A new optical low coherence reflectometry device for ocular biometry in cataract patients

TLDR

Optical low‑coherence reflectometry devices such as Lenstar, Haag‑Streit, and Allegro Biograph provide high‑resolution, non‑contact ocular biometry. The study assesses the validity and repeatability of Lenstar measurements relative to existing clinical instruments. Measurements were obtained with LenStar and IOLMaster in 112 cataract patients (aged 41–96 y) and, for 21 patients, supplemented with A‑scan ultrasonography. LenStar measurements were highly repeatable (≤2 % variability), exhibited minor statistical differences from IOLMaster and ultrasound that were not clinically significant, and failed in a similar proportion of patients due to media opacities.

Abstract

<h3>Background:</h3> A new commercially available optical low coherence reflectometry device (Lenstar, Haag-Streit or Allegro Biograph, Wavelight) provides high-resolution non-contact measurements of ocular biometry. The study evaluates the validity and repeatability of these measurements compared with current clinical instrumentation. <h3>Method:</h3> Measurements were taken with the LenStar and IOLMaster on 112 patients aged 41–96 years listed for cataract surgery. A subgroup of 21 patients also had A-scan applanation ultrasonography (OcuScan) performed. Intersession repeatability of the LenStar measurements was assessed on 32 patients <h3>Results:</h3> LenStar measurements of white-to-white were similar to the IOLMaster (average difference 0.06 (SD 0.03) D; p = 0.305); corneal curvature measurements were similar to the IOLMaster (average difference −0.04 (0.20) D; p = 0.240); anterior chamber depth measurements were significantly longer than the IOLMaster (by 0.10 (0.40) mm) and ultrasound (by 0.32 (0.62) mm; p&lt;0.001); crystalline lens thickness measurements were similar to ultrasound (difference 0.16 (0.83) mm, p = 0.382); axial length measurements were significantly longer than the IOLMaster (by 0.01 (0.02) mm) but shorter than ultrasound (by 0.14 (0.15) mm; p&lt;0.001). The LensStar was unable to take measurements due to dense media opacities in a similar number of patients to the IOLMaster (9–10%). The LenStar biometric measurements were found to be highly repeatable (variability ⩽2% of average value). <h3>Conclusions:</h3> Although there were some statistical differences between ocular biometry measurements between the LenStar and current clinical instruments, they were not clinically significant. LenStar measurements were highly repeatable and the instrument easy to use.