balanitis a problem common in diabetics who are, in general, more susceptible to infections. Repeated infections of the foreskin can lead to phimosis, a cicatrization of the foreskin, which leads to further infections as retraction of the foreskin becomes more painful and difficult. A related iatrogenic problem occurs when the foreskin is retracted for inspection or urethral catheter placement and not replaced back over the penile corona. The foreskin becomes edematous, leading to a condition called paraphimosis which may be difficult to correct without the aid of local anesthesia. Venereally contracted viral infections caused by the herpes simplex virus are characterized by painful periodically appearing cutaneous vesicles. Condyloma acuminata transmitted by the papilloma virus lead to warty cutaneous growths which can reach considerable size if not treated. Peyronie's disease is a poorly understood inflammatory disease of the tunica albuginea in which a firm plaque develops leading to loss of elasticity. The plaque causes a curvature of the penis during erection with resulting pain during intercourse. Urologic management. Penile Inflammation/Infection. Balanitis can usually be prevented by attention to local hygiene. Should a Candida species be the offending organism, topical antifungal agents are used. When infections are recurrent or associated with phimosis, circumcision will resolve the problem. Viral infections of the penile and perineal skin are troublesome problems. Herpes simplex infections are treated with both topical and oral acyclovir. Sexual activity must be limited when vesicular eruptions are evident. Small condyloma acuminata (venereal warts) can be managed with topical keratolytic agents such as podophyllin. Large lesions or very extensive lesions may require more extensive procedures for removal via electrofulguration or laser surgery. Treatment of the sexual partner is an important consideration for both of these clinical problems. Peyronie's disease when mild, that is associated with minimal curvature and discomfort during erection is managed conservatively. Should curvature and pain be severe, excision of the plaque tissue grafting may be needed.
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Clinical Pathology. Priapism. Prolonged erection without sexual stimulation is priapism. Only the corpora cavernosa become erect. At times the etiology is unclear but patients with sickle cell anemia or leukemia are at risk for developing this painful condition. If treatment is unsuccessful, the corpora become fibrotic and impotency ensues. Urologic Management. Priapism. The treatment of priapism is directed at correcting the underlying pathology. For patients with sickle cell anemia, transfusion, nasal oxygen and systemic alkalinization may lead to detumescence. Cases caused by the intracorporeal injection of vasodilatory agents can be managed by direct injection of epinephrine or ephedrine into the erect corpora. Idiopathic cases are treated by aspiration of the and lavage of the corpora with dilute heparin solution concomitant with the shunting of blood from the corpora cavernosa to the flaccid corpus spongiosum. Shunting can be accomplished percutaneously by introducing a biopsy needle through the glans penis into the end of each corpus cavernosum and removing a common core of tissue from each. Should the latter prove unsuccessful more formal shunting procedures to the saphenous vein can be performed. Clinical Pathology. Penile Carcinoma. Carcinoma of the penis is relatively rare in the United States but worldwide is a significant health problem. Almost exclusively squamous cell carcinomas, these cancers occur most frequently in the uncircumcised population. Staging is based upon depth of invasion and the presence or absence of inguinal adenopathy. Urologic Management. Penile Carcinoma. As with other neoplasms, management entails consideration of multiple factors including age, general health and clinical stage of the disease. Superficial carcinoma in situ, Erythroplasia of Queyrat, develops as a velvety red patch on the glans or foreskin. Treatment is usually successful with topical application of 5Fluorouracil. Circumcision is adequate treatment for small carcinomas limited to the foreskin. Deeper and more extensive lesions require partial or even total penectomy. Ilioinguinal lymphadenectomy (groin dissection) may be necessary for adequate surgical treatment if clinical lymphadenopathy is present. If lymph nodes are not removed at the time of penectomy, careful followup of the inguinal nodes is mandatory. Early diagnosis and surgical removal of
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locoregional disease offers the best chance for cure. Metastases to the inguinal nodes worsen the prognosis, and there are few long term survivors if cancer is found in the iliac nodes or beyond. Clinical Pathology. Impotence. Vascular, neurologic, endocrine and psychologic problems can lead to loss of erectile ability. Additionally, Peyronie's disease can lead to impotency. Arterial stenosis either of the large vessels of pelvis or small vessels within the penis can cause erectile dysfunction while premature emptying of the emissary veins (venous leak) leads to rapid detumescence or partial erections. Extensive pelvic surgical procedures such as radical prostatectomy can lead to impotence. Occasionally endocrine dysfunction, prolactin secreting tumors or testosterone failure will lead to impotency. Medications such as Proscar or some classes of antihypertensive medications can lead to impotency. Finally, severe psychological problems can lead to erectile dysfunction.
