Estimation of LASIK Flap Thickness

We read with great interest the article by Brenner et al.,1 which compares accuracy of visual estimation of LASIK flap thickness versus ultrasound measurements, and there are some concerns we would like to share. First of all, if the percent of tissue altered (PTA)2 is considered, a customized residual stromal bed should have been estimated for each patient, instead of setting the “safe level” at 300 µm. For instance, for a preoperative 600-µm central corneal thickness (CCT) cornea, a 300-µm residual stromal bed means that the PTA is 50%, clearly beyond the safe zone. Second, although it has

Source: Journal of Refractive Surgery - February 12, 2018 Category: Opthalmology Authors: Alberto Parafita-Fern ández, MD Source Type: research