IntraLase-enabled astigmatic keratotomy for postkeratoplasty astigmatism.

Department of Ophthalmology, Toronto Western Hospital, Donald K. Johnson Eye Center, University Health Network, University of Toronto, Toronto, Ontario, Canada.
American Journal of Ophthalmology (Impact Factor: 4.02). 09/2008; 146(6):897-904.e1. DOI: 10.1016/j.ajo.2008.07.004
Source: PubMed

ABSTRACT To report on the outcomes of IntraLase-enabled astigmatic keratotomy (IEAK) and to compare it with manual astigmatic keratotomy (AK) for the management of postkeratoplasty astigmatism.
Retrospective, comparative case series.
Forty eyes of 39 patients treated at a cornea clinic at the Toronto Western Hospital were included. Twenty eyes underwent manual AK and 20 eyes underwent IEAK. The main outcome measures included preoperative and postoperative manifest refraction, uncorrected and best-corrected visual acuity (UCVA, BCVA), corneal topography, high-order ocular aberrations, and complications.
In the manual AK group, UCVA (logarithm of the minimum angle of resolution) improved from 1.08 +/- 0.29 before surgery to 0.93 +/- 0.45 after surgery (P = .09), and in the IEAK group, UCVA improved from 1.14 +/- 0.42 before surgery to 0.82 +/- 0.44 after the procedure (P = .004). BCVA improved from 0.63 +/- 0.40 to 0.44 +/- 0.38 (manual AK; P = .16) and from 0.52 +/- 0.38 to 0.29 +/- 0.26 (IEAK; P = .01), respectively. Mean cylinder reduction was 3.23 +/- 4.69 diopters in the manual AK group and 4.26 +/- 1.72 diopters in the IEAK group (P = .36). Two eyes in each group lost one line of BCVA. Three patients (15%) in the manual AK group had corneal perforation and required resuturing of the AK wound (P = .23) Overcorrection occurred at a similar rate in the two groups.
Treatment of postkeratoplasty astigmatism with IntraLase is a safe and effective surgical procedure and resulted in a significant improvement in UCVA and BCVA compared with manual AK. A larger sample series is needed to refine further this new technique of AK and to compare it with accepted manual techniques.

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