Urologic Management. Impotency. If side effects of medications or endocrine problems are identified they should be addressed. Fortunately, there are a number of successful measures for the treatment of impotency. Sildenafil (Viagra) a phosphodiesterase inhibitor has revolutionized the treatment of male impotence. An oral medication sildenafil by blocking cGMP breakdown enhances cavernous smooth muscle relaxation needed for erection. It is generally well tolerated but must not be given to men taking nitroglycerin containing medications. The external vacuum pump is a popular device utilizing a plastic cylinder enclosing the penis which is connected to a manual pump to create a "vacuum" leading to vascular engorgement and erection. Maintenance of tumescence is dependent on rubber rings slipped onto the base of the penis. The vacuum device is effective and requires no surgical intervention. Some patients find the approach cumbersome and the use of constricting rings around the base of the penis uncomfortable. Another widely used nonoperative approach to the treatment of impotence is the use of intracorporeal injection of vasodilating agents such as papaverine or prostaglandin E1. The use of needles to inject medication into the penis is a psychologic barrier to some patients and this approach is not without complications, specifically, pain, priapism or the development of corporeal fibrosis. Surgical intervention is an alternative option. A number of penile prostheses are available for implantation. The most popular consists of inflatable cylinders inserted
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into the corpora cavernosal bodies, a reservoir implanted behind the rectus muscle for the storage of inflating fluid and a manual pump placed in the scrotum for fluid transfer. Mechanical failure over time is the main complication of these devices. TESTES AND EPIDIDYMIS Clinical Anatomy. The testes and epididymis lie within the scrotum attached to the abdominal wall by the spermatic cord. Production of spermatozoa takes place within the seminiferous tubules while the interstitial Leydig cells synthesize and secrete testosterone. The epididymis, located caudally (behind) the testis are connected to the testes by the rete testes and serve as sites for maturation of spermatozoa, a maturation which is necessary for fertilization. Clinical Pathology. Infection/inflammation/torsion Both infection and inflammation of the scrotal contents are commonly encountered clinical problems. Epididymitis an extremely painful clinical problem occurs much more frequently than orchitis. Bacteria reaching the epididymis by retrograde ascent through the vas deferens may be responsible for some cases but in others no organism can be found. If untreated or severe, the infection can spread to the testes. Isolated orchitis is uncommon but can result from infection by the mumps virus. Torsion of the testicle, a surgically treatable problem must be considered in the evaluating the patient with the acutely painful scrotum. Urologic Management. Infection/inflammation/torsion. In the management of epididymoorchitis, differentiation from testicle torsion is imperative. History and clinical examination are helpful. Torsion is commonly seen in the prepubescent nonsexually active male. Fever, pyuria and gradual onset of symptoms are much more common in cases of epididymitis. On physical examination, the "lie" of the testicle and epididymis are important. A high riding testicle is associated with testicular torsion although pain and associated hydrocele may not allow for this determination. Transscrotal ultrasound with doppler flow are adjunctive studies but should the diagnosis remain in question surgical exploration must be undertaken. If it is clear that epididymitis is the cause of the patient's complaints, treatment includes oral antibiotics, antiinflammatory agents and bed rest. Should the patient appear septic, hospitalization, intravenous antibiotics and at times surgical drainage may be necessary.
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Clinical Pathology. Male Infertility. Problems with the production or transportation of spermatozoa can lead to male infertility. Spermatogenesis is dependent on an intact pituitary-testes axis while sperm transportation requires a patent pathway (vas deferens) to the posterior urethra and ejaculatory mechanism. Urologic Management. Male Infertility. A complete history and physical examination may provide insight into the etiology of male infertility. Previous inguinal surgery, undescended testes, radiation exposure, systemic chemotherapy or industrial toxin exposure may lead to impaired spermatogenesis or sperm transport. Retrograde ejaculation occurs in diabetics as well as patients who have undergone retroperitoneal lymphadenectomy and results in failure of seminal emission. Physical examination include an evaluation for adequate virilization, size of testes and phallus and presence of a varicocele. A semen analysis with attention to volume, sperm number, motility, morphology and presence of fructose is an integral part of the evaluation as is a serum FSH and LH. Should a variocele be present, surgical correction is usually recommended since semen quality often will improve after surgery. Azoospermia, the complete absence of sperm in the ejaculate associated with an elevated FSH occurs with primary failure of spermatogenesis. This can be confirmed by testicular biopsy. However, azoospermia in the presence of a normal FSH suggests blockage of sperm egress which can be corrected if the site of obstruction is identified with vasography. The absence of fructose in the ejaculate occurs with congenital absence of seminal vesicles which can be confirmed on transrectal ultrasound. Clinical Pathology. Testes Tumor. Both malignant germ cell and non-germ cell tumors arise in the testes while malignant tumors of the epididymis are extremely rare. Non-germ cell tumors of the testes include Leydig cell and Sertoli cell tumors, both of which are uncommon. Germ cell tumors which make up the majority of testicular tumors are either seminomas or nonseminomatous. Choriocarcinoma, yolk sac tumor, embryonal cell carcinoma and teratoma are cell types found within the nonseminomatous category. The tumor markers alpha fetoprotein and beta HCG are produced in about 60% of the patients with nonseminomatous tumors. They are most helpful in detection of tumor recurrence after definitive treatment.
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Because of the embryologic development of the testes, arising from the gonadal ridge in the retroperitoneum followed by descent through the inguinal canal into the scrotum, the spread of testes tumor through the draining lymphatics follows this embryonic pathway to the retroperitoneal lymph nodes which surround the aorta and vena cava. Urologic Management. Testes Tumor.
