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Published on: September 20, 2024
Linear-long incisions with a small optical zone for the correction of astigmatism in older patients
Hui-Chun Ho1, Ko-Hua Chen, Wen-Ming Hsu
1Department of Ophthalmology, Taipei Veterans General Hospital, Taipei, Taiwan. National Yang-Ming University, Taipei, Taiwan.
Purpose:
To evaluate the efficacy of astigmatic keratotomy (AK) by paired linear (transverse)-long incisions within a small optical zone in older patients with 3.00 diopters (D) or more of astigmatism who are intolerant of contact lenses, spectacles, or both.
Design:
Prospective, noncomparative case series.
Participants:
Twenty-one eyes (20 patients; age range, 58-87 years) treated at clinics of the Taipei Veterans General Hospital were included in this study.
Methods:
Paired linear incisions (90 degrees in length) with a central optical zone (OZ) of 4.5 mm were made to correct high astigmatism in older patients. The incisions were 80% of the corneal thickness and parallel to the axis of the steepest cylinder.
Main Outcome Measures:
Refraction, keratometry, corneal topography, and visual acuity with and without correction were measured as the outcome indicators.
Results:
The mean course of the stabilization of corneal curvature was 1.8 months. Significant improvement from a preoperative corneal astigmatism of 4.52+/-1.39 D to a postoperative value of 1.82+/-0.88 D (P<0.0001) was shown. Marked axis deviations of more than 30 degrees were observed in 5 cases and corneal perforation was observed in 1 case. When the corneal curvature stabilized, uncorrected visual acuity was improved by 2 lines or more in 15 eyes (71.4%). Spherical equivalents and best-corrected visual acuity did not change significantly. Postoperative glare was absent in all patients.
Conclusions:
We conclude that AK by linear-long incisions extending from a small OZ is effective and safe for correcting astigmatism.
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