Risk assessment for ectasia after corneal refractive surgery

Area of Science:

• Ophthalmology
• Corneal Surgery
• Refractive Surgery

Background:

• Excimer laser corneal refractive surgery, including LASIK and PRK, is widely performed.
• Postoperative corneal ectasia is a rare but serious complication.
• Identifying risk factors is crucial for preventing ectasia.

Purpose of the Study:

• To analyze the epidemiology of ectasia after excimer laser corneal refractive surgery.
• To identify risk factors associated with its development.
• To devise an improved screening strategy to minimize ectasia occurrence.

Main Methods:

• Retrospective comparative and case-control study.
• Inclusion of published and unpublished ectasia cases and a control group.
• Evaluation of preoperative, perioperative, and postoperative characteristics.

Main Results:

• 171 ectasia cases identified, predominantly after LASIK (95.9%).
• Significant risk factors included abnormal preoperative topography, younger age, higher myopia, thinner preoperative corneas, and less residual stromal bed (RSB) thickness.
• Abnormal topography was the most significant predictor, followed by RSB thickness, age, and corneal thickness.

Conclusions:

• A quantitative risk stratification scale was developed, demonstrating high specificity (91%) and sensitivity (96%).
• This validated method can significantly improve the identification of eyes at risk for ectasia.
• The findings support enhanced screening strategies for refractive surgery candidates.