ESCRS - PP03.16 - Differences In Key Biometry Measurements Pre-Cataract Surgery Using Lenstar Vs Anterion Biometers.

Differences In Key Biometry Measurements Pre-Cataract Surgery Using Lenstar Vs Anterion Biometers.

Published 2022 - 40th Congress of the ESCRS

Reference: PP03.16 | Type: Free paper | DOI: 10.82333/qefn-jj72

Authors: Magdalena Niestrata* 1 , Ahmed Al-Nahrawy 1 , Ahmad Aziz 2 , Yulia Gad-El 1 , Petra Sousa 1 , Mukhtar Bizrah 1

1Ophthalmology,Imperial College London - Western Eye Hospital, London, UK,London,United Kingdom, 2Imperial College London - Western Eye Hospital, London, UK,London,United Kingdom

Purpose

The aim was to compare biometry readings between Anterion (Heidelberg Engineering) and Lenstar (Haag-Streit) for patients undergoing cataract surgery and to identify any differences and their significance for surgical planning.  

Setting

The study was conducted at Western Eye Hospital, Imperial College NHS Trust, in Outpatient Department. 

Methods

Biometry measurements were performed on patients in Imperial College London NHS Trust between November’21 and February’22, using Lenstar and Anterion. The parameters of axial length (AL), K1, K2 in diopters (D), anterior chamber depth (ACD), lens thickness and white-to-white (WTW) were compared. The mean differences in measurements were evaluated using standard deviation (SD), 95% confidence intervals (CI) and p values. Pseudophakic eyes were excluded from the analysis. Statistical analysis was performed using Python and Excel software.  

Results

In total, 36 patients, 66 eyes, were included. The mean age was 69 (SD 11.1) with 17 (47.22%) males and 19 (52.78%) females. Seven eyes were excluded from AL analysis due to unrecordable measurements with Anterion in dense cataracts. The mean AL difference was 0.00034mm (SD 0.037mm; CI +/- 0.00963) (p=0.47). The mean ACD difference was 0.476mm (SD 0.143mm; CI 0.035) (p=0.03). The mean lens thickness difference was 0.130mm (SD 0.395mm; CI 0.099), statistically very significant (p=0.005). The mean WTW difference was significant with 0.103mm (SD 0.839mm; CI 0.212) (p=0.02). The mean differences in K1 and K2 were small with 0.071D (SD 0.367D; CI +/- 0.090) (p=0.59) and 0.155D (SD 0.444; CI +/- 0.109) (p=0.31), respectively. 

Conclusions

Both Biometers produce similar AL readings. Anterion seemed unable to measure AL in some dense cataracts, which needs further evaluation on a larger cohort. There was a notable difference in ACD, which may be explained by Lenstar reading being taken from the corneal epithelium to lens epithelium vs Anterion one from corneal endothelium to lens epithelium. There was a statistically very significant difference in lens thickness, relevant for surgical planning. There was a relatively large difference in WTW readings, which may be important in anterior chamber intraocular lens selection. Future studies are needed particularly in extremes of AL, to determine any difference in suitability of the different biometers in such circumstances.