Accuracy of axial length measurement using enhanced retina visualisation mode of swept-source optical coherence tomography biometer in dense cataract

Session Details

Session Title: Presented Poster Session: FLACS & Surgical Devices

Venue: Poster Village: Pod 1

First Author: : A.Tamaoki JAPAN

Co Author(s): :    T. Kojima   A. Hasegawa   M. Yamamoto   T. Kaga   K. Tanaka   K. Ichikawa        

Abstract Details

Purpose:

In cases of dense cataract, it is challenging to measure axial length (AL) with an optical biometer due to scattering of light and attenuation of the light intensity reaching the retina. The enhanced retina visualization (ERV) mode is a unique function to the swept-source optical coherence tomography（SS-OCT）biometer ARGOS (Movu/Santec, Komaki, Japan ). The proprietary data showed that the sensitivity at the retinal segment using ERV mode was 10 times higher than the standard measurement mode. The purpose of this study is to evaluate the accuracy and efficacy of the ERV mode in cases with dense cataracts.

Setting:

Department of Ophthalmology, Chukyo Hospital, Nagoya, Japan. 389 eyes in 288 patients (male was 178 eyes in 133 patients) with Emery-Little grade 4 or greater cataract density were enrolled in this study. The mean age was 72.7±14.5 years. The measurement range of AL was 21.05 mm to 33.87 mm.

Methods:

We reviewed patients who received cataract surgery from July 2016 to January 2019 retrospectively. Among them, it was 85 eyes that could not be measured both by IOLMaster700 (Carl Zeiss Meditec AG, Jena Germany) and the standard mode with ARGOS. We measured AL with ERV mode for them. In eyes that AL was measured with ERV mode before and after surgery (ERV subgroup), the difference between pre- and postoperative AL was compared to evaluate the accuracy of the ERV mode. A p value less than 5% was considered to be a statistically significant.

Results:

In 69 of the 85 eyes (81.2%), AL was successfully measured using the ERV mode. The pre-operative AL (median of difference : 0.055mm) was longer than postoperative AL in the ERV subgroup (N=40, p=0.004). There was statistically significant correlation between the ALs before and after surgery (rs=0.9891, p<0.0001). In 37 eyes excluding outlier, 83.8% (31 eyes) showed that the AL difference before and after surgery was less than 0.2 mm, and 59.5% (22 eyes) showed less than 0.1 mm. The three eyes of outliers were cases with unstable eye fixation or posterior staphyloma.

Conclusions:

In patients with dense cataracts, such as mature cataracts, AL measurement is difficult using standard mode of SS-OCT biometer. The current study showed that ERV mode was a promising method to measure AL accurately. However, when using ERV mode, it is important to pay attention to the eye fixation during AL measurement in cases with dense cataracts.

Financial Disclosure:

None