Repeatability of an SD-OCT biometer (MS-39 AL) and agreement with a validated biometer (IOLMaster 700).

Purpose

To evaluate the repeatability of biometric measurements obtained with the MS-39 AL (CSO) and to assess their agreement with those provided by the IOLMaster 700 (Carl Zeiss).

Setting

IRCCS Bietti Foundation, Rome, Italy.

Design

Prospective evaluation of diagnostic test.

Methods

Patients were classified in Group A (with cataract) and Group B (with clear lens). For repeatability analysis, three measurements were obtained with the MS-39 AL. Agreement was analyzed by comparing the first MS-39 AL measurement with the corresponding measurement by the IOLMaster 700.

Results

111 eyes were enrolled. Group A included 53 eyes (mean age: 69.4 ±7.3 years) and Group B 58 eyes (mean age 35.5 ±9.1 years). In both groups, the MS-39 AL demonstrated high repeatability for all biometric parameters, as the coefficient of variation ranged from 0.04% for axial length to 2.10% for lens thickness, except in the case of corneal astigmatism. Agreement between biometers was high for most parameters, with narrow 95% limits of agreement. Significant differences were observed for anterior chamber depth (MS-39 AL = 3.52±0.44 mm, IOLMaster 700 = 3.42±0.45 mm, p <0.0001), corneal diameter (MS-39 AL = 11.90±0.46 mm, IOLMaster 700 = 12.19±0.49 mm, p <0.0001), central corneal thickness (MS-39 AL = 531.75±31.20 µm, IOLMaster 700 = 534.80±32.79 µm, p <0.001) and lens thickness (MS-39 AL = 4.18±0.55 mm, IOLMaster 700 = 4.13±0.52 mm, p = 0.002).

Conclusions

The MS-39 AL provides highly repeatable biometric measurements and shows good agreement with the IOLMaster 700 for most parameters in both cataractous and clear-lens eyes.