Angular Variations of the Lateral Nasal Wall as Independent Predictors of Primary Acquired Nasolacrimal Duct...

BackgroundThe aim of this study was to investigate the relationship between specific sinonasal anatomical parameters and primary acquired nasolacrimal duct obstruction (PANDO) using paranasal sinus computed tomography (PSCT).MethodsThis retrospective case-control study included 42 patients with PANDO and 42 controls. Axial and coronal PSCT images were analyzed to measure the anterior medial lacrimal crest-uncinate process angle (AMLC-UP), nasal bone-lacrimal crest angle (NB-LC), and orbital-maxillary wall distance (OMD). Independent samples t-tests and Mann-Whitney U tests were applied based on data distribution. Variables were entered into stepwise binary logistic regression to identify independent predictors of PANDO.ResultsAMLC-UP angle was significantly higher in the PANDO group compared with controls (mean difference 4.04°, 95% CI: 0.34-7.74, P = .033), while NB-LC angle and OMD did not differ significantly. Multivariate analysis identified both AMLC-UP (OR = 0.916, P = .007) and NB-LC (OR = 1.061, P = .030 (Control:1, PANDO:0)) angles as independent predictors of PANDO. An increasing AMLC-UP angle and a decreasing NB-LC angle were independently associated with higher odds of PANDO. OMD was not retained in the final model. The logistic regression explained 14.6% of variance (Nagelkerke R²) with an overall classification accuracy of 61.9%.ConclusionSubtle angular variations between the lacrimal crest, uncinate process, and nasal bone are independently associated with PANDO, suggesting that lateral nasal wall anatomy contributes to nasolacrimal duct patency. These findings may inform preoperative planning for endoscopic dacryocystorhinostomy.