The effect of Neodymium Yttrium Aluminium Garnet laser capsulotomy on intraocular pressure and retinal nerve fibre thickness

Abstract

Purpose To study the effect of Neodymium Yttrium Aluminum Garnet (Nd:YAG) laser capsulotomy on intraocular pressure (IOP) and retinal nerve fibre layer (RNFL) thickness in all patients and diabetic patients with post-cataract posterior capsule opacification (PCO). Design Prospective cohort study Methods In all the patients, including the diabetic patients, the IOP and RNFL were measured and the PCO graded before Nd:YAG laser capsulotomy (baseline), and the IOP measured at 15 minutes, 2 hours, 1 week and 1 month after laser capsulotomy. Additionally, the RNFL was measured at 1 month after laser capsulotomy. The IOP and RNFL at the aforementioned timepoints after laser capsulotomy was compared to the baseline IOP and RNFL in all patients and in diabetic patients. Results Compared to baseline there was a significant increase in IOP of 0.9mmHg at 2 hours (p = 0.01) after laser capsulotomy in all patients. In diabetic patients there was a significant increase in IOP of 1.58mmHg at 15 minutes (p = 0.01) and 1.21mmHg at 2 hours (p = 11 0.006). There was a significant decrease in the RNFL thickness in diabetic patients 1 month after laser capsulotomy (p= 0.009); there was no decrease in RNFL thickness in all the patients at this time point. Conclusion The prolonged (15 minutes to 2 hours) increase in IOP and the decrease RNFL thickness at 1 month in diabetic patients suggest that these patients are at increased risk of glaucoma. Further longitudinal studies are required to determine if diabetic patients develop glaucoma after Nd:YAG laser capsulotomy.