Objective Quantification of Lens Opacity in Posterior Subcapsular Cataracts Using IOL Master 700 and CASIA-2.

Purpose: To objectively quantify the lens opacity of posterior subcapsular cataracts (PSCs) using the swept-source optical coherence tomography (SS-OCT)-based devices including IOL Master 700 and CASIA-2.

Design: Prospective cross-sectional study.

Methods: A total of 101 eyes of 101 patients with PSCs were enrolled in Zhongshan Ophthalmic Center from 2021 to 2022. The IOL Master 700 and CASIA-2 were used to obtain lens images. The average posterior subcapsular density (APSD) and the maximum posterior subcapsular density (MPSD) within the pupil area (radius: 3 or 5 mm) were measured by Image J. Spearman and Pearson correlation analysis were performed to assess the associations.

Results: APSD-3mm, APSD-5mm, MPSD-3mm, and MPSD-5mm had positive correlations with best corrected visual acuity (BCVA; r = 0.658, 0.641, 0.583, and 0.572, P < .001, respectively), all of which were higher than the correlation between LOCS-III P score and BCVA (r = 0.548, P < .001). Particularly, the APSD-3mm showed the highest correlation with BCