Paeds Vivas · ophthalmology
Congenital nasolacrimal duct obstruction — branching viva
Branching viva on congenital nasolacrimal duct obstruction: recognising the white quiet watering eye with reflux on lacrimal-sac pressure, excluding congenital glaucoma, applying the conservative-first Crigler massage management, reasoning through the probing-timing controversy, and escalating the acute dacryocystitis and neonatal dacryocystocele.
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Target exams
Branch 1 — The diagnosis and the mimic
The candidate should identify congenital nasolacrimal duct obstruction from the white, quiet, watering eye with reflux on sac pressure and a normal red reflex and cornea, and immediately name congenital glaucoma as the must-not-miss mimic that also waters but adds photophobia, blepharospasm, a large or cloudy cornea and Haab striae. [4]
Probe the candidate on the mechanism: persistence of the membranous valve of Hasner at the distal duct opening, the last segment to canalise, backing up tears and mucus to overflow as epiphora. Ask why the eye stays white (the infection is confined to the drainage sac and tear film, not the conjunctiva) and why colds worsen it (nasal congestion swells the mucosa around the distal opening). [4]
References4ShowHide
- [4]Schnall BM Pediatric nasolacrimal duct obstruction. Curr Opin Ophthalmol, 2013.PMID 23846190
- [2]Petris C; Liu D Probing for congenital nasolacrimal duct obstruction. Cochrane Database Syst Rev, 2017.PMID 28700811
- [5]Lekskul A; Preechaharn P; Jongkhajornpong P; et al Age-Specific Outcomes of Conservative Approach and Probing for Congenital Nasolacrimal Duct Obstruction. Clin Ophthalmol, 2022.PMID 35698598
- [10]Harris GJ; DiClementi D Congenital dacryocystocele. Arch Ophthalmol, 1982.PMID 7138344