The lacrimal system consists of: 1. Secretory part (lacrimal secretory system) 2. Excretory part (lacrimal drainage system) Anatomy of the lacrimal drainage system The lacrimal drainage system is formed of: a. Two puncti: Located at the posterior edge of the lid margin, not seen except when the lid is everted. Each punctum lies 6 mm from the medial canthus on a slightly elevated portion called the papilla. b. Two canaliculi: Vertical part: 2 mm Horizontal part: 8 mm c. Lacrimal sac: The lacrimal sac is formed of: Body: This forms the main part. Fundus: blind upper portion which lies above the medial palpebral ligament. Neck: the neck is narrow and continuous with the nasolacrimal duct. Horner's muscle: is a part of the orbicularis which is inserted into the lacrimal fascia which surrounds the sac. d. Nasolacrimal duct 12-24 mm long Hasner valve in the inf. meatus Precorneal tear film : It's formed of 3 layers: a. Outer lipid layer: secreted by meibomian glands. Function: Prevent rapid evaporation of tears. Lubricates the eyelids over the globe. b. Middle aqueous layer: secreted by the lacrimal gland. Function: Supplies oxygen to the corneal epithelium. Antibacterial as it contains lysozymes. c. Inner mucinous layer: secreted by the goblet cells. Function: Makes the corneal epithelium hydrophilic. Congenital naso-lacrimal duct obstruction Clinical picture: Epiphora, usually noticed at 2-3 weeks after birth. Recurrent conjunctivitis Pressure over the lacrimal sac reflux of clear fluid, mucus, muco-pus or sometimes frank pus. Sticky eye due to delayed canalization of the nasolacrimal duct . Treatment of congenital dacryocystitis: 1. Conservative: antibiotics with hydrostatic massage of the lacrimal sac, 2. Probing is successful if done carefully as the lacrimal passages are still elastic. 3. Repeated syringing & irrigation with saline may cure the condition. 4. Silicone intubation of the lacrimal drainage system may be beneficial 5. Dacryocystorhinostomy (DCR). Acute dacryocystitis Etiology: Predisposing factor: nasolacrimal duct obstruction. Causative agent: Pneumococci, Staphylococci and Streptococci. Symptoms: Severe pain. Fever. Signs: 1. Marked edema and redness of skin over the sac. 2. Regurgitation test: -ve due to congestion of the epithelium of canaliculi. 3. Tender swelling of lacrimal sac. 4. Abscess formation with fluctuation. Complications: 1. Lacrimal fistula: the sac may burst anteriorly through the skin. 2. Pyocele: canaliculi may become obstructed. 3. Orbital cellulitis and cavernous sinus thrombosis. 4. Chronic dacryocystitis. Treatment: 1. During the acute phase: A. Antibiotics: systemic and topical. B. Hot fomentations. C. Lotions: to clean the pus. D. Incision and drainage if an abscess forms. 2. After the acute attack subsides: Dacryocystorhinostomy with fistulectomy if needed. Chronic dacryocystitis Definition: A chronic inflammation of lacrimal sac secondary to obstruction of the naso-lacrimal duct. It is the commonest lacrimal sac disorder. Etiology: Predisposing factor: Nasolacrimal duct obstruction. Causative agent: i. Pneumococci in 80% ii. Staphylococci, Streptococcus, trachoma, and fungi iii. TB and Syphilis: rare Symptoms: 1. Watery eye. 2. Discharge. Signs: Swelling of lacrimal sac below the medial palpebral ligament Regurgitation test +ve: Pressure on the swelling causes regurge of mucous or pus. Expression of mucopurulent material in a patient with chronic dacryocystitis. Complications: 1. Chronic conjunctivitis. 2. Epiphora, eczema and ectropion (vicious circle). 3. Hypopyon ulcer. 4. Endophthalmitis following intraocular operation. 5. Mucocele and pyocele: if the canaliculi are obstructed. 6. Lacrimal fistula. Mucocele in a patient with chronic dacryocystitis Treatment: 1. Treatment of the cause of obstruction: e.g. relieve congestion, removal of a nasal polyp. 