Correction of astigmatism after cataract surgery using the light adjustable lens: a 1-year follow-up pilot study.

PURPOSE: The management of preoperative and residual astigmatism is critical to obtain optimized uncorrected visual acuity. The aim of this study was to determine whether residual astigmatism could be precisely corrected postoperatively using the Light Adjustable Lens (LAL, Calhoun Vision Inc) and to determine the stability of the adjusted refraction. METHODS: Ten eyes of 10 patients with cataract and corneal astigmatism between 1.00 and 2.00 diopters (D) were included. After standard phacoemulsification and implantation of the LAL, adjustment and lock-in procedures were completed. Before adjustment and 2 weeks, 6 months, and 1 year after lock-in, a full ophthalmic examination including uncorrected distance acuity (UDVA) and corrected distance visual acuity (CDVA), autorefraction, and manifest refraction was performed. RESULTS: All surgeries, adjustments, and lock-in procedures were performed with no complications. All eyes achieved ±0.50 D of the targeted cylindrical adjustment. Mean spherical equivalent refraction was 0.03±0.84 D before adjustment and -0.06±0.25 D at final follow-up. The cylinder axis remained the same in 60% of eyes and all eyes were stable within 10° rotation at 12-month follow-up. Seven of 10 eyes achieved UDVA of 20/25 or better whereas all eyes achieved UDVA of 20/32 or better. Corrected distance visual acuity remained stable in all eyes. CONCLUSIONS: In this pilot study, the LAL proved to be an efficient, predictable, and stable method of managing astigmatism in cataract patients.

Corneal endothelial safety after ultraviolet light treatment of the light-adjustable intraocular lens.

PURPOSE: To assess the safety to the corneal endothelium of ultraviolet (UV) light treatment to a light-adjustable intraocular lens (IOL). SETTING: Codet Vision Institute, Tijuana, Mexico. DESIGN: Cohort study. METHODS: The study evaluated consecutive patients scheduled for phacoemulsification cataract surgery with implantation of a light-adjustable IOL. Endothelial cell density (ECD), variation in the size of endothelial cells, and the percentage of hexagonal cells were determined centrally with a specular microscope preoperatively, 1 week postoperatively (before UV treatment), and 6 months postoperatively. Two adjustments and 2 lock-in procedures were performed with a light-delivery system between 2 weeks and 4 weeks postoperatively. RESULTS: The study enrolled 10 patients. Specular microscopy showed a mean ECD of 2344 cells/mm(2) preoperatively. The mean overall central ECD was 2047 cells/mm(2) 1 week postoperatively and 2130 cells/mm(2) at 6 months, representing an endothelial cell loss of 12.6% and 9.1%, respectively, from preoperative values. There was no statistically significant difference in the coefficient of variation or percentage of hexagonal cells at either postoperative evaluation. CONCLUSIONS: The endothelial cell loss at 6 months correlated well with previous reports of endothelial damage after phacoemulsification with IOL implantation. The light-adjustable IOL irradiation protocol for adjustment and lock-in procedures did not seem to add to the endothelial damage caused by the cataract surgery, indicating the protocol is safe to the corneal endothelium.