Reliability of the IOLMaster in measuring corneal power changes after photorefractive keratectomy.
OBJECTIVE
To test the accuracy of the IOLMaster (Carl Zeiss) in detecting corneal power changes after photorefractive keratectomy (PRK).


METHODS
Department of Ophthalmology, 2nd University of Naples, Naples, Italy.


METHODS
Two hundred twenty-five consecutive eyes that had PRK (mean -5.13 diopters [D] +/- 2.98 [SD] [range +0.25 to -16.25 D]) were analyzed. The data included preoperative and postoperative (1, 3, and 6 months) subjective refraction and computerized keratometry. Statistical analysis was performed to determine the correlation between the changes in the subjective refraction at the corneal plane and the changes in keratometry.


RESULTS
The mean difference between the changes in refraction and the measured corneal changes was 0.75 +/- 1.13 D (range -3.84 to +7.68 D) at 1 month, 0.92 +/- 1.10 D (range -0.87 to +7.93 D) at 3 months, and 0.75 +/- 0.98 D (range -1.70 to +3.85 D) at 6 months. The difference was significant (P<.001).


CONCLUSIONS
Automated keratometry provided by the IOLMaster did not accurately reflect the effective refractive changes after PRK, particularly in eyes that had a high dioptric treatment.
Rosa
Nicola
N
Department of Ophthalmology, 2nd University of Naples, Naples, Italy. nicola.rosa@unina2.it
Capasso
Luigi
L
Lanza
Michele
M
Furgiuele
Dario
D
Romano
Antonio
A
D000328:Adult; D001251:Astigmatism / Q000503:physiopathology* / Q000601:surgery; D003315:Cornea / Q000503:physiopathology* / Q000601:surgery; D005260:Female; D006801:Humans; D007368:Interferometry / Q000295:instrumentation / Q000379:methods; D054018:Lasers, Excimer; D008027:Light; D008297:Male; D008875:Middle Aged; D009216:Myopia / Q000503:physiopathology* / Q000601:surgery; D018903:Photorefractive Keratectomy; D012029:Refraction, Ocular / Q000502:physiology; D015203:Reproducibility of Results; D014792:Visual Acuity / Q000502:physiology