BIOMETRIC RATIOS OF THE PHAKIC EYE AND THE EFFECT ON IOL POWER CALCULATION

Published 2026 - 30th ESCRS Winter Meeting

Reference: PP02.02 | Type: Presented Poster & Poster | DOI: 10.82333/tcse-3772

Authors: Sophia Anna Reifeltshammer* ¹ , Leon Pomberger ¹ , Haidar Khalil ¹ , Theresa Höftberger ¹ , Matthias Bolz ¹ , Nino Hirnschall ¹

¹Department of Ophthalmology,Kepler University Clinic,Linz,Austria;Department of Ophthalmology,Johannes Kepler University,Linz,Austria

Purpose

To evaluate the biometric ratios of the phakic and to investigate the influence on IOL power calculation

Setting

Department of Ophthalmology, Kepler University Clinic, Linz, Austria
Department of Ophthalmology, Johannes Kepler University, Linz, Austria

Methods

This study included patients undergoing routine clinical assessment. Measurements included optical biometry (IOLMaster700, Carl Zeiss Meditec AG, Germany) and anterior segment optical coherence tomography (AS-OCT) (CASIA2, Tomey, Japan). Biometric data (anterior chamber depth (ACD); axial eye length (AL); central corneal thickness (CCT); lens thickness (LT)) were used to analyze the anatomical relationships (i.e. ratios of biometric parameters). Statistical analysis was performed using SPSS (IBM, USA) and Python (Ver. 3.12.7).

Results

Data from 2499 phakic eyes of 2499 patients were evaluated. An average ratio for CCT/AL of 0.020±0.002, ACD/AL of 0.128±0.015, LT/AL of 0.157±0.016 and vitreous/AL of 0.695±0.022 was found. A significant difference in the ratios of CCT/AL, LD/AL, V/AL between the subgroups of short (<22.00mm), normal (22.00-25.99mm) and long (>26.00mm) eyes as well as an intergenerational shift was observed. There was a significant correlation of AL with ACD (r=0.487; p<0.01); LT (r=-0.264; p<0.01) and age (r=-0.244; p<0.01). Findings regarding the influence on IOL power prediction will be presented at the meeting.

Conclusion

There was an intergenerational and axial length-related shift in anatomical relationships. Not only AL, but also a deviation of the different ratios within the eye could lead to errors in the artificial lens calculation. In the future, precise knowledge of the ratios could be useful when performing IOL power calculation.