Endoscopic DCR Evaluation, Anatomy and Physiology Gary Kroukamp

Causes of Epiphora by Age Children Congenital nasolacrimal duct obstruction Young Adults Trauma Post herpetic canalicular disease Middle-aged adults Dacryolith Older Adults Primary acquired nasolacrimal duct obstruction

At 5 – 6 weeks tissue develops along the cleft between lateral nasal and maxillary processes. Within this tissue Two solid rods form .A proximal one at the medial canthus and a inferior one at the site of nasal opening.They elongate towards each other At 12 weeks segmental disintyegration takes place At 24 weeks this is complete except for the junction between the two processes which remain incomplete for some time.This junction is called the valve of Hassner.At birth this membrane may still be present.

Lacrimal drainage system anatomy – puncta located 5 mm from medial canthus no lashes medial, lower lid needs to be everted to view

Puncta 5mm from medial canthus On lacrimal papillae No lashes medial Evert lower lid

Canaliculi 2mm vertically oriented Ampulla 8mm horizontally oriented Variable common canaliculus Enters sac at common internal punctum Valve of Rosenmuller

Lacrimal sac Lacrimal fossa 2mm wide (semi-collapsed) 10-15mm long Narrows to meet the nasolacrimal duct

Lacrimal pump Medial canthal ligament limbs surround sac Compress sac with blinking Pumps tears

Nasolacrimal Duct 15mm long Valve of Hassner – near exit Exits into inf meatus

Let us have a look at the anatomy for a moment to familiarise ourselves with the territory The Lacrimal sac rests in a shallow osseus groove nl.lacrimal fossa It’s front edge is the anterior lacrimal crest Post it’s border is the post lacrimal crest

A more lat view clearly demonstrates that the sac is protected by the thick frontal process of the maxillary bone. Posterior to this isn the lacrimal bone which is very thin and can literally be egshelled out of the way.

On this Axial view one gets a better impression of its relationship regarding the middle turbinate.However,the anterior limit of the Mt can very and the uncinate process is a more reliable landmark.

This is the real life view. Bleeding is your greatest enemy This is the real life view.Bleeding is your greatest enemy.I prepare the nose with a 5% Cocaine and adrenalin solution on ribbon gause and then infiltrate submucoperichondrialy with 2% lignocaine with adrenalin. The incision is made over here.The rongeur is slid in submucosally and a bite of bone (frontal process maxillary bone) removed .Exposing the sac.Which is then incised. It is essential to do all this atraumatically so as not to create adhesions.These patients do not allow you to examine them post –op to perform nasal toilette. Good luck if you think they’l be indulging in nasal lavage. The Crawfords tube is left in for anything up to a year.Removal requires a GA

Congenital Anomalies Atresia Amniotocele Absence of valves Canalicular atresia Punctal Atresia Supernumerary Puncta & Canaliculi Facial Anomalies Atresia accounts for 95% Dacryocele rare Pneumatocele

Evaluation of Epiphora Eyelid and eyelash deformities Entropion, extropion, pump, punctum Exclude dacryocystitis Inflammation, pus, mucocoele Slit lamp examination Lacrimal system Dye disappearance test, Palpation of canaliculus, Lacrimal irrigation Nasal examination