Healio
Healio
March 28, 2016
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Minimal regression seen after intrastromal astigmatic keratotomy

Femtosecond laser-assisted cataract surgery with and without non-penetrating femtosecond laser intrastromal astigmatic keratotomy both yielded “small but statistically significant” regressions in surgically induced astigmatism over time, according to a study.

The prospective study included 263 eyes that underwent femtosecond laser-assisted cataract surgery; 87 eyes underwent concurrent intrastromal astigmatic keratotomy (ISAK) and a comparator group of 176 eyes did not.

Comparing the magnitudes of individual surgically induced astigmatism (SIA) vectors at 1 month and 6 months postoperatively, there was a 0.09 D regression in cylinder in the ISAK group (P = .009), which although statistically significant was not clinically significant, according to the report. Mean SIA regressed significantly in the control group, from 0.43 D at 1 month to 0.32 D at 6 months (P < .001).

Mean preoperative keratometric cylinder was 0.65 D in the ISAK group and 1.23 D in the non-ISAK group.

Keratometric measurements were made with Topcon KR8100PA topographer-autorefractor (Topcon Corporation). The Catalys Precision Laser System was used to perform all surgeries and the Whitestar Signature system (both Abbott Medical Optics) was used to perform phacoemulsification.

ISAKs were 8-mm diameter paired limbal-centered symmetric arcs. Arc lengths ranged from 30° to 90°, according to the study.

The Alpins method was used to perform astigmatic analyses and calculate SIA.

Accounting for magnitude and angular direction of SIA in the ISAK group, the mean change in SIA from 1 month to 6 months was 0.08 D at 94°. Accounting for magnitude and angular direction of SIA in the non-ISAK group, the mean change in SIA from 1 month to 6 months was 0.14 D at 88°. No significant difference in SIA regression was seen between the two groups. – by Matt Hasson

Disclosure: Day reports no financial or proprietary interest in the materials presented herein. Stevens was previously a consultant to Optimedica, manufacturer of the Catalys femtosecond laser, which is now part of Abbott Medical Optics.

Sources/Disclosures

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Source:

Day AC, et al. J Refract Surg. 2016;doi:10.3928/1081597X-20160204-01.