Photorefractive keratectomy for myopia with -8.00 diopter cylindrical correction.

Purpose: A colleague requested PRK. The last time the patient was seen, no spectacles or contact lenses were worn. However, subjective refraction was -7.00 -5.50 x 165 degrees. The original Nidek nomogram would have suggested setting the laser at the actual refraction. Our algorithm adjustments suggested a 40% extra correction of cylinder would be required. The laser was therefore set to -3.50 -8.00 x 165 degrees aiming for a -1.00 -2.00 x 165 degrees outcome to allow for possible retreatment.

Methods: A 165 micron depth ablation was performed.

Results And Conclusion: At 6 weeks after surgery, visual acuity was 0.63 unaided with a refraction of +1.50 -1.75 x 170 degrees on pred forte.