Nonseminomatous Germ Cell Tumors Embryonal Yolk Sac Choriocarcinoma Teratoma
The first step in the management of a patient suspected of having a testicular tumor is establishment of the diagnosis. Classically, a testicular tumor presents as a painless scrotal Suspected Testicular mass. Differentiation from Tumor epididymitis may at times be difficult since hemorrhage or rapid Inguinal approach only. expansion of a testicular tumor may create pain simulating epididymitis. Transscrotal ultrasound is helpful in establishing the diagnosis but surgical exploration will not only establish the diagnosis but also will determine whether the tumor is a seminoma or nonseminomatous tumor. Prior to surgical removal tumor markers should be drawn. An inguinal approach with ligation of the cord at the internal ring, removal of the testes and the surrounding tunica vaginalis should be undertaken. Transscrotal biopsy or removal of a testicular tumor violates the lymphatics of the area complicating future surgical care. Once the testicle is removed and cell type determined, metastatic evaluation is completed. Coaxial tomography of the abdomen and if indicated the chest are performed to determine the extent of retroperitoneal and mediastinal lymph node disease as well as visceral organ involvement. Seminomas are very radiosensitive tumors, thus, irradiation of the retroperitoneal and if necessary mediastinal lymph nodes is standard therapy. The current treatment of nonseminomatous testicular tumors has evolved from the introduction of highly successful cis-platinum based chemotherapy in the 1970's. When the post orchiectomy CT shows no adenopathy (clinical stage I) and markers have returned to normal, a limited retroperitoneal lymphadenectomy is recommended to adequately stage the disease. Should microscopic disease (Stage IIa) be found some centers recommend adjuvant chemotherapy. If bulky retroperitoneal disease (Stage IIb,c) is demonstrated with CT staging after inguinal orchiectomy or pulmonary metastases are seen (Stage III), combination chemotherapy is instituted prior to any surgical intervention. Usually 3-4 courses of combination chemotherapy is given followed by
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evaluation of the response through repeat CT scanning. Should the CT "normalize", further surgery may be avoided. However, if residual lymphadenopathy is found, retroperitoneal lymphadenectomy, removal of the lymph nodes surrounding the infrarenal aorta and vena cava is performed. In about a third of these patients lymph nodes will contain residual cancer in which case additional chemotherapy is given, a third will contained so-called mature teratoma and a third simply fibrous tissue. Neither of the latter two require additional chemotherapy. Careful followup of all patients is critical. For patients with nonseminomatous tumors, tumor markers and chest x-rays are obtained monthly for one year, bimonthly for another year and then semiannually through the fifth year. After the fifth year patients are monitored in a similar fashion yearly. Most recurrences are seen within the first two years after treatment. PEDIATRIC UROLOGY Pediatric urology has evolved into a specialty within the broader field of general urology. Although the pediatric patient can present with the same clinical problems seen in the adult, treatment must be tailored to accommodate patient size and physiologic needs as well as psychological development. In addition, a number of congenital genitourinary problems are more commonly encountered in the pediatric age group. ADRENAL Clinical Pediatric Pathology. Adrenal Hyperplasia. Congenital errors in adrenal steroid production can lead to female pseudohermaphroditism and precocious puberty in the male (although male pseudohermaphroditism can also occur when the enzyme deficiency is the 3BOH steroid dehydroxygenase or 17a hydroxylase deficiency). The two principal enzyme defects in adrenal cortisol production leading to this disorder are the 21-hydroxylase deficiency and the 11 B-hydroxylase deficiency. In the female patient, phallic and labial/scrotal development with a hypospadiac urethra occurs to varying degrees and may be associated with salt wasting or retention depending on the metabolic defect. The female internal genital organs are mullerian (ovaries, uterus). In the male, the diagnosis is usually not made at birth but is associated with prepubescent masculinization in cases of 21-hydroxylase or 11 B-hydroxylase deficiency.
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Urologic Management. Adrenal Hyperplasia. Medical management of both male and female patients includes oral cortisone. In the female, clitoral reduction and vulvovaginoplasty may be necessary depending upon the extent of virilization. (See section on Intersex). Clinical Pediatric Pathology. Neuroblastoma. Neuroblastoma, a tumor arising in neural crest cells which give rise to the sympathetic ganglia and adrenal medulla, usually develops early in life. The majority of the tumors develop within the abdominal region and of these the major site is the adrenal. Approximately 50% of these tumors present in children under the age of 2 and 75% occur within the first 4 years of life. An abdominal mass is the most common presenting symptom. Release of catecholamines by these tumors can lead to headaches, hypertension, palpitations and sweating. Urologic Management. Neuroblastoma. Establishment of the diagnosis is central to the treatment of neuroblastoma. Urinary spot test for VMA, vanillylmandelic acid, is positive in about 75% of patients with neuroblastoma. A 24 hour urine collection for vanillylmandelic and homovanillic acid confirms the diagnosis. Intravenous pyelography may show calcification within a mass displacing the kidney, a finding which is more common in neuroblastoma than in Wilms' tumor. Coaxial tomography is usually confirmatory and calcification are readily seen. Bone marrow aspiration is part of the workup of all children with neuroblastoma as this test is positive in up to 70%. Treatment is surgical and survival is relative to resectability. Interesting, stage IV-S in which patients present with metastatic disease confined to the liver, skin and bone marrow has a favorable prognosis since spontaneous regression is likely to occur. Clinical Pediatric Pathology. Pheochromocytoma. Pheochromocytoma, a tumor arising from chromaffin tissue present in the adrenal medulla should be considered in the differential diagnosis of the pediatric patient with hypertension. The usual age of presentation is 8-9 years. The most common site of origin is the adrenal medulla although chromaffin tissue elsewhere can give rise to these tumors. Bilaterality is more common when this disease occurs in children than adults.
