INTERVENTIONAL RADIOLOGY

Short notice on non-vascular INTERVENTIONAL RADIOLOGY Presented by Hisham S. Wahba Ass. Lecturer of radiodiagnosis National Cancer Institute, Cairo University INTRODUCTION    Interventional radiologists are doctors who specialize in minimally invasive, targeted treatments that have less risk, less pain and less recovery time compared to open surgery. They use their experience to map out the procedure tailored to the individual patient to treat diseases at the site of the illness nonsurgically. Interventional radiology is a recognized medical specialty by the America Board of Medical Specialties. INTRODUCTION     GOAL -------> simplify treatment in a way that minimizes patient discomfort, renders general anesthesia unnecessary, lowers the incidence of morbidity and mortality, and decreases the length and cost of hospitalization. Special procedures can replace surgery (embolization of bleeding ulcers). Others can complement surgery (postoperative abscess drainage). Certain procedures can be used in the management of conditions for which there is no surgical solution (selective chemotherapy). INTRODUCTION INTERVENTIONAL RADIOLOGY VASCULAR NON VASCULAR PERCUTANEOUS BIOPSY ABSCESS DRAINAGE PERCUTANEOUS NEPHROSTOMY PERCUTANEOUS BILIARY DRAINAGE RADIOFREQUENCY ABLATION DIAGNOSTIC THERAPEUTIC NON-VASCULAR TECHNIQUES  Interventional radiology operating theater. PERCUTANEOUS BIOPSY Fine Needle Aspiration Cytology (FNAC) True Cut Core Biopsy FNAC and True Cut Core Biopsy Indications    Presence or absence of disease. Nature of disease (neoplastic, inflammatory, infectious). Extent of disease. FNAC and True Cut Core Biopsy Contraindications  Abnormal coagulation profile ---Elevated prothrombin time (PT). ---Elevated partial thromboplastin time (PTT). ---Depressed platelet counts. ---Low prothrombin concentration (PC). FNAC and True Cut Core Biopsy Patient preparation      Informed consent. Normal bleeding profile. Start clear liquid diet, the night before the procedure. Anxiolytic agents (anxious patients, severely painful biopsies like bone, infants). Sterilize the puncture site, drape the surrounding area. FNAC and True Cut Core Biopsy Equipment   FNAC ----- spinal needles (20 – 22 Gauge) True Cut Core Biopsy ----- true cut biopsy needle (unicut 16G 15cm), gun biopsy needle (speedybell 18G 20cm). 1 2 3 FNAC and True Cut Core Biopsy Technique      Ultrasound or CT guided. Precise lesion site. Apply local anaesthetic (1 % lidocaine) subcutaneous (True Cut Biopsy). Insert needle under guidance. Cytopathologist at biopsy procedure can minimize number of passes. FNAC and True Cut Core Biopsy Complications    Pain and discomfort. Hemorrhage (heamatoma). Pneumothorax (lung biopsy). PERCUTANEOUS ABSCESS DRAINAGE Percutaneous Abscess Drainage Patient preparation    Normal bleeding profile. Fasting for at least 6 hours. Sterilize the puncture site, drape the surrounding area. Percutaneous Abscess Drainage Technique      Subcutaneous lidocaine 1 % injection. Image guided needle placement. Guide wire introduced through sheathed needle. Catheter (pigtail) advanced over guide wire. Catheter fixed in place. PERCUTAEOUS NEPHROSTOMY Percutaneous Nephrostomy Indications   DECOMPRESSION ---Stone ---Stricture ---Tumor URINOMA Percutaneous Nephrostomy Equipments     Needle (PTC catheter set) 19 G 25 cm Guide wire 0.38’’, 150 cm (Teflon). Dilators, 6F, 8F, 10F and 12F. Pigtail catheter (nephropur) 8F. Percutaneous Nephrostomy Patient preparation     Labs: CBC, Coagulation Profile, serum Creatinine, BUN, urine culture and ECG. Ultrasound: determine location of kidney, degree of hydronephrosis. Patient sedation if anxious. Skin sterilization. Percutaneous Nephrostomy Technique      Patient lies in prone position. 1 % lidocaine injection. Needle inserted under US guidance. Tocar withdrawn. Contrast media injected through needle sheath (opacify pelvi-calyceal system) under fluoroscopy.      Guide wire introduced through needle sheath. Sheath withdrawn. Dilator inserted successively (6F12F). Catheter advanced upon guide. Catheter fixed insitu. Percutaneous Nephrostomy Catheter Maintenance      Catheter skin site clean and dry. Exchange and maintain bag in aseptic manner. Bag always lower than kidney to ensure proper gravity drainage. Call radiologist if any symptoms or signs of drain obstruction occurs. Drains changed at 2 to 3 months intervals. Percutaneous Nephrostomy complications      Occlusion of nephrostomy drain. Displaced nephrostomy catheter. Hemorrhage. Sepsis. Urinoma. PERCUTAEOUS BILIARY DRAINAGE (PTD) PERCUTAEOUS BILIARY DRAINAGE EQUIPMENT     Needle (PTC catheter set) 19 G 25 cm Guide wire 0.38’’, 150 cm (Teflon). Dilators, 6F, 8F, 10F and 12F. Pigtail catheter 8F. PERCUTAEOUS BILIARY DRAINAGE Causes of bile duct obstruction      Cancer pancreas. Gallstones. Strictures Cholangiocarcinoma. Sclerosing cholangitis.       