Repeatability in Measurements of Two ssOCT and One OLCR Biometer

Evaluation of Repeatability in Measurements of Two Swept-source Optical Coherence Tomography (Ss-OCT) Biometers and One Optical Low Coherence Reflectometry (OLCR) Biometer

Achieving high accuracy and precision in ocular biometry has become primordial for cataract surgery, due to the shift of cataract surgery from a rehabilitation procedure to a refractive one. Aim of this study is to determine the repeatability of ocular biometric parameters obtained using three biometry devices, two ss-OCT biometers and an OLCR device.

Accurate and repeatable biometric measurements are essential in providing an optimal refractive outcome. ss-OCT biometry uses a tunable wavelength laser source to scan the eye, this technology showing its superiority through better signal-to-noise ratio, the wavelength light source being projected into the eye, one at a time; thus improving tissue penetration. This a prospective observational study that would include patients which attended pre-surgical examination. A written informed consent will be obtained from each patient. Only one eye from each patient will be included in the study. All patients included in the study will undergo biometric measurements in a random fashion with the three devices (IOLMaster 700, Lenstar LS 700 and Anterion Heildelberg). Each patient will be measured three times with each device and between the measurements they will be asked to blink or keep their eyes closed for tear film recovery and to avoid fatigue. Scans that pass the quality requirement of each device will be taken for analysis.

Repeatability coefficient (within subject standard deviation - SD) and coefficient of variation between two ss-OCT and the OLCR biometry device will be calculated for all the parameters (axial length, keratometry, anterior chamber depth, lens thickness)

Inclusion Criteria: 40 years old or above age-related cataract Exclusion Criteria: patients with dense cataract or corneal pathology that would significantly influence biometric measurements nystagmus or pathologies that would affect patient fixation pregnancy- for women in reproductive age a pregnancy test will be performed.

Fisus AD, Hirnschall ND, Ruiss M, Pilwachs C, Georgiev S, Findl O. Repeatability of 2 swept-source OCT biometers and 1 optical low-coherence reflectometry biometer. J Cataract Refract Surg. 2021 Oct 1;47(10):1302-1307. doi: 10.1097/j.jcrs.0000000000000633. Erratum In: J Cataract Refract Surg. 2022 Jun 1;48(6):750.