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Urologic Management. Pheochromocytoma. When pheochromocytoma is considered in the differential diagnosis, evaluation should include an ultrasound as a noninvasive screening exam. Urinary catecholamines are obtained as well as VMA and metanephrines. CT is useful in accurate localization of the lesion. Treatment is surgical after adequate preparation with volume expansion and alpha blockers. Clinical Pediatric Pathology. Adrenal adenoma/carcinoma. The adrenal can give arise to cortical adenomas or carcinomas. Functioning adenomas and carcinomas may result in Cushing's syndrome, virilization or rarely feminization. Urologic Management. Adrenal adenoma/carcinoma. Diagnosis can usually be confirmed biochemically via the detection of elevation of urinary steroids. The dexamethasone suppression test is useful in establishing the diagnosis. CT is used for localization while treatment is surgical excision. KIDNEY Clinical Pediatric Pathology. Renal lithiasis. Renal lithiasis in children is relatively uncommon and when encountered is usually associated with metabolic or anatomic abnormalities. Primary oxaluria and xanthinuria result from enzymatic defects while cystinuria the most common cause for pediatric stone formation results from a tubular defect in amino acid transfer. Renal tubular acidosis, in its most common forms, Type I and Type II result from a decreased hydrogen excretion in the distal tubule or inability to reabsorb bicarbonate in the proximal tubule, respectively. Type I is associated with calcium wasting in the urine which leads to nephrolithiasis. Urologic Management. Renal lithiasis. The management of renal lithiasis in the child, as in the adult depends upon factors such as stone size, position and composition. Endoscopic, extracorporeal and open surgical approaches to management are similar to those described for the adult (See adult section). Should a metabolic cause for stone formation be determined, treatment is directed at correction and thus prevention. Primary oxalosis is managed with fluids, pyridoxine, magnesium supplements and oral orthophosphates. Medical management of cystinurics includes adequate fluid intake, urinary
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alkalinization and dietary protein restriction. In some cystinurics, D-penicillamine and alphamercaptopropionylglycine which form soluble complexes with the cystine molecule are used. Treatment of patients with Type I RTA includes fluids and correction of the metabolic acidosis with a base along with replacement of potassium and sodium loss which occur as a result of the distal tubular defect. Clinical Pediatric Pathology. Renal Neoplasms/Wilms Tumor. Wilms tumor, a mixed tumor of metanephros and mesoderm origin, is the most common renal as well as solid abdominal neoplasm of childhood. Both an inheritable and sporadic form of the disease occurs with peak incidence of 3.5 and 2.5 years respectively. Wilms' tumor may be associated with other congenital anomalies such as hemihypertrophy and aniridia. Prognosis is in part dependent upon histology which may be either favorable or unfavorable. Urologic Management. Wilms Tumor. Abdominal ultrasound and CT are helpful in establishing the diagnosis and staging. Surgical removal is the mainstay of therapy. Chemotherapy with or without radiation is given postoperatively. The combination of chemotherapeutic agents and administration of radiotherapy depends upon the surgical stage of the tumor. For low stage disease the prognosis is excellent with a 90% survival while with advanced disease survival drops to 50% at 4 years. Clinical Pediatric Pathology. Disease/Renal Dysplasia. Multicystic Kidney
Another renal cause for an abdominal mass is multicystic disease of the kidney. With the increasing use of perinatal ultrasound, this anomaly can be identified before birth. The exact cause of the problem is unclear but results in a nonfunctioning kidney which has been classically described as a cluster of grapes. Multicystic disease is part of a spectrum of congenital abnormalities of the kidney, the renal dysplasias, which include infantile polycystic kidney disease, a rare fatal autosomal recessive abnormality. Urologic Management. Multicystic Kidney Disease. The management of the asymptomatic multicystic kidney is controversial. Before the era of modern ultrasound and CT, multicystic kidneys were removed when surgical exploration was necessary to establish the diagnosis. With the advent of modern imaging, the diagnosis can be established without surgery. Since the risk of developing
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complications within this type of dysgenetic kidney appears to be low, nonoperative management has been advocated. Clinical Pediatric Pathology. Renal Infection. Renal infection (pyelonephritis) in the pediatric group is suspected when the classic signs of fever, pyuria and flank pain appear. In the infant, the diagnosis may not be apparent being only manifested by fever and increased irritability. Gram negative organisms are responsible for renal most infections. Urologic Management. Renal Infection. Treatment is dependent upon clinical parameters including age, extent of dehydration and general appearance of the patient. If the child is toxic, urine is obtained for culture and sensitivity followed by administration of antibiotics, usually an aminoglycoside and synthetic penicillin until organism and sensitivities have been determined. Both ureteral vesical reflux and obstructive uropathy must be considered in the child who develops pyelonephritis. The combination of infection and increased intrapelvic pressure as may occur with ureteral vesical reflux can lead to parenchymal damage and scarring in the developing kidney and thus aggressive treatment and preventive measures are warranted.
URETER Clinical Pediatric Pathology. Ureteropelvic Junction Obstruction. The ureteropelvic junction (UPJ) is a common site of renal obstruction. Discovery of the problem may occur during pregnancy if prenatal ultrasound is used or later in childhood. Obstruction can be either intrinsic and associated with abnormal ureteral muscle development or extrinsic resulting from aberrant vessels. The clinical presentation covers a wide spectrum and includes a flank mass in the neonate, infection or hematuria. Older patients complain episodically of abdominal or flank pain. Intravenous pyelography, ultrasound and renal scan (often with Lasix to induce a diuresis) are used to establish the diagnosis.
