Influence of Nd:YAG laser capsulotomy on toric intraocular lens rotation and change in cylinder power.

ABSTRACT

PURPOSE: To investigate toric monofocal intraocular lens (TIOL) rotation and associated changes in cylinder power caused by NdYAG laser capsulotomy performed due to posterior capsule opacification (PCO). SETTING: Ekol Eye Hospital, Izmir, Turkey. DESIGN: Prospective case series. METHODS: 41 eyes of 20 women and 21 men were included in the study. Before and 1 month after NdYAG laser capsulotomy, TIOL tilt and decentration were determined with Scheimpflug camera, and TIOL axial rotation and the change in cylinder power induced by this rotation were measured by ray tracing aberrometry. The time interval between cataract surgery and NdYAG laser capsulotomy was noted. RESULTS: Rotational misalignment of the TIOL was measured as 4.65 ± 2.75 degrees (range 0 to 11 degrees) before vs 6.97 ± 2.92 degrees (range 0 to 13 degrees) after capsulotomy, and absolute rotation was 2.75 ± 1.94 degrees (range 0 to 7 degrees, P = .028). Before and after NdYAG laser capsulotomy, cylinder power was 0.24 ± 0.70 diopter (D) (range 0.00 to 0.63 D) vs 0.56 ± 0.77 D (range 0.02 to 0.91 D), respectively, with an absolute change in cylinder power of 0.34 ± 0.22 D (range 0.01 to 0.90 D, P = .001). After capsulotomy, there was a significant decrease in IOL tilt in the horizontal and vertical planes and an increase in decentration ( P < .05). Time interval (33.02 ± 12.9 months) and IOL horizontal decentration were independent factors affecting IOL rotation after capsulotomy ( P < .05). CONCLUSIONS: NdYAG laser capsulotomy may cause TIOL rotation as well as tilt and decentration, resulting in a change in the TIOL's corrective effect on corneal astigmatism. Although this change was clinically insignificant, it may be beneficial to consider that TIOL rotational misalignment may occur in patients undergoing early capsulotomy.