title: The intranasal ostium after external dacryocystorhinostomy and the internal opening of the lacrimal canaliculi.
abstract: The purpose of this paper was to evaluate the appearance and location of the healed intranasal ostium and the internal aperture of the common canaliculus after uncomplicated external dacryocystorhinostomy (DCR). In 21 patients who underwent uncomplicated external DCR, the distances between the lacrimal puncta and the internal aperture of the common canaliculus were measured during surgery. The measurements were taken with a 1 mm diameter Bowman probe graded in millimeters. These measurements were recorded and considered the landmarks for the spatial localization of the internal aperture of the canaliculus. After surgery, under endoscopic control, the same method was used to measure the distance between the lacrimal puncta and the internal ostium, which was defined as the aperture through which it was possible to visualize the very first protrusion of the probe into the nose. The intra- and post-operative measurements were compared. Endoscopic photos of the healed endonasal ostium were also taken. The photos showed that when DCR procedures were not complicated by scarring or mucosal adhesions, the lacrimal sac became a depression perfectly integrated within the nasal mucosa. The scar at the site of junction between the nasal and the lacrimal sac mucosa appeared as a large-diameter pearl-like colored frame that surrounded the depression. In the context of the depression a small aperture, which presented a diameter of around 2 mm, could be easily visualized. The spatial location of this aperture corresponded to the internal aperture of the common canaliculus (p < 0.05).
authors.affiliation: Department of Ophthalmology, Orbital Center, University of Amsterdam, Amsterdam, The Netherlands
authors.forename: L
authors.initials: L
authors.lastname: Baldeschi
authors.forename: G J.
authors.initials: GJ
authors.lastname: Nolst Trenité
authors.forename: C
authors.initials: C
authors.lastname: Hintschich
authors.forename: L
authors.initials: L
authors.lastname: Koornneef