ACQUIRED OBSTRUCTION Flashcards
(21 cards)
Conjunctivochalasis - what is it
involutional process involving the loss of conjunctival adhesion to underlying Tenon capsule and episclera and may be analogous to the conjunctival abnormalities leading to superior limbic keratoconjunctivitis
Conjunctivochalasis - treatment
lubricants and topical steroids • Surgical options include securing the bulbar conjunctiva to the sclera with three absorbable sutures (e.g. 6-0 polyglactin) placed 6–8 mm from the limbus, or excision of a crescent- shaped area of excess bulbar conjunctiva, with an anterior limit of around 6 mm from the limbus
Primary punctal stenosis - causes
chronic blepharitis and idiopathic stenosis; others include herpes simplex and herpes zoster lid infection, local radiotherapy, cicatrizing conjunctivitis, chronic topical glaucoma treatment, systemic cytotoxic drugs such as 5-fluorouracil, and systemic conditions such as porphyria cutanea tarda
Secondary punctal stenosis - when
• Retropunctal (Ziegler) cautery can be used for pure punctal eversion • Medial conjunctivoplasty can be used in medial ectropion • Lower lid tightening, usually with a tarsal strip, is used to correct lower lid laxity
Canalicular obstruction - causes
congenital, trauma, HSV infection, drugs and irradiation
Partial obstruction of the common or individual canaliculi - treatment
simple intubation of one or both canaliculi with silicone stents. These are left in situ for 6 weeks to 6 months
Total individual canalicular obstruction - treatment
Canalicular trephination using a purpose-made minitrephine (Sisler), followed by intubation. Balloon canaliculoplasty and endoscopic laser - less invasive, less success.
Canalicular obstruction with 6–8 mm of patent normal canaliculus between the punctum and the obstruction
anastomosis of the patent part of the canaliculus into the lacrimal sac, with intubation, can be performed (canaliculodacryocystorhinostomy – CDCR)
Canalicular obstruction - where obstruction is severe or it is not possible to anastomose
conventional surgery consists of conjunctivodacryocystorhinostomy and the insertion of a toughened glass (Lester Jones) tube
Nasolacrimal duct obstruction - causes
○ Idiopathic stenosis – by far the most common ○ Naso-orbital trauma, including nasal and sinus surgery ○ Granulomatous disease such as Wegener granulomatosis and sarcoidosis ○ Infiltration by nasopharyngeal tumours.
Conventional (external approach) DCR - when
Nasolacrimal duct obstruction - for obstruction distal to the medial opening of the common canaliculus
Conventional (external approach) DCR - what is it
anastomosis of the lacrimal sac to the mucosa of the middle nasal meatus
Conventional (external approach) DCR - causes of failure
inadequate size and position of the ostium, unrecognized common canalicular obstruction, scarring and the ‘sump syndrome’, in which the surgical opening in the lacrimal bone is too small and too high
Conventional (external approach) DCR - complications
cutaneous scarring, injury to medial canthal structures, haemorrhage, infection and cerebrospinal fluid rhinorrhoea if the subarachnoid space is inadvertently entered
Endoscopic DCR - advantages
less marked systemic disturbance with minimal blood loss and a lower risk of cerebrospinal fluid leakage, the avoidance of a skin incision and shorter operating time
Endoscopic DCR - disadvantage
slightly lower success rate and visualization difficulties, meaning that additional procedures are sometimes needed
Other procedures, often reserved for partial nasolacrimal duct obstruction
probing and intubation, stent insertion and balloon dacryocystoplasty
Dacryolithiasis - signs
Intermittent epiphora, recurrent attacks of acute dacryocystitis and lacrimal sac distension. The lacrimal sac is distended and relatively firm, but is not inflamed and tender as in acute dacryocystitis. Mucus reflux on pressure may or may not be present
Dacryolithiasis - where in lacrimal system
may occur in any part of the lacrimal system
Dacryolithiasis - males or females
males
Dacryolithiasis - pathophysiology
Tear stagnation secondary to inflammatory obstruction may precipitate stone formation, which tends to be associated with squamous metaplasia of the lacrimal sac epithelium
