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Severe hyperopic shift and irregular astigmatism after radial keratotomy
Tatsuya Mimura1, Shigeto Fujimura, Satoru Yamagami
1Department of Ophthalmology, University of Tokyo Graduate School of Medicine, Japan. mimurat-tky@umin.ac.jp
Eye & Contact Lens
|October 9, 2009
Summary
Radial keratotomy, a refractive surgery, can rarely cause severe hyperopic shift and irregular astigmatism. Wavefront analysis confirmed significant corneal aberrations in a patient experiencing vision loss post-procedure.
Area of Science:
- Ophthalmology
- Refractive Surgery
- Corneal Aberrometry
Background:
- Radial keratotomy (RK) is a surgical procedure to correct myopia.
- RK involves incisions to flatten the cornea.
- Long-term complications of RK can include refractive instability.
Observation:
- A 45-year-old male presented with acute high hyperopia and irregular astigmatism in the left eye 15 years after bilateral RK.
- Best-corrected visual acuity was significantly reduced in the affected eye.
- Corneal topography revealed marked flattening and distorted simulated retinal images.
Findings:
- Wavefront analysis using a Hartmann-Shack aberrometer demonstrated severe irregular astigmatism.
- The patient exhibited a significant hyperopic shift in the left eye (+9.5D).
- Small clear zones were identified amidst the corneal aberrations.
Implications:
- This case highlights a rare but severe complication of radial keratotomy.
- Corneal wavefront analysis is crucial for diagnosing and characterizing complex refractive errors post-RK.
- Understanding these aberrations is vital for managing patients with visual disturbances after refractive surgery.
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