Repeatability and reproducibility of a new fully automatic measurement optical low coherence reflectometry biometer and agreement with swept-source optical coherence tomography-based biometer

Correspondence to Dr Jinhai Huang, Eye Institute and Department of Ophthalmology, Institute for Medical and Engineering Innovation, Eye & ENT Hospital, Fudan University; NHC Key Laboratory of Myopia (Fudan University), Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Fudan University, Shanghai, Shanghai, 200031, China; [email protected] ; Dr Xingtao Zhou; [email protected]

WHAT IS ALREADY KNOWN ON THIS TOPIC

• Suoer SW-9000 μm Plus biometer as a new optical low coherence reflectometry device has not been effectively studied, while the measurement accuracy of IOLMaster 700 based on swept-source optical coherence tomography has been proven. It is necessary to explore the precision of SW-9000, and the differences with IOLMaster 700.

WHAT THIS STUDY ADDS

• This is the first study to verify the measurement accuracy of SW-9000 by evaluating its repeatability and reproducibility, as well as its agreement with IOLMaster 700.

HOW THIS STUDY MIGHT AFFECT RESEARCH, PRACTICE OR POLICY

• We confirmed the reliability of SW-9000 in the measurement of axial length, central corneal thickness, aqueous depth, anterior chamber depth, mean keratometry, lens thickness and corneal diameter, which is helpful to the correctness of clinical decision.

Introduction

In recent years, the incidence of myopia has increased worldwide. About half of the global population will be myopic in <30 years.¹ The increased prevalence of myopia will increase the risk of cataract, glaucoma, retinopathy and severe irreversible vision loss.² Previous studies have shown that many ocular parameters are linked to refractive statuses, such as axial length (AL) and corneal curvature (K).³ Therefore, optical biometry has become an indispensable item in the refractive examination. The precise measurements of ocular parameters are crucial to meeting the postoperative expectations of those who have undergone refractive surgery for myopia.⁴

During the last 20 years, optical biometry has progressively replaced ultrasound biometry,^{5 6} which is limited by several drawbacks, such as direct corneal-probe contact and experience-dependence. Recently, optical technologies, such as optical low coherence reflectometry (OLCR) and swept-source optical coherence tomography (SS-OCT), have been successfully applied in clinics and replaced the original partial coherence interferometry.⁷ Previous studies have shown excellent intraoperator repeatability and interoperator reproducibility of OLCR-based and SS-OCT-based devices.^{8 9}

The Suoer SW-9000 μm Plus biometer (Suoer, China) and the Lenstar LS900 (Haag-Streit, Switzerland) use the OLCR technology...