In Vivo Morphology of Nasolacrimal Duct Opening into the Inferior Meatus.

Abstract

To study the in vivo morphology of nasolacrimal duct (NLD) openings into the inferior meatus. Patients undergoing endoscopic dacryocystorhinostomy and lacrimal intubation had endoscopic real-time examination of the NLD opening. Morphology of NLD openings (size, shape, mucosal folds), and their location from the axilla of the inferior turbinate were assessed. Forty-three lacrimal systems of 39 adult patients (11 males, 28 females) with a mean age of 61 years were studied. Thirty-five patients had unilateral involvement, and 74% had anatomical NLD obstruction. Of 43 lacrimal systems, 41 had a visible NLD opening. The majority was sulci shaped (63%, 26/41) followed by fissure type (34%), and 2% had wide-open round morphology. The majority of the openings (93%) were oriented vertically, and 67% (14/21) of the sulci shaped openings continued into gutter like channels along the lateral nasal wall. Mucosal folds were present in 7% (3/41) of the openings along the edges. The mean distance between the opening and the axilla of the inferior turbinate was 3.7± 2.1 mm (median, 3.6; range, 0-7.2). Sulci shaped NLD openings were the most common morphology, and mucosal folds were less commonly observed compared with cadaveric studies.