Pre-existing astigmatism can be corrected using LRIs and toric IOLs for patients who undergo cataract surgery.
San Diego-Pre-existing astigmatism can be corrected using limbal relaxing incisions (LRIs) and toric IOLs for patients who undergo cataract surgery. The toric IOLs seem to be superior to LRIs because the cornea stabilizes more quickly following surgery.
The investigators reviewed the medical records of 20 patients (40 eyes) (15 men, 5 women; mean age, 75.5 ± 5.6 years) who underwent primary cataract surgery for bilateral cataracts. All patients had more than 1 D of regular corneal astigmatism. All surgeries were performed at the Fukuyama Eye Clinic, Fukuoka, Japan, from August 2009 to August 2010.
Patients underwent implantation of an AcrySof IQ Toric aspheric IOL (Alcon Laboratories) in one eye (group A, 20 eyes) and implantation of an AcrySof IQ aspheric IOL (Alcon Laboratories) in the fellow eye (group B, 20 eyes) with LRIs. Phacoemulsification and IOL implantation were performed through a 2.4-mm clear corneal incision.
In group A, the incision was placed in the steepest axis. In group B, an incision was placed in the flattest axis and a pair of LRIs in the steepest axis. All patients underwent follow-up examinations at 1 and 2 weeks and 1, 3, and 6 months postoperatively.
Dr. Fukuyama said that the mean keratometric cylinder preoperatively was 1.89 D in group A and 1.73 D in group B, hardly a significant difference. At 1, 3, and 6 months postoperatively, the keratometric cylinder had remained unchanged in group A at 1.89 D but had decreased to 0.81 D in group B; the difference between them was significant (p < 0.02). The mean refractive cylinder was 0.73 D in group A and 0.51 D in group B, which was also significant (p = 0.0034).
The uncorrected distance visual acuity and the corrected distance visual acuity were similar in both groups. The corneal shape measured by topography became stabilized earlier in group A than in group B.