Statistical Analysis Of Anterior And Posterior Segment Biometry In Myopic Eyes: Implications For Icl Sizing
Published 2025 - 43rd Congress of the ESCRS
Reference: PP03.07 | Type: Free paper | DOI: 10.82333/grpm-3e96
Authors: Klaudia Birner* 1 , Markus Schranz 1 , Marcus Lisy 1 , Victor Danzinger 1 , Daniel Schartmüller 1 , Claudette Abela-Formanek 1
1Ophthalmology and Optometry,Medical University Vienna,Vienna,Austria
Purpose
To report the population statistics of 6 anterior segment biometry measurements: white-to-white horizontal diameter (WTW), anterior chamber width (ACW), angle-to-angle horizontal diameter (ATA), sulcus-to-sulcus diameter (STS), ciliary body inner diameter (CBID), and sulcus-to-sulcus lens rise (STSL), and determine the statistical relationship between anterior segment and posterior segment measurements in a large population of myopic eyes.
Setting
London Vision Clinic, London, UK
Methods
Retrospective analysis of 518 consecutive eyes of 260 patients undergoing myopic implantable collamer lens (ICL) surgery. Artemis Insight 100 VHF Digital Ultrasound (ArcScan Inc) was used to collect posterior chamber measurements: CBID, STS, STSL, as well as ATA. MS-39 AS-OCT (CSO Italia) was used to collect anterior chamber measurements: WTW, ACW. Descriptive statistics for the population were calculated. Linear regression analysis was performed between each permutation of anterior and posterior segment measurements to determine the residual variance.
Results
The population mean ± standard deviation [95% CI] was 10.83 ± 0.54 mm [9.76, 11.90] for CBID, 12.18 ± 0.51 mm [11.16, 13.20] for STS, 0.55 ± 0.18 mm [0.19, 0.92] for STSL, 12.17 ± 0.41 mm [11.34, 12.99] for WTW, and 12.17 ± 0.50 mm [11.18, 13.16] for ACW, and 12.23 ± 0.49 mm [11.24, 13.21] for ATA. Linear regression analysis found a weak statistical correlation between anterior and posterior segment measurements, with an R2 of 0.30 for WTW/STS, 0.18 for WTW/CBID, 0.39 for ACW/STS, 0.26 for ACW/CBID, 0.66 for ATA/STS, 0.45 for ATA/CBID.
Conclusions
There was a weak statistical correlation between the anterior chamber measurements and posterior chamber measurements, suggesting that ultrasound-based sizing formulae, such as Dougherty, Kojima and Reinstein may be more effective than anterior segment-based formulae. Angle-to-angle had the highest correlation with STS and CBID. The population statistics of anterior segment measurements are of interest for clinicians determining suitability in ICL candidates.