Cancer gall bladder, CBD, ampulla. Liver abscess. Duodenal diverticulum. Caroli’s disease. Retroperitoneal fibrosis. Parasites. PERCUTAEOUS BILIARY DRAINAGE Patient preparation      Normal coagulation factors (PC > 75%). Clear fluids after midnight. Fasting at least 6 hours. Prophylactic antibiotic for 12 to 24 hrs. Written consent. PERCUTAEOUS BILIARY DRAINAGE Technique      Skin sterilization. Local anesthetic (1% lidocaine). 3 mm stab to skin made by surgical blade. Needle advanced parallel to table top from a point at Rt 9th intercostal space at midaxillary line. Small amount of contrast injected through needle while it is slowly withdrawn under fluroscopy.      We can use US guidance as alternative to point to dilated biliary radicle. When contrast fills biliary tree, a guide wire is advanced through needle under screen till reaching the CBD. Dilators are applied successively (6F- 9F). Finally, pigtail catheter (external drain) is inserted. Catheter then fixed to skin PERCUTAEOUS BILIARY DRAINAGE Complications    Sepsis and bleeding. Hemobilia. Punturing extra-hepatic structures. PERCUTAEOUS BILIARY DRAINAGE Prevention of Complications      Use 22 or 21 Gauge needles. Take care not to puncture gall bladder and colon. Keep contrast volume to a minimum to prevent rise in bile pressure. Use potent antibiotic coverage before and during PBD. Keep patient well-hydrated. RADIOFREQUENCY ABLATION Liver Lung Radiofrequency Ablation Liver Physical background   Basics of RFA: RF energy is an alternating current with a frequency of 10-900 MHz. RF waves have long WL and as such are of a very low energy. Radiofrequency Ablation Liver Physical background   RF energy effect on body tissues: When RF electric field is applied to the body, the interaction losses in moving ions and water molecules at a frequency of the electric field, creating conduction current.  The friction and ionic agitation generate heat that is produced within the tissues near the electrode called “resistive heat”. Radiofrequency Ablation Liver Physical background   Induction of Coagulative necrosis: The aim of tumour ablation therapy is to destroy the entire tumour by using heat to kill malignant cells and including 0.5-1 cm safety margin.  The aim for RF ablation is achieving and maintaining a 50-100ºC-temperature range throughout the entire target volume. Radiofrequency Ablation Liver Indications     Disease confined to the liver, without evidence of vascular invasions or distal metastases. Tumour size should be ideally smaller than 4 cm. PC > 50% and a platelet count > 50,000/mm3. No other site of metastases in colorectal carcinoma metastases. Radiofrequency Ablation Liver Approaches    Percutaneous approach, is the least invasive, with minimal morbidity, can be performed on an outpatient, requires only sedation, and can be repeated. Laparoscopic approach, Open surgical approach, has associated morbidity and mortality of an open procedure and general anaesthesia, and the technique is a one shot therapy. Radiofrequency Ablation Liver Imaging interpretation & follow-up    AFP for HCC and CA19.9 for CR metastases are of limited value for assessing tumour response because patients with small tumors may have normal pretreatment levels. So, the evaluation of therapeutic effect is based mainly on findings of imaging studies, which accurately reflect the efficacy of ablation. The US shows hyperechoic area replacing the original lesion. This feature, however is unreliable for assessing the outcome of treatment. Radiofrequency Ablation Liver Imaging interpretation & follow-up     Spiral CT imaging: Spiral CT is the standard imaging modalities for evaluating tumour response after RFA. Successfully ablated tumours appear as hypodense areas on CT and do not enhance on the arterial and venous phases after contrast injection. Spiral CT may show the presence of a peripheral enhancing halo surrounding the treated lesion. Radiofrequency Ablation Liver Imaging interpretation & follow-up    This halo is due to the hyperemia and the inflammatory reaction along the periphery of the ablated area. This enhancing halo is depicted several days after treatment and usually disappears 1 month later. A standard protocol for the follow-up of treated cases should include at least a spiral CT study of the liver every 3-4 months . Radiofrequency Ablation Liver Complications 1. 