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 (pLPIsequential) 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 pLPIsequential 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 pLPIsequential-treated NA-eyes (69 subjects; mean age, 68.9 years) and 67 pLPIsequential-untreated NA-eyes (67 subjects; mean age, 64.4 years) were enrolled. In the pLPIsequential-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/mm2 was not significant (p = 0.267). In the pLPIsequential-treated NA-eyes, the CECD declined with marginal significance − 12.2 (− 24.7 to 0.3) cells/mm2/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 pLPIsequential 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.