Evaluation of internal nasal valve angle and peak nasal inspiratory flow values in primary acquired nasolacrimal duct obstruction.

PURPOSE: To evaluate the relationship between primary acquired nasolacrimal duct obstruction (PANDO), internal nasal valve angle (INVA), and peak nasal inspiratory flow (PNIF) values.

METHODS

This retrospective clinical study was conducted in a tertiary otorhinolaryngology and ophthalmology clinic. It included 94 eyes of 47 PANDO patients (47 affected and 47 unaffected eyes) and the right eyes of 47 healthy individuals as controls. Individuals with a history of nasal or sinus surgery, pediatric patients, and cases with epiphora but patent nasolacrimal ducts on irrigation were not included in the study. The internal nasal valve angle (INVA) was measured using computed tomography (CT), and peak nasal inspiratory flow (PNIF) testing was performed. CT cross-sectional images were used to assess the diameters and directions (inner/outer) of the lacrimal canals in both sides of PANDO patients and the right side of control participants.

RESULTS

The PNIF value was 76.50 ± 39.08 (20-170) in the PANDO group and 64.47 ± 23.50 (30-110) in the control group, with a significant difference (p = 0.045). INVA was 12.71 ± 3.94 on the affected side and 12.06 ± 3.19 on the unaffected side in PANDO patients, and 11.36 ± 5.63 in controls (p = 0.419). The mean minimum transverse diameter of the bony lacrimal canal was significantly wider on the affected side than the unaffected side and controls (p = 0.005).

CONCLUSIONS

These findings suggest that intranasal airflow dynamics may contribute to the pathogenesis of PANDO, potentially leading to better understanding and management of nasolacrimal duct obstructions.