Corneal astigmatism
Irregular corneal curvature causing distorted vision, requiring correction during refractive or cataract surgery.
Full Definition
Corneal astigmatism results from an asymmetric corneal shape, typically with steeper and flatter meridians creating two focal points rather than one. This refractive error significantly impacts surgical planning for both cataract extraction and refractive procedures. Measurement requires corneal topography or keratometry to determine the magnitude and axis of astigmatism. Correction options include toric IOLs, limbal relaxing incisions, or arcuate keratotomy. Surgical documentation must record preoperative astigmatic measurements, correction method employed, and postoperative refractive outcomes to assess surgical success.
Usage
Usage note: Always document both magnitude and axis when recording corneal astigmatism measurements.
In Context
- "Preoperative corneal astigmatism of 2.75 diopters at 85 degrees was corrected with toric IOL implantation." — Refractive surgery planning
- "Residual corneal astigmatism following surgery required additional limbal relaxing incisions." — Postoperative enhancement procedure