UPJ Obstruction
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Urologic Management. Ureteropelvic Junction Obstruction. The treatment of the obstructed ureteropelvic junction is surgical. The stenotic segment is bypassed either by removal of the involved segment and reanastomosis (dismembered pyeloplasty) or by transposing a flap of redundant renal pelvis to widen the narrowed area. Clinical Pediatric Pathology. Megaureter. In the pediatric population, the normal ureter should have a diameter that is less than 7mm. A wide and tortuous ureter in a child, a megaureter may result from obstruction, reflux, a combination of reflux and obstruction or a combination of lower tract pathologies. A primary obstructed megaureter is one in which an adynamic segment of distal ureter results in obstruction. Clinically, patients with a primary obstructed megaureter can present with infection, pain or an abdominal mass. A primary unobstructed, nonrefluxing megaureter also exists and as the name suggests the ureter is dilated but not obstructed or refluxing. Urologic Management. Megaureter. Both endoscopic and radiographic techniques are used in the evaluation of the patient with a megaureter. Infra- as well as intravesical pathology can be evaluated endoscopically. Voiding cystourethrography is used to detect reflux. Nuclear scans are especially helpful in determining whether ureteral obstruction is the cause of ureteral dilatation. Should the renal scan be equivocal, percutaneous renal perfusion studies (Whitaker test) measuring intrarenal pressures while infusing fluid can be performed. Treatment of the primary obstructed non-refluxing megaureter is surgical. The adynamic segment is resected and the ureter is reimplanted in the bladder. Clinical Pediatric Pathology. Ureteral Duplication. Ureteral duplication is a common congenital anomaly. Incomplete duplication in which both ureteral segments empty into a common ureter occurs in about one in every 125 individuals whereas complete ureteral duplication occurs in every 500 to 600 births. If one of the ureteral components in a completely duplicated system empties outside the trigone that part of the ureteral system is referred to as ectopic. The lower pole ureter of a completely duplicated system may reflux while the upper pole segment, especially when ectopic can be obstructed leading to nonfunction. Incomplete ureteral duplication usually causes no symptoms. Complete duplication is may be found during the
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evaluation of recurrent infection. Additionally, in the female patient, an ectopic ureter emptying into the urethra or vagina can lead to incontinence. Urologic management. The Duplicated Ureteral System. Since an incomplete duplication rarely leads to clinical problems, no treatment is necessary. An obstructed nonfunctioning upper pole segment of a duplicated system is treated by surgical removal. Reflux is most commonly associated with the lower pole segment of a complete duplication and is corrected by ureteral reimplantation in the bladder. Clinical Pediatric Pathology. Ureterocele. A ureterocele represents another congenital abnormality of the ureter which can cause infection, obstruction or reflux. A cystic intravesical (at times intraurethral) dilatation of the most distal ureter, a ureterocele may be found in both single and duplicated ureteral systems. The cause is poorly understood. Urologic Management. Ureterocele. The management of a ureterocele is surgical, however the extent of the surgery must be tailored to the clinical situation. Some ureteroceles can be treated with simple endoscopic incision of the cystically dilated distal ureter while others require extensive reconstruction especially when associated with a duplicated system.
BLADDER Clinical Pediatric Pathology. Infection. Cystitis, infection of the urinary bladder can occur at any age throughout childhood. When not associated with the clinical spectrum of pyelonephritis, cystitis has no long term consequences. Asymptomatic bacteriuria, in the absence of reflux is usually not of clinical concern especially in the older child where it will clear without treatment. Urologic Management. Infection. Treatment of cystitis is based upon culture and sensitivity. Urologic management of the child with recurrent infection initially centers upon determining whether there is an underlying anatomic or neurologic abnormality. In addition to a detailed voiding history, physical examination should include a careful physical examination of
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the sacral area which may suggest congenital defects of the sacral cord. Ultrasonography, intravenous pyelography and voiding cystourethrography complement the detailed voiding history and physical exam. Should an underlying anatomic defect be discovered, treatment is aimed at correction. Clinical Pediatric Pathology. Bladder Stones. Primary bladder stones are rare in industrialized nations. In some areas of the world, this continues to be a major pediatric problem. Urologic Management. Bladder Stones. Treatment of bladder stones can be either endoscopic or via open surgical techniques and is based upon size and associated anatomic abnormalities. Should an anatomic abnormality be contributing to stone, correction of the anatomic defect at the time of stone removal is warranted. Clinical Pediatric Pathology. Extrophy. Extrophy of the urinary bladder is part of a spectrum of anatomic deformities which result from lack of ingrowth of the abdominal mesoderm into the cloacal membrane, an embryologic structure which is part of the infraumbilical covering of the developing abdominal wall. In its complete form the bladder mucosa is exposed on the anterior abdominal wall, the pubic symphysis has not fused and the urethra is epispadiac. A lesser degree of the same complex includes epispadius alone. Cloacal extrophy is an extremely rare congenital anomaly in which there are two extrophied hemibladders separated by a bulging cecum and ileal orifice. The tailgut is blind ending. Urologic Management. Extrophy. Correction of the anatomic abnormalities with restoration of normal bladder function and urinary continence as well as normal penile appearance in the male is the goal of treatment. In order to close the bladder and return it to its normal location, osteotomies must be performed to allow the iliac and pubic bones to rotate for closure of the midline defect. Subsequent to the osteotomies, the bladder is closed. Repair of the epispadiac urethra is reserved for the final stage of Bladder Extrophy reconstruction. In a small minority of patients, there is insufficient bladder for closure in which case urinary diversion is performed.
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Repair of cloacal extrophy is challenging for it requires staged reconstruction of the pelvic urinary structures as well as the gastrointestinal tract. Clinical Pediatric Pathology. Vesicoureteral Reflux. Retrograde flow of urine from the bladder to the ureters and kidneys during bladder filling or voiding occurs with vesicoureteral reflux. The principal clinical problem associated with reflux is recurrent urinary tract infections. The combination of infection and reflux in the pediatric age group kidney can lead to renal scarring and loss of renal function. Reflux results from inadequate support of the intravesical portion of the ureteral submucosal tunnel which may be developmental or acquired. If there is a developmental problem leading to a shortened intramural tunnel for the ureter, inefficient coaptation of the ureteral walls during bladder filling and voiding occurs leading to retrograde flow of urine towards the kidney. The degree of reflux can vary from minimal, Grade I, in which urine refluxes only into the ureter during voiding to Grade V, in which reflux results in massive dilation of the entire collecting system. Urologic Management. Vesicoureteral reflux. In addition to voiding cystourethrography which will establish the diagnosis of reflux, intravenous pyelography is important in assessing the architecture of the upper collecting system and kidneys. Cystoscopy is performed in order to visualize the configuration and position of the ureteral orifices. The more lateral the ureteral orifice appears on the trigone and the more "gapping" in configuration, the more severe the reflux is likely to be. Lower grades of vesicoureteral reflux can resolve spontaneously. Children with low grade reflux treated nonoperatively need to be followed to assure that recurrent infections do not occur. Antibiotics are taken until resolution of reflux is demonstrated. Children with higher grades of reflux and those who develop "break through" infections while on prophylactic antibiotics, are candidates for surgical correction. There are a number of open surgical approaches for the correction of reflux, all of which attempt to lengthen and thus increase the support of the intravesical portion of the ureter. Clinical Pediatric Pathology. Neurogenic Bladder. Developmental anomalies of the spinal column and cord result in many cases of neurogenic bladder in children. The most common of these is the meningomyelocele. Defective innervation of the bladder can lead to inefficient bladder emptying with or without sphincter dyssynergia leading to
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hydronephrosis, infection and stone formation. A large meningomyelocele is readily apparent at birth but occult spinal dysraphic states may be also result in neurologic voiding dysfunction. Urologic Management. Neurogenic Bladder. Treatment is initially directed toward correction of the spinal defect in the newborn with a meningomyelocele. The crede maneuver or intermittent clean catheterization are used to manage bladder emptying until urodynamic evaluation can be completed. Upper tract evaluation should be undertaken through ultrasonography or intravenous pyelography. Sphincter dyssynergia increases the risk of vesicoureteral reflux. Treatment of the neuropathic bladder in the child as in the adult is aimed at maintaining low intravesical pressures and urinary continence. In some patients this can be achieved through a program of intermittent catheterization and pharmacologic manipulation. For others, surgical intervention is necessary to achieve the goals of low pressure storage and continence. Surgical approaches usually entail the use of either large or small bowel segments tailored to augment the bladder, increasing its storage capacity. To increase bladder outlet resistance in the incontinent patient, a number of innovative techniques have been developed. For example, the bladder neck can be tubularized and buried under the bladder mucosa to prevent incontinence. Then, the patient intermittently catheterizes the lengthened and buried neourethra to empty the bladder. Clinical Pediatric Pathology. Enuresis. Involuntary emptying of the bladder beyond the age at which urinary control is expected is termed enuresis. The problem is most commonly associated with bedwetting and is encountered in about 15% of children age 5, after which there is a gradual decrease in the incidence. At age 15, 1 to 2% of adolescents are enuretics. Uncomplicated enuretics are those with no associated genitourinary pathology, while complicated enuretics have a history of infection, poor urinary stream, neurogenic bladder or encopresis. The cause of uncomplicated enuresis is not understood. Urologic Management. Enuresis. A detailed history of voiding pattern and physical examination are the initial steps in the evaluation of the enuretic child. Examination of the lower spine area is of particular importance looking for cutaneous manifestations of occult dysraphism. Urine culture and urinalysis are also an essential part of the evaluation. Should the history,
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physical exam and urinalysis suggest complicated enuresis, the appropriate evaluation is undertaken including intravenously pyelography, urodynamic studies and if indicated endoscopy. For the uncomplicated enuretic, invasive evaluation is not indicated. There are number of treatment options available for the enuretic child. These including conditioning therapy with alarm systems, counseling and pharmacologic treatment. The latter is most widely used in the United States. Imipramine and desmopressin acetate (DDAVP) have been found to be beneficial in the treatment of the uncomplicated enuretic. Clinical Pediatric Pathology. Bladder Tumor. Transitional cell carcinomas in the pediatric age group are extremely rare. The most common solid tumor of the bladder in the pediatric patient is rhabdomyosarcoma. Most of these appear before the tenth year. Urologic Management. Bladder Tumor. (Rhabdomyosarcoma) Multimodal treatment is required for control of rhabdomyosarcoma arising in the lower genitourinary tract. Both chemotherapy and surgical extirpation are employed. The timing and extent (exenterative vs. biopsy) of surgery in combination with chemotherapy (vincristine, actinomycin-D and cyclophosphamide) is evolving and the subject of randomized cooperative trials.
PROSTATE As opposed to the adult, pathologic conditions rarely arise in the prostate of the pediatric patient. Rhabdomyosarcoma of the prostate is the most common malignancy and is treated as discussed under bladder rhabdomyosarcoma. URETHRA Clinical Pediatric Pathology. Urethral Valves. Urethral valves are a congenital anomaly causing bladder outlet obstruction in the male. The embryology of valves is poorly understood but they arise near the verumontanum of the prostatic urethra and form sail like folds obstructing the egress of urine. Three types have been described, the most common being Type I. The outlet obstruction caused by valves can be severe leading to renal failure. Fifty to seventy five percent of patients with
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valves present during the first year of life, many in the neonatal period. A distended bladder is the most common finding. Urologic Management. Urethral Valves. Management will depend upon the clinical situation. Respiratory distress, renal insufficiency with fluid and electrolyte imbalance and sepsis can result from urethral valves. In the neonatal period, drainage either via the urethra or at times with percutaneous nephrostomies in conjunction with resuscitative measures will need to be instituted to resolve the acute medical problems. Diagnosis can be confirmed with voiding cystourethrography. Definitive treatment is endoscopic via incision of the valve leaflets. Clinical Pediatric Pathology. Hypospadius. Embryologic failure of the urethra folds to close and cover the urethral groove results in a urethral opening which is proximal to the glans, a developmental error called hypospadius. As the opening of the urethra moves farther away from the glans, the "degree" of the hypospadius increases. It should be remembered that the adrenogenital syndrome must be ruled out in the child (female) with hypospadius and nonpalpable testes. Ventral curvature of the distal phallus, common in the hypospadiac penis is termed chordee.
Urologic Management. Hypospadius. Treatment of hypospadius is surgical; a number of techniques have been developed. Most involve the transposition of prepuce and/or penile skin to create a neourethra which is brought to the tip of the glans penis. Additionally, if chordee is present it is released at the time of surgery. Excellent cosmetic and functional results are achieved in the majority of cases. TESTES Clinical Pediatric (Cryptorchidism). Pathology. Undescended Testicle
During embryogenesis, the testicle makes its descent from the retroperitoneum through the inguinal canal and into the scrotum. A cryptorchid or undescended testicle fails to reach the intrascrotal landing site with about 10% lying inside the internal ring, 50-70% high in the scrotum and the
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remainder within the inguinal canal. (An ectopic undescended testicle [3-4% of undescended testes] is found outside the normal path of testicular descent). Cryptorchidism is more frequently encountered in the premature infant than one of full term. Bilateral cryptorchidism represents a special situation in which the clinical problem of intersex must be considered. Urologic Management. Cryptorchidism. During the initial evaluation, it is important to determine that the testicle is truly undescended and not simply retractile. In the premature infant, descent of the testes can be anticipated within the first six months. If the testicle is not palpable (or become palpable), it may be necessary to employ CT scanning, MRI or laparoscopy to determine its position. In cases of bilateral undescended testes, should intersex not be the case, serum gonadotrophin levels and serum testosterone levels after HCG stimulation are useful for confirming the presence of viable testicular tissue. Hormonal treatment with intramuscular human chorionic gonadotrophin (hCG) can result in testicular descent and is often the first step in management. Surgical treatment entails mobilization of the testicle and cord with repair of the associated hernia (patent processus vaginalis) and fixation of the testicle dependently within the scrotum.
Clinical Pediatric Pathology. Testicular Torsion. Torsion of the testicle can occur at any age but is most common in the years immediately preceding pubescence. The problem stems most frequently from an excessive "investment" of tunica vaginalis around the testicle resulting in a "clapper bell" deformity (the testicle and cord are the clapper within the bell of tunica). This anatomy permits the twisting of the testicle and cord structures resulting in ischemia.
Urologic Management. Testicular Torsion. The child presenting with acute testicular pain needs immediate evaluation. When confronted with the clinical situation in which testicular torsion is a clinical possibility, torsion is assumed until proven otherwise. Physical findings supporting the diagnosis of torsion include a high riding testicle within the scrotum, an
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anteriorly rotated epididymis and a horizontal lie of the testicle within the scrotum. These findings may be masked by the development of an acute hydrocele. Testicular Doppler studies or testicular scans are indicated in certain clinical situations but generally the best approach is emergent surgical exploration. At the time of surgery, the testicle is detoured and fixed to the scrotal wall with nonabsorbable suture. The contralateral testicle is similarly transfixed to prevent torsion in the future. Clinical Pediatric Pathology. Testicular Tumor. Testicular tumors of childhood are rare. As in the adult patient, a solid painless mass in the scrotum is the most common presentation. Testicular tumors of childhood, however, differ in histology and natural history from those of adulthood. Yolk sac tumors, teratomas and seminomas originate in the germ cells while Leydig cell tumors and Sertoli cell tumors arise from the testicular stroma. The latter can be responsible for precocious puberty or feminization. Urologic Management. Testicular Tumor. The most common tumor of childhood is the yolk sac tumor for which orchiectomy is the treatment of choice. Serum markers, particularly alpha fetoprotein are useful in monitoring for recurrent disease. The need for retroperitoneal lymph node dissection is controversial. Combination chemotherapy is used in those cases in which extranodal metastatic disease has developed. Teratoma, the next most frequently encountered tumor, has a peak incidence at 18 months. Treatment is orchiectomy which will be curative since metastases have never been reported. Seminoma is extremely rare in childhood but is treated with orchiectomy and if necessary radiation therapy. Leydig cell and Sertoli cell tumors are also treated with orchiectomy. No metastases have been reported in cases of Leydig cell tumors while one has in a case of Sertoli cell. Clinical Pediatric Pathology. Intersex. Intersex refers to a spectrum of pathologic entities in which gender identification is unclear. The etiology may result from chromosomal abnormalities, primary endocrine disorders (principally adrenal), dysgenetic gonads or end organ (external genitalia) failure. Ambiguous genitalia usually is recognized at birth but may be discovered later in life when sexual developmental milestones expected for the assigned gender are not achieved.
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Chromosomal abnormalities occur in true hermaphrodites (ovary & testis present). Disorders of adrenal physiology (congenital adrenal hyperplasia) lead to female pseudohermaphroditism. Male pseudohermaphroditism usually results from failure of the external genitalia to respond to testosterone or more rarely from enzyme (e.g., 3-Bhydroxysteroid dehydrogenase or 17-hydroxylase) deficiencies within the adrenals. Patients with gonadal dysgenesis (streak gonads, ovotestes or dysplastic testes) usually have ambiguous genitalia at birth. Urologic Management. Intersex. Biochemical, radiographic and chromosomal studies are undertaken when the genitalia are ambiguous. Biochemical studies to rule out congenital adrenal hyperplasia are essential since this can be a life threatening problem. Karyotyping will aid in establishing the diagnosis while genitography should be undertaken in all cases of intersexuality. In some patients, gonadal biopsy is necessary. Once the underlying pathology is determined treatment is undertaken. In cases of adrenal hyperplasia steroid replacement will correct the problem. Other intersex problems require gender reassignment entailing surgical genitoplasty.
Urologic Instrumentation Endoscopic diagnosis and treatment employs a variety of instruments. The following is a list of equipment commonly encountered in the practice of urology. Cystoscope: Endoscopic instrument used for visualization of the urinary bladder. Cystoscopes may be rigid consisting of a series of lens or flexible utilizing fiberoptic technology for image transmission. Both can be used for endoscopic procedures but in general the rigid cystoscopes are more versatile. A deflecting element on the rigid cystoscope called an Albarran bridge facilitates the placement of ureteral catheters and other intraureteral devices. Nephroscope: A specialized endoscope designed for the examination of the renal pelvis and upper collecting system. Usually placed through a previously established percutaneous tract.
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Resectoscope: Specialized endoscope used for endosurgical procedures of the prostate (TURP) and bladder (TURB). Most often used for the electro dissection (resection) of obstructing prostatic tissue. Current devices use very high wattage to electrodesiccate (vaporize) periurethral prostatic tissue. Ureteroscope: Endoscopic instrument designed to be placed in a retrograde fashion into the ureter for diagnostic and therapeutic endeavors. May be either rigid or flexible. Small ureteroscopes are sometimes referred to as miniscopes. Urethrotome: Device using a cold knife for the incision of urethral strictures. Modern devices have an optical element which permit direct visualization of the strictured area. Lasers: There are a number of lasers currently used within the specialty of urology. The CO2 laser is used for the treatment of cutaneous lesions (principally condyloma) of the perineal skin. The neodynium YAG (Nd:YAG) laser is a continuous wave laser that that has deeper penetrating power than the CO2 laser. It can be used for endoscopic ablation of tissue such as bladder tumors. Currently, it is being explored as an alternative to electroresection (TURP) in the treatment of BPH. The pulse dye laser is a laser which is uses pulses of high energy light to fragment stones through a photoacoustic effect. The Candela Corporation manufactures this laser and ofttimes it is referred to as the “Candela” laser (a misnomer). Electrohydraulic lithotripter: A spark gap generator creates a strong shock wave under water. Propagation of the shock wave to a urinary stone results in fragmentation. First developed was an intracorporeal device which was used for the treatment of bladder stones or renal stones. In 1980 an extracorporeal device (extracorporeal shock wave lithotripter {ESWL})was developed which allows for noninvasive stone destruction. Ultrasonic lithotripter: An endoscopic high frequency acoustic device used for the intracorporeal destruction of stones. Consists of a “wand” which vibrates at ultrasonic frequency which when placed in direct contact with a stone results in fragmentation. Used with a ureteroscope or nephroscope. Stent: Usually refers to an intraureteral device which maintains the patency of the ureter. Stents come in a wide variety of sizes and configurations. Most popular are those with a J-hook configuration (double J) at either end which prevent expulsion from or retraction into the ureter. Commonly used after endoscopic stone management. Can be used as a method of internal drainage after surgical ureteral repair.
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Sound: Metal device used to dilate the urethra. Filiform and followers: Woven device used for the dilatation of urethra strictures in the male patient. The filiform is a very thin bougie used to bypass the strictured area. A follower, of larger diameter, is then attached to the proximal end of the filiform and gently pushed through the strictured area permitting dilatation. Usually a number of followers of increasing size are used to stretch the strictured area to the desired size.
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