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Updated: Aug 24, 2026

Correction of Presbyopia by Monocular Bi-Aspheric Ablation Profile
Published on: September 20, 2024
Correction of spherical myopia with a single 150-degree intrastromal corneal ring segment
1W.K. Kellogg Eye Center, Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI 48105, USA. asugar@umich.edu
Abstract:
A 47-year-old woman with an uncorrected visual acuity (UCVA) of 20/70 and a refraction of -1.50 +0.75 x 75 in the right eye had 2 0.25 mm intrastromal corneal ring segments (Intacs) inserted uneventfully through a superior incision. The patient was hyperopic 2 years later with a refraction of +0.50 +0.75 x 25 and was intolerant of spectacles. She also complained of temporal glare. Twenty-seven months after insertion, the temporal ring segment was removed. Four months later, the UCVA was 20/20; with a refraction of plano +0.50 x 35, the visual acuity was 20/15. Topography showed corresponding regular astigmatism, and the patient's glare had resolved. Removal of 1 Intacs segment may be an option in cases of overcorrection after ring insertion for myopia.
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