Aim: To compare anterior chamber depth (ACD) measurement by three non-contact devices, the IOLMaster, Scanning Peripheral Anterior Chamber Depth Analyser (SPAC) and Visante Anterior Segment Optical Coherence Tomography (AS-OCT)
Methods: This was a prospective, cross-sectional study of 497 phakic subjects above the age of 50 attending a community clinic in Singapore. ACD of right eyes in subjects was measured using IOLMaster, SPAC and AS-OCT by the same investigator. The ACD was measured from the corneal epithelium to the anterior lens surface, and ACD measurements were compared using Bland- Altman analysis.
Results: A total of 232 men and 265 women were examined, with a mean age of 63.4 ± 7.9 (SD) years. The mean ACD was 3.08 ± 0.36 mm with IOLMaster, 3.10 ± 0.44 with SPAC and 3.14 ± 0.34 with AS-OCT. A significant difference was noted between the ACD measurements recorded by the three devices (p <0.0001) with AS-OCT measurements being deeper than IOLMaster and SPAC. The mean difference between AS-OCT and IOLMaster measurements was 0.062 ± 0.007 mm (p<0.0001, 95% limits of agreement (LoA): -0.37mm to 0.25mm); between AS-OCT and SPAC was 0.035 ± 0.011 (p=0.0001, 95% LoA: -0.44mm to 0.51mm) and between SPAC and IOLMaster was 0.027 ±0.012 (p=0.027, 95% LoA: -0.57mm to 0.50mm).
Conclusions: AS-OCT measurements of ACD are deeper than those with SPAC and IOLMaster. However, as the differences found were small, they are unlikely to be clinically important.
- angle closure
- anterior chamber depth
- anterior segment
- anterior segment OCT