Lenstar LS900 vs EchoScan US-800: comparison between optical and ultrasound biometry with and without contact lenses and its relationship with other biometric parameters

Biometry is a critical aspect of ophthalmology, since it facilitates the measurement of several ocular parameters and aids in the diagnosis of conditions like glaucoma. The advent of the IOLMaster in 1999 marked a pivotal moment in biometry by introducing non-contact and highly precise measurements that revolutionized the field. Low-coherence optical reflectometry devices such as Lenstar LS900 and Aladdin have further advanced biometry, due to the exceptional accuracy they offer. Axial length, a fundamental measurement in biometry, directly correlates with conditions like myopia and glaucoma. The accurate measurement of axial length is crucial for diagnosis and treatment planning. Biometry also guides intraocular lens power calculation during cataract surgery, relying on factors like axial length, anterior chamber depth, lens thickness, and effective lens position (ELP). Ensuring precision in these measurements is essential for optimal surgical outcomes. While several studies have explored biometric parameters, dynamic changes in crystalline lens thickness during rest or accommodation have received little attention. These changes may have a significant effect on the measurement of the anterior chamber length, and consequently impact the overall biometric assessment. This study delves into dynamic biometry, particularly in the context of age-related presbyopia, and aims to assess the feasibility of incorporating into the biometric process a specialized device capable of accurately considering crystalline lens changes during different states like rest and accommodation. This exploration seeks to enhance the understanding of ocular dynamics and contribute to improving the precision of diagnostic and surgical techniques. It underscores the importance of staying at the forefront of biometric research, especially in the context of emerging technologies and their potential to transform ophthalmology.

Section: Introductionmentioning

confidence: 70%

Variations in Lens Thickness Affecting the Anterior Chamber Length and Their Potential Measurement Using a Biometer

Povedano-Montero,

Bernardez-Villaboa,

Martínez-Florentín

et al. 2023

“…Previous analyses have shown good agreement on ACD and CCT measurements between the Lenstar and the Anterion (Heidelberg, Germany), IOLMaster700 (Carl Zeiss, Oberkochen, Germany), OA-2000 (Tomey, Nagoya, Japan), AL-Scan (Nidek Co., Ltd., Tokyo, Japan) and Pentacam AXL (Oculus, Wetzlar, Germany) in healthy, cataractous post-operative eyes and even subjects who have undergone evaluation for cataract surgery [16,19,26,39,49]. On the other hand, studies have also reported differences in ACD and CCT measurements between Lenstar and OA-2000, Pentacam AXL, IOLMaster, IOLMaster700, AL-Scan, Visante AS-OC (Carl Zeiss Meditec, Dublin, CA, USA) and Revo (Optopol Technology, Zawiercie, Poland) in healthy eyes or subjects who have undergone evaluation for cataract surgery [16][17][18][19][20]25,26,39,40,49].…”

Section: Discussionmentioning

confidence: 99%

“…A Lenstar LS900 (Haag-Streit, Köniz, Switzerland), based on optical low-coherence reflectometry, was used to obtain the CCT and ACD values [16,[39][40][41]. In all measurements, the instrument was set automatically; once the operator started the measurement, the device automatically averaged three consecutive measurements.…”

Section: Lenstar Ls900 Ocular Biometermentioning

confidence: 99%

See 1 more Smart Citation

Agreement on Anterior Chamber Depth Measurement between Three Commercially Available Devices

Noya-Padin,

Pena-Verdeal,

Garcia-Queiruga

et al. 2024

Self Cite

The present study aimed to assess the agreement of three commercially available devices on the measurement of anterior chamber depth (ACD) with and without compensation by central corneal thickness measurement (CCT). Fifty eyes were included in an observational cross-sectional study. Participants underwent a single visit during which devices were used to obtain the inclusion/exclusion (ARK510A, Canon TX-10) and studied (VX-120, Lenstar LS900 and EchoScan US-800) parameters. Based on invasiveness, tests were always performed in the same order by one researcher (to avoid inter-observer variability) and only in the right eye (to avoid overstating the precision of estimates) in each participant. The keratometry, autorefraction, intraocular pressure and anterior chamber angle values were used as inclusion criteria, while the CCT and ACD values were used in the agreement analysis between devices. There was a general and a paired difference in ACD measurements between devices (Greenhouse–Geisser: p ≤ 0.001; Sidak: all p ≤ 0.001). No significant difference was found in ACD measurements compensated by CCT values between the devices (Greenhouse–Geisser: p = 0.200). Pairwise analysis showed a significant difference in VX-120 vs. Lenstar (Sidak: p = 0.021). The differences in ACD measurements compensated by CCT values between the devices were clinically acceptable. Consequently, using these instruments interchangeably in daily routines based on this correction is justified.

A Mathematical Model for Axial Length Estimation in a Myopic Pediatric Population Based on Easily Obtainable Variables

Noya-Padin,

Nores-Palmas,

Castro-Giraldez

et al. 2024

Determining the axial length (AL) of the eye is of significant interest in the management of myopia. However, the devices that allow this value to be obtained are either expensive, for example, optical biometers, or inconvenient for use in pediatric population, such is the case with ultrasound biometers. Therefore, this study aimed to develop a mathematical model for estimating the AL value based on easily obtainable variables, with the novel addition of body height to the analysis. A total of 170 eyes of 85 myopic volunteers (mean age of 10.8 ± 1.45 years, ranging from 7 to 14 years) were included in the analysis. Participants underwent anamnesis, keratometry by NVISION-K 5001, subjective refraction by an optometrist, AL measurement by the Topcon MYAH biometer, and body height measurement. Spearman’s correlation test was employed to analyze the relationships between AL and keratometry, spherical equivalent, body height (Sperman’s correlation, all r ≥ 0.267, all p < 0.001), and age (Spearman’s correlation, p = 0.081). Subsequently, multiple regression analysis was conducted on the variables that demonstrated a previous correlation. The mathematical model obtained permits the estimation of AL based on average keratometry, spherical equivalent, and body height. This model is significant (p < 0.001) and explains 82.4% of AL variability.