2. 3. 4. 5. 6. 7. 8. Bleeding. Infection. Biliary tract damage. Liver failure. Pulmonary complications. Dispersive pad skin burns. Hepatic vessels injury. Electrode track seeding. Radiofrequency Ablation Liver Eligibility Criteria     Inclusion criteria: Unresectable hepatic malignancies. No evidence of extrahepatic disease. Absence of vascular or biliary invasion. Absence of ascites. PC > 50% and a platelet count > 50.000/mm3. Tumour < 7 cm in size and < 5 in number. No history of hepatic encephalopathy. Tumours in position where the electrode can be inserted and held safely. Informed written consent.       Radiofrequency Ablation Liver Eligibility Criteria  • • • • • Exclusion criteria: Extrahepatic metastasis. Tumours > 7 cm in size or > 5 in number. PV or HV thrombosis, or biliary duct invasion. PC < 50%, and platelet count < 50.000/mm3. Presence of uncontrollable ascites. Radiofrequency Ablation Liver Ablation system  1. 2. 3. RF 2000 system ( RadioTherapeutics Corporation) which consists of: RF generator with frequency of 460 kHz and an output of 100 W. It has a front panel for the power, time, and impedance. LeVeen electrode (3.5 cm arrays) which is insulated cannula housing 10 expandable curved electrodes that, when deployed, assume the configuration of an umbrella. Dispersive electrode pads. Radiofrequency Ablation Liver Ablation system Radiofrequency Ablation Liver Ablation technique 1-Pre- ablation assessment:  The patient is fasting 12 hours.  General assessment, to evaluate the patient for suitability of anaesthesia.  Patient is monitored for BP, pulse, respiratory rate.  US assessment: RFA is performed with US guidance. US is performed to determine the tumours, their relations to surrounding structures and to determine if a safe and adequate approach exists. Radiofrequency Ablation Liver Ablation technique 2- System preparation:  The procedure is done in a special sterilized unit containing the ultrasound machine, the services of general anaesthesia, and the RF system.  The dispersive electrodes, are placed on the patient’s thighs and properly connected to the generator.  The patient is draped in the usual sterile manner, and placed in the supine or the left lateral decubitus position depending on the site of the tumour and the planned needle track. Radiofrequency Ablation Liver Ablation technique 3-Anaesthesia and medications:  Local anaesthesia is injected from the entry site to the liver capsule with 10 mL of 2% xylocaine. Skin is pricked by a small lancet.  Patients are treated under general intravenous anaesthesia consisted of a propofol infusion and fentanyl citrate IV injection. 4-Needle electrode placement:  The LeVeen electrode is introduced into the liver and advanced to the target area of the tumour under US guidance with free hand technique. Radiofrequency Ablation Liver Ablation technique 5- Treatment strategy:  The objective in treating the tumours is to ablate the entire tumour with at least 1 cm- safety margin.  Tumours < 2.5 cm in diameter are ablated with placement of the electrode tip in the center.  Tumours of 3 cm in diameter, the needle is advanced to the deepest margin. After ablation of the deep part, the arrays are retracted and the needle electrode is withdrawn to 2 cm.  The arrays are redeployed and the more superficial part of the tumour with anterior tumour-free margin is ablated. Radiofrequency Ablation Liver Ablation technique  To treat larger tumours, multiple ablations are needed to be overlapped to build a composite thermal lesion with sufficient size to kill the entire tumour and to provide 1 cm tumour-free margin. Radiofrequency Ablation Liver Ablation technique 6-Ending RFA treatment:  After the suggested complete ablation of the tumour is achieved, the arrays are completely retracted. The needle track is ablated as the needle electrode is withdrawn, and then the needle electrode is removed.  