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Abstract #13808 Published in IGR 8-2
Evaluation of biometric methods for measuring the anterior chamber depth in the non-contact mode
Meinhardt B; Stachs O; Stave J; Beck R; Guthoff RGraefe's Archive for Clinical and Experimental Ophthalmology 2006; 244: 559-564
PURPOSE: High-resolution biometry of the anterior ocular segment is now becoming more and more important against a background of refractive surgery and the evaluation of potentially accommodative lens replacement materials. The aim of this study was a systematic investigation of the currently available non-contact methods for measuring the anterior chamber depth (ACD). METHODS: The ACDs of 50 phakic eyes of 27 patients aged between 19 and 59 years were measured with the IOL-Master (Zeiss), the AC-Master (Zeiss), the Pentacam (Oculus) and slit-lamp pachymetry by Jaeger (Haag-Streit). RESULTS: The median anterior chamber depth in the investigated eyes was 3.63 mm for the IOL-Master (minimum 2.88 mm, maximum 4.22 mm), 3.802 mm for the AC-Master (2.816 mm-4.373 mm), 3.915 mm for the Pentacam (minimum 2.994 mm, maximum 4.614 mm) and 3.75 mm for Jaeger (2.887 mm-4.29 mm). With a probability of error of α = 0.05 there were no significant differences concerning the ACD between the methods of Jaeger and AC-Master, Jaeger and IOL-Master, or Pentacam and AC-Master (Wilcoxon and Wilcox). The intra-individual variability was ± 5.4 μm for AC-Master, ± 12.7 μm for Pentacam, ±24.5 μm for IOL-Master and ±41.2 μm for Jaeger. The maximum method-dependent difference in ACD determination was 285 mum. CONCLUSIONS: All the methods allow non-contact biometry, but the results might differ due to measuring principles inherent to the system, experience of the examiner and compliance of the patient. Partial coherence interferometry with the AC-Master offers the advantage of measurement exactly along the optical axis with the highest reproducibility and patient compliance.
Dr. B. Meinhardt, Eye Clinic of the University of Rostock, Rostock, Germany
Classification:
6.3.1 Anterior segment (Part of: 6 Clinical examination methods > 6.3 Biomicroscopy (slitlamp))