Phacoemulsification with different sizes of clear corneal Incisions in Cataract after Radial Keratotomy

Abstract

Objective: To evaluate the clinical effect of phacoemulsification with different sizes of clear corneal incisions in cataract after radial keratotomy (RK). Methods: This retrospective case series study from January 2011 to August 2015, included 16 cases (26 eyes) of cataract patients with a history of RK more than 10 years. Three cases (6 eyes) had 8 RK incisions, 8 cases (12 eyes) had 12 RK incisions, and 5 cases (8 eyes) had 16 RK incisions. All phacoemulsification and intraocular lens (IOL) implantations were performed through clear corneal incisions made by the same surgeon. For the cases with 8 RK incisions, 4 eyes had a 3.2 mm clear corneal incisions and 2 eyes had a 3.0 mm clear corneal incisions. For the cases with 12 RK incisions, 4 eyes had a 3.2 mm clear corneal incision and 8 eyes had a 2.2 mm clear corneal incisions. For the cases with 16 RK incisions, 5 eyes had a 3.2 mm clear corneal incision and 3 eyes had a 2.0 mm clear corneal incisions. Dehiscence of the RK incisions, management of complications, and postoperative visual acuity recovery were observed 1 day, 1 week, and 1, 3, 6, 12, 24, and 36 months after surgery. The preoperative and postoperative parameters were analyzed by paired t-tests. Results: In the cataract surgery, no RK incisions dehisced in any of the eyes with 8 or 12 RK incisions, and all of the clear corneal incisions closed well. For cataract surgery of 6 eyes following RK with 16 clear corneal incisions, there was also no dehiscence of the RK incisions, but for RK incisions adjacent to the clear corneal incision, two eyes dehisced. The dehiscence of RK incisions was closed by injecting an air bubble into the anterior chamber. The follow-up time (mean±SD) was 12.9±11.6 months. During the follow-up, the incisions closed well in all of the 26 eyes, and no new dehiscence of RK incisions occurred. In the last follow-up, the best corrected visual acuity (BCVA) was 0.19±0.12, which was better than the preoperative BCVA (t=-6.913, P<0.001). The spherical equivalent refraction was -0.43±1.64 diopter (D), which was less than preoperative value (t=-5.983, P<0.001). The corneal astigmatism was 1.92±0.85 D, and there was no difference with preoperative value (t=-0.68, P=0.506). The corneal endothelial cell density was 1 893±826 cells/mm2, which was less than preoperative value (t=4.048, P=0.001). Conclusions: Phacoemulsification and IOL implantation with clear corneal incisions in cataract patients after RK was effective and safe. Better results may be achieved with 3.2 mm or smaller clear corneal incisions in cataract surgery after RK with 8 incisions, 2.2 mm or smaller clear corneal incisions after RK with 12 incisions, and 2.0 mm or smaller clear corneal incisions after RK with 16 incisions. Key words: phacoemulsification; radial keratotomy; intraocular lenses; corneal incisions