Impact of external dacryocystorhinostomy on corneal aberrations and optical quality in primary acquired nasolacrimal duct obstruction.

PURPOSE

To assess the impact of external dacryocystorhinostomy (EXT-DCR) on optical quality in patients with primary acquired nasolacrimal duct obstruction (PANDO) by evaluating changes in corneal higher-order aberrations (HOAs) and key optical quality parameters, including modulation transfer function (MTF) and point spread function (PSF).

METHODS

This retrospective study included 26 eyes of 26 patients who underwent unilateral EXT-DCR for PANDO. Preoperative and 6-month postoperative assessments included best-corrected visual acuity (BCVA), manifest refraction spherical equivalent (MRSE), and epiphora severity (Munk score, fluorescein dye disappearance test [FDDT]). HOAs, MTF, and PSF were analyzed at 3 mm and 6 mm pupil diameters using Sirius corneal topography. Paired t-tests, Wilcoxon signed-rank tests, and Spearman correlation analyses were used.

RESULTS

Postoperatively, HOA significantly decreased at 3 mm (0.183 ± 0.160 - 0.128 ± 0.058 µm, p = 0.020) and 6 mm (0.744 ± 0.350 - 0.641 ± 0.271 µm, p = 0.039). Spherical aberration at 6 mm also significantly decreased (- 0.237 ± 0.203 - - 0.194 ± 0.247 µm, p = 0.032). MTF and PSF values showed no significant postoperative changes (p > 0.05). Correlation analysis of Δ values (preoperative-postoperative changes) revealed significant associations between reductions in Munk/FDDT scores and improvements in HOA and spherical aberrations (p < 0.05).

CONCLUSION

EXT-DCR may significantly improve optical quality by reducing HOAs and spherical aberrations. The correlation between epiphora resolution and optical quality suggests that stabilizing the tear film plays a key role in reducing optical distortions. While MTF and PSF values did not show significant changes, further studies with larger cohorts and advanced imaging techniques are warranted to explore the broader impact of lacrimal surgery on visual function and contrast sensitivity parameters.