2. Dacryocystorhinostomy: operation of choice. Indications of DCR A. Chronic dacryocystitis. B. Mucocele of the lacrimal sac. C. Lacrimal fistula (DCR and fistulectomy) Contraindication of DCR A.Bad lacrimal sac: extensive adhesions and neglected cases. B.Bad nasal mucosa: atrophic rhinitis and polypi. C.T.B and tumors of the sac. D.Hypopyon ulcer. Dacryocystectomy: Idea: removal of the lacrimal sac. Indications: indicated in cases where DCR can't be done. Canaliculitis Characterized clinically by: Persistent epiphora. Chronic conjunctivitis. Patulous lacrimal punctum. On pressure, a mucopurulent discharge which sometimes contains concretions, is seen extruded from the dilated punctum. Oedema of the left canaliculus due to chronic canaliculitis Pouting of the punctum in the patient with chronic canaliculitis. Treatment: Canaliculotomy is the curative method in these cases (slit the posterior wall of the canaliculus, all the fungoid masses are curetted and irrigate with saline). Two-snip procedure for punctal stenosis: (a) vertical cut; (b) horizontal cut; (C) final result . DRY EYE Etiology: 1. Inflammation of lacrimal gland e.g. sarcoidosis. 2. Congenital absence of the lacrimal gland. 3. Tumors of lacrimal gland: e.g. mixed lacrimal gland tumor. 4. Keratoconjunctivitis sicca: autoimmune disease leading to atrophy and fibrosis of the lacrimal gland, it occurs usually in females and may be associated with arthritis and dry mouth (Sjogren's syndrome). 5. Conjunctival scarring: due to trachoma, chemical burns, Stevens-Johnson syndrome and ocular cicatricial pemphigoid. Clinical picture: Irritation and foreign body sensation. Deficient tear production measured by filter paper (Schirmer’s test). 5*35 I : 5 min-N=10-25 -no anesthesia 2 min-N=10-25 –anesthesia (basic) II : (reflex)- 2 min-15 Rose Bengal staining of degenerated epithelium of conjunctiva, cornea and mucus. 1% Punctate epithelial erosion of the cornea. 2% Tear film break - up time (BUT) is diminished. 10 sec Tretment 1.Protective glasses. 2.Tear sub. 3. Punctal occlusion. 4. Corticosteroid (autoimmune dis.). WATERY EYE 1. Lacrimation Lacrimation is over secretion of tears Etiology: Emotional conditions Reflex lacrimation from foreign body or inflammation of the lid margin, conjunctiva, cornea, iris and ciliay body, glaucoma, errors of refraction, and latent squint. 2. Epiphora: Epiphora is overflow of tears onto the cheek due to inadequate drainage due to lacrimal pump failure or obstruction of the lacrimal passages. Etiology: A. LACRIMAL PUMP FAILURE: a. Lid margin: abnormality in posterior border of the lid margin. b. Ectropion. c. Orbicularis muscle: Facial palsy. B. OBSTRUCTIVE EPIPHORA: The obstruction may be: Congenital e.g. punctual atresia, NLD obstruction. Inflammatory e.g. trachoma, herpes, fungal. Traumatic e.g. bony fractures, surgical trauma. Foreign body e.g. lashes Tumours e.g. nasal polyps, maxillary tumours. CLINICAL EVALUATION OF EPIPHORA Exclude causes of excessive lacrimation. Investigations: 1. Regurgitation test: Reflux of pus or tears from the puncti in case of obstruction of the naso-lacrimal duct. 2. Instill a drop of fluorescein in the conjunctival sac and a cotton pellet under the inferior turbinate of the nose. 3. The lacrimal passage is irrigated with saline, if fluorescein is not recovered and saline does not reach the nose, there is complete block. 4. Dacryocystography: A radiocontrast medium is injected and X-ray is done at intervals to detect filling of the lacrimal system. 5. Plain X-ray: for diagnosis of tumors or fractures. Treatment of Epiphora 1. Treatment of the cause: e.g. Ectropion and nasal causes of epiphora 2. Stenosis of puncti and canaliculi: Dilatation and probing 3. Obstruction of Nasolacrimal duct: a. Congenital obstruction: Hydrostatic massage Dilatation and probing Dacryocystorhinostomy b. Acquired obstruction: Dilatation and probing usually fails Dacryocystorhinostomy Dacryocystectomy.
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