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Rotating the Intraocular Lens to Prevent Posterior Capsular Opacification in Cataract Surgeries
Published on: July 7, 2023
Surgical correction of postoperative astigmatism
1Department of Ophthalmology, University of Minnesota, Minneapolis 55455.
Cornea
|January 1, 1988
Summary
Photokeratoscopy enhances understanding of corneal topography and surgical astigmatic correction. Various surgical techniques, including relaxing incisions and wedge resection, offer predictable astigmatism correction with specific limitations.
Area of Science:
- Ophthalmology
- Corneal Surgery
- Refractive Surgery
Background:
- The photokeratoscope has advanced understanding of corneal topography and the cornea's aspheric nature.
- This knowledge has driven the development of more predictable surgical astigmatic correction models.
Purpose of the Study:
- To review current surgical techniques for astigmatic correction.
- To discuss the efficacy and limitations of various astigmatic correction procedures.
Main Methods:
- Review of surgical techniques including relaxing incisions, wedge resection, and trapezoidal astigmatic keratotomy.
- Discussion of the role of the photokeratoscope and surgical keratometer in astigmatism management.
Main Results:
- Relaxing incisions offer predictable correction by flattening the steeper meridian without significantly altering the spherical equivalent.
- Wedge resection effectively corrects high degrees of postkeratoplasty astigmatism, with 0.10 mm tissue resection yielding approximately 2 diopters of correction.
- Trapezoidal astigmatic keratotomy, a combination of transverse and semiradial incisions, can correct significant astigmatism (5.5-11.0 diopters) based on patient age.
Conclusions:
- Surgical techniques like relaxing incisions and wedge resection provide valuable options for astigmatic correction, though predictability and rehabilitation remain considerations.
- The photokeratoscope and surgical keratometer are crucial tools for assessing corneal topography and guiding surgical endpoints for optimal astigmatism correction.
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