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Updated: Jun 4, 2026
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Rotating the Intraocular Lens to Prevent Posterior Capsular Opacification in Cataract Surgeries
Published on: July 7, 2023
Toric intraocular lens misalignment inducing astigmatism after refractive surgery
Adriana S Forseto1, Ricardo M Nosé, Walton Nosé
1Eye Clinic Day Hospital, Metropolitan University of Santos, Sao Paulo, Brazil. forseto@uol.com.br
Journal of Refractive Surgery (Thorofare, N.J. : 1995)
|February 18, 2011
Summary
Unexpected astigmatism occurred after cataract surgery with toric lens implantation in a patient with prior corneal refractive surgery. Careful corneal topography analysis is crucial for accurate toric intraocular lens alignment.
Area of Science:
- Ophthalmology
- Refractive Surgery
- Corneal Surgery
Background:
- Cataract surgery with toric intraocular lens (IOL) implantation is a common procedure to correct refractive errors.
- Previous corneal refractive surgery can alter corneal topography, potentially complicating IOL calculations and alignment.
Observation:
- A 46-year-old male with bilateral cataracts and prior photorefractive keratectomy (PRK) underwent phacoemulsification and toric IOL implantation.
- The operated eye developed unexpected astigmatism despite apparent proper IOL alignment based on preoperative simulated keratometry (K) values.
Findings:
- Retrospective analysis revealed a mismatch in the steepest corneal meridian, causing an off-axis IOL.
- Secondary rotation of the toric IOL successfully improved uncorrected and corrected distance visual acuity.
Implications:
- Accurate assessment of corneal topography is essential for toric IOL alignment in patients with a history of corneal refractive surgery.
- This case highlights the importance of qualitative topographic analysis to identify the true steepest corneal meridian and ensure optimal refractive outcomes.
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