Efficacy and Complications of Upper Versus Lower Punctal Monocanalicular Intubation in Congenital Nasolacrimal Duct Obstruction

Abstract

Abstract: : Purpose: A monocanalicular intubation system (Monoka tube with Ritleng introducer) has been in use since its introduction in the early 1990's. This retrospective study was designed to evaluate the complications and efficacy of this system, specifically in the pediatric population for the treatment of congenital nasolacrimal duct obstruction. We compare the complications associated with upper lid versus lower lid monocanalicular intubation, and the efficacy of monocanalicular versus bicanalicular intubation. Methods: We conducted a retrospective chart review of nasolacrimal duct surgery performed by one pediatric ophthalmologist during a two-year period between January of 1998 and February of 2000. Results: In our series, 82 intubations of canalicular systems were reviewed. Of these intubations 79%(65) involved monocanalicular intubations. The overall complication rate of monocanalicular intubation was 25%. Of these complications, 62%(13) were found in upper lid intubations. However, of all serious complications 90%(9) were related to upper lid intubation. Overall, 69%(9) of upper lid complications were designated as serious, and only 11%(1) of lower lid complications fell into this category. The complication rate associated with bicanalicular intubation was 8.5%, and success rate was 94%. Monocanalicular intubation was found to have an overall success rate of 82%. Upper punctal intubation has a success rate of 89%, versus 83% in lower punctal intubation. Conclusion: Our experience suggests, that despite the manufacturer's recommendation to place Monoka stents in the upper lid punctum, the pediatric population may experience a lower rate of complications, which are less serious, with lower lid punctal intubation. We propose that this may be due to tighter apposition of the upper punctum against the globe in the pediatric population than in adults. Although bicanalicular intubation systems may have a higher success rate in pediatric patients, the surgical ease of Monoka stent placement with a Ritleng introducer may outweigh the slightly lower success rate of this method. Additionally, use of a monocanalicular intubation for congenital nasolacrimal obstruction enables avoidance of manipulation of both the upper and lower canalicular systems, thus minimizing the possibility of scaring both canaliculi.

Keywords: 410 eyelid • 315 anatomy