Agreement Between Pentacam and IOLMaster in Patients Undergoing Toric IOL Implantation

Journal of refractive surgery (Thorofare, N.J.: 1995) (Impact Factor: 3.47). 02/2013; 29(2):114-20. DOI: 10.3928/1081597X-20130117-06
Source: PubMed


To investigate inter-device agreement between the Pentacam (Optikgerate GmbH, Wetzlar, Germany) and IOLMaster (Carl Zeiss Meditec, Jena, Germany) in measuring corneal power, cylinder, and axis of astigmatism.
Retrospective case series reviewing the status of eyes after toric IOL implantation to evaluate inter-device agreement in measuring corneal power, cylinder, and axis of astigmatism.
Forty-nine eyes from 41 patients were evaluated. Agreement for corneal power and cylinder were deemed good and moderate, with 95% limits of agreement of -1.02 to +1.13 and -1.37 to +1.09 diopters (D), respectively. Agreement for axis of astigmatism was only fair, with a mean absolute difference of 8.9 degrees (range: 0.3 to 37.7 degrees, standard deviation: 8.79 degrees). Thirty percent of eyes had a 10-degree or greater difference in axis measurements, and 13% of eyes had a 20-degree or greater difference in measurements. Analysis by multivariate logistic regression showed higher cylinder powers associated with discrepant corneal power measurements (odds ratio: 3.46, P = .02), and increasing age was associated with discrepant axis measurements (odds ratio: 1.09, P = .03). Overall, there was no significant difference in accuracy predicting postoperative spherical equivalent refraction.
Pentacam and IOLMaster agree well for corneal power but less so for cylinder and axis of astigmatism and thus cannot be used interchangeably.

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