The anaesthesia is stopped and the patients allowed to recover. Radiofrequency Ablation Liver Post-ablation care     Strong IV analgesics. Patients are observed clinically for 2-3 hours. Prophylactic IV antibiotics is started and continued for 3 days. Before leaving, US is performed to the patients to detect any collection. The skin incision is sterilized and dressed. The patient is allowed to eat after 6-8 hours. Radiofrequency Ablation Liver Conclusion    The use of RFA to treat unresectable liver tumours is unlikely to be curative for many patients; however, a subset of patients treated with RFA may achieve long-term disease-free survival. Longer follow-up is needed to determine long-term disease-free and overall survival rates. RFA of unresectable liver tumour provides a safe and highly effective method to achieve local disease control. Radiofrequency Ablation Liver Case 1 Radiofrequency Ablation Liver Case 2 Radiofrequency Ablation LUNG    New technique under trial in many institutes in the USA and European countries. Many researches concluded that it is an effective and promising technique. RFA is not intended to replace surgery, radiotherapy or chemotherapy. It may be effective when used alone or in conjunction with these treatments. Radiofrequency Ablation Lung Prevalence of lung cancer According to American Cancer Society. “Cancer Facts & Figures 2004.”  Approximately 173,770 new cases of lung cancer were diagnosed in 2004 accounting for 13 % of all new cancer cases.  Lung cancer was accounting for 28 % of all cancer deaths in 2004.  85-95 % of lung cancers are smoking related.  More Americans die each year from lung cancer than from breast, prostate and colorectal cancers combined.  African American men are at least 40 % more likely to develop lung cancer than white males. Radiofrequency Ablation Lung Introduction    Lung cancer is among the most commonly occurring malignancies in the world and one of the few that continues to show an increasing incidence. Patients with advanced lung cancer have a median survival time of 6–8 months and a 1year survival rate of only 10%–20% (Fry WA et al, 1999). Although surgical resection is acknowledged to be the treatment of choice for stage I lung cancer and is the only therapy with any prospect of cure or long-term survival, in practice only about one-third of patients are eligible for surgical intervention (Ginsberg RJ et al, 1998). Many of these patients have poor cardiopulmonary status or poor general health, or they are elderly and therefore considered to be at high surgical risk and are frequently referred for radiation therapy or expectant palliative treatment. Thus, both chemotherapy and radiation therapy have an important role in the treatment of patients with advanced lung cancer (Dupuy DE et al, 2001). Radiofrequency Ablation Lung Introduction  Goldberg et al showed that RF ablation could be used to successfully treat small malignant pulmonary tumor nodules in an animal model and that normal lung tissue rapidly heals from thermal injury. They suggested that RF ablation could offer a minimally invasive method for treating patients with inoperable lung cancer (Goldberg SN et al, 1996). Radiofrequency Ablation Lung Benefits         Usually does not require general anesthesia. Relatively low cost. Is well tolerated. Most patients can resume their normal routine the next day and may feel tired for a few days. It can be repeated if necessary. It may be combined with other treatment options. It can relieve pain. It has a short hospital stay. It has few complications. Radiofrequency Ablation Lung Limitations    If tumor is close to a critical organs like central airways, blood vessels, heart. Large tumors. Tumors at sites difficult to reach. Radiofrequency Ablation Lung Patient preparation        Fasting for at least 12 hrs. Coagulation profile. Written consent. Chest X-ray. CT scan (CT densitometry). Full labs studies. ECG. Radiofrequency Ablation Lung CASE 1 a. pre-RFA. b. During. c. After. Radiofrequency Ablation Lung CASE 2 a. b. c. d. e. Before RFA. 1 months. 3 months. 6 months. 12 months. Radiofrequency Ablation Lung CASE 3 a. b. c. d. e. f. pre-RFA. During. Just after. 1 day. 3 months. 12 months. Radiofrequency Ablation Lung Complications   Major complications including large pneumothoraces that required thoracostomy tube insertion, and persistent hemoptysis. Minor complications including small pneumothoraces, subcutaneous emphysema, obstructive pneumonia, pleural effusion, fever, mild hemoptysis and severe myalgia. Non of these minor complications required further treatment. Radiofrequency Ablation Lung Efficacy   Depending on the size of the tumor, RFA can shrink or kill the tumor. Because it is a local treatment that does not harm much healthy tissue, the treatment can be repeated as often as needed to keep patients comfortable. It is a relatively safe procedure, with low complication rates. By decreasing the size of a large mass, or treating new tumors in the lung as they arise, the pain and other debilitating symptoms caused by the tumors are often relieved.  RFA is a new treatment that has shown early, promising results. THANK YOU