IOLMaster versus Manual Keratometry after Photorefractive Keratectomy

PURPOSE To compare keratometric measurements using a Javal type manual keratometer with IOLMaster in eyes undergoing photorefractive keratectomy (PRK) for myopia. METHODS In this comparative case series, we studied patients aged 21 to 27 years scheduled for myopic PRK. Keratometry was performed preoperatively and three months after the procedure using a Javal type manual keratometer and the IOLMaster. We compared postoperative measurements obtained by both instruments with the clinical history method (CHM). RESULTS Seventy eyes of 35 patients with mean age of 23.45±1.55 years were studied. Mean preoperative spherical equivalent was -4.53±1.3 D. Average preoperative IOLMaster and manual keratometric readings were 45.95±1.23 D and 46.32±1.18 D, respectively. Postoperatively, mean IOLMaster measurements was 38.03±0.68 D and that of manual keratometry was 43.15±1.1 D. Compared to CHM measurements, the 95% limits of agreement were -5.95 to -0.85 for the IOLMaster and -1.44 to 4.04 for manual keratometry. CONCLUSION Keratometric measurements with the IOLMaster and a Javal type manual device are comparable after PRK; both are largely deviant from the CHM and can yield misleading results.