The influence of size and shape of Nd:YAG capsulotomy on visual acuity and refraction.

Abstract

To evaluate the influence of size and shape of neodymium:yttrium aluminum- Garnet (Nd:YAG) laser capsulotomy on visual acuity and refraction. We retrospectively evaluated 85 eyes of 67 patients treated with Nd:YAG laser posterior capsulotomy for posterior capsule opacification (PCO). The mean age of included patients was 57.57 ± 9.26 (mean ± standard deviation, 38-75 years). The mean interval between surgery and Nd:YAG laser capsulotomy was 26.09 ± 7.08 (10-38) months. Patients were divided into four groups according to the shape and size of capsulotomy. Groups comprised patients with cruciate shape capsulotomies with openings of less than or equal to 3.5 mm (Group 1) or greater (Group 2) and patients with circular shape capsulotomies with openings of less than or equal to 3.5 mm (Group 3) or greater (Group 4). The mean number and energy of laser firings were significantly higher in Group 4 (p=0.00), and significantly lower in Group 1 (p=0.00), compared with that in other groups. Pre-procedural and post-procedural mean spherical equivalent (SE) values were significantly higher in Group 1 (p=0.026 and p=0.011, respectively). No statistical difference in best-corrected visual acuities (BCVA) or intraocular pressures (IOP) were observed between groups before (p=0.44 and p=0.452, respectively) or after capsulotomy (p=0.108 and p=0.125, respectively). A significantly higher number of patients in Group 4 (p=0.001), and a significantly lower number of patients in Group 1 (p=0.001), reported floating bodies compared with that in other groups. No significant changes in SE or intraocular pressure were observed after capsulotomy in any group (p=0.074 and p=0.856, respectively). Best-corrected visual acuity was significantly improved following capsulotomy in all groups (p<0.01). Cruciate shape capsulotomy with an opening of 3.5 mm or less provides the greatest improvement in visual function with minimal complications.