Comparability and intra-/interobserver reliability of anterior chamber depth measurements with the Pentacam and IOLMaster

PURPOSE: To assess the comparability and intra-/interobsever reliability of central anterior chamber depth measurements obtained using the Pentacam and IOLMaster. METHODS: Anterior chamber depth was measured in 50 eyes (25 healthy volunteers)-three times on each eye by two independent observers with each method. A total of 12 measurements were performed on each eye. Analysis of variance was used to analyze the data. Mean values, standard deviations, and confidence limits (95% confidence interval) of the two modalities, two observers, and every observer/modality interaction were calculated. RESULTS: The mean anterior chamber depth values were 3.23 +/- 0.031 mm for the IOLMaster and 3.21 +/- 0.033 mm for the Pentacam. No statistically significant difference was noted in measurements between the two modalities (P=.291) or between the two observers (P=.903). Observer/modality interaction was not significant (P=.643). The confidence limits for observer 1 were 3.223 +/- 0.03 mm and 3.226 +/- 0.03 mm for observer 2. The confidence limits were: observer 1/IOLMaster, 3.23 +/- 0.04 mm; observer 2/IOLMaster, 3.24 +/- 0.04 mm; observer 1/Pentacam, 3.21 +/- 0.04 mm; and observer 2/Pentacam, 3,20 +/- 0.04 mm. The differences in measurements ranged from -0.14 to +0.10 mm for the IOLMaster and from -0.08 to +0.12 mm for the Pentacam The worst deviation from the average eye reading of 3.23 mm was only 0.14 (4.3%). CONCLUSIONS: Good agreement exists between anterior chamber depth measurements by the IOLMaster and Pentacam in the assessment of normal eyes, and they offer observer-independent results. Therefore, the modalities are interchangeable.