Optimizing axial length measurement success in advanced cataract patients through pupil dilation.

Purpose: To evaluate the impact of pharmacologic pupil dilation on axial length (AL) measurement in patients with dense cataracts and previous failed AL measurements carried out without pupil dilation.

Design: Retrospective case series.

Methods: All participants underwent swept-source optical coherence tomography (SS-OCT) biometry. Patients with unsuccessful AL measurements due to dense cataract underwent an additional SS-OCT biometric evaluation after pupil dilation, and the SS-OCT AL measurement was compared to the immersion ultrasound.

Results: The study included 3668 eyes of 3668 patients who underwent SS-OCT between October 2021 and March 2023. Of them, 102 eyes (2.8%) had failed AL measurements because of dense cataract. Eighty-seven of those 102 eyes underwent a repeat SS-OCT biometric exam following pharmacologic pupil dilation, after which AL measurements were successfully achieved in 27 (31.0%) of the 87 eyes. These measurements were found to be consistent with immersion ultrasound, supporting the validity of SS-OCT biometer measurements post dilation.

Conclusions: Pharmacologic pupil dilation improved the rate of successful SS-OCT biometrically measured AL in patients with failed AL measurement due to dense cataract.