IOLMaster versus Manual Keratometry after Photorefractive Keratectomy

Area of Science:

• Ophthalmology
• Refractive Surgery
• Ophthalmic Instrumentation

Background:

• Accurate keratometric measurements are crucial for refractive surgery outcomes.
• Photorefractive keratectomy (PRK) alters corneal curvature, necessitating reliable postoperative measurements.
• Comparing different keratometry devices is essential for clinical practice.

Purpose of the Study:

• To compare keratometric measurements obtained by the IOLMaster and a Javal type manual keratometer.
• To evaluate these measurements in eyes that have undergone photorefractive keratectomy (PRK) for myopia.

Main Methods:

• A comparative case series involving patients aged 21-27 years undergoing myopic PRK.
• Preoperative and three-month postoperative keratometry performed using both Javal manual keratometer and IOLMaster.
• Postoperative measurements compared against the clinical history method (CHM).

Main Results:

• Seventy eyes of 35 patients were analyzed, with a mean preoperative spherical equivalent of -4.53 D.
• Postoperative mean measurements: IOLMaster 38.03 D, manual keratometry 43.15 D.
• 95% limits of agreement with CHM: IOLMaster (-5.95 to -0.85), manual keratometry (-1.44 to 4.04).

Conclusions:

• IOLMaster and Javal manual keratometer measurements are comparable to each other after PRK.
• Both devices demonstrate significant deviation from CHM measurements.
• Postoperative keratometry from these devices may yield misleading results.