The Distance between Nasomaxillary Groove and Bony Nasolacrimal Canal in Taiwanese - A Measurement from Sinus Computed Tomography

Abstract

Background: The distance between nasomaxillary groove (NMG) and bony nasolacrimal canal (BNLC) is important in surgeries relating pyriform aperture, such as maxillary surgery using prelacrimal recess approach or rhinoplasty using external osteotomy. The purpose of this study was to measure the distance between NMG and BNLC in Taiwanese adults from axial views of sinus computed tomography (CT). Methods: We retrospectively reviewed sinus CT films of 629 patients from November 2011 to October 2013. Patients who were less than 20 years old or non- Taiwanese were excluded. The distance between NMG and the anterior border of BNLC was measured from axial views of sinus CT by two otolaryngologists. Results: There were 132 patients (74 males and 58 females), 264 BNLCs enrolled in this study. Their age ranged from 20 to 82 years old, with a mean of 48.5 ± 14.5 years. The mean distance between NMG and the upper end of BNLC was 5.8 ± 2.0 mm (range: 1.5 - 12.6 mm). The mean distance between NMG and the lower end of BNLC was 8.2 ± 2.3 mm (range: 3.6 - 14.5 mm). There were no statistically significant differences between those from right and left sides, and those from males and females. Conclusions: To the best of our knowledge, this is the first study to measure the distance between NMG and BNLC measured from sinus CT. Our data provide information for surgeries involved pyriform aperture, such as maxillary surgery using prelacrimal recess approach, rhinoplasty using external osteotomy, or endoscopic sinus surgery.