Differences Among Ultrasonic Pachymeters in Measuring Corneal Thickness

Abstract

Corneal thickness measurements were performed on both eyes of six volunteers using eight currently available ultrasonic pachymeters and the prototype of another unit, soon to be released. We found significant differences in the measurements among pachymeters. Variances of 49 microns, centrally; 59 microns, paracentrally; and 146 microns, peripherally were found, Surgeons using these instruments in refractive surgery should be aware Of these differences and be cautious when changing units or using more than one type of unit, to avoid unwanted perforations or shallow incisions.