Five-year effect of sequential argon-Nd:YAG prophylactic laser peripheral iridotomy on corneal endothelial cell density in Japanese eyes with narrow angles.

Purpose: To evaluate the effects of prophylactic sequential argon- Nd:YAG laser peripheral iridotomy (pLPI) on the corneal endothelial cell density (CECD) over 5 years in Japanese eyes with narrow angles (NA-eyes).

Study Design: Prospective observational study METHODS: The CECD of NA-eyes before and after pLPI and of untreated NA-eyes were assessed annually over 5 years with non-contact specular microscopy. Routine ophthalmic examinations and measurements using anterior-segment imaging devices were performed at baseline. The time courses of the CECD were analyzed using a multivariable linear mixed-effect model and factors obtained at baseline.

Results: Sixty-nine pLPI-treated NA-eyes (69 subjects; mean age, 68.9 years) and 67 pLPI-untreated NA-eyes (67 subjects; mean age, 64.4 years) were enrolled. In the pLPI-untreated NA-eyes, no baseline factors were correlated significantly with the time course of the CECD, and its decline rate - 4.7 (95% Confidence interval (I: - 13.3 to 4.0) cells/mm was not significant (p = 0.267). In the pLPI-treated NA-eyes, the CECD declined with marginal significance - 12.2 (- 24.7 to 0.3) cells/mm/year (p = 0.0513) over 5 years. Higher laser energy used, thicker iris, and shallower central anterior chamber depth (cACD) at baseline were significantly negatively correlated with the post-laser CECD (p = 0.0092, 0.0119, and 0.0158). No significant difference was seen in the baseline factors-adjusted CECD decline rate (p = 0.262) between both the groups.

Conclusion: Prophylactic sequential argon-Nd:YAG pLPI had no clinically significant effects on the time course of the CECD over 5 years in Japanese NA eyes. However, higher laser energy used, thicker iris, and shallower cACD significantly negatively affected the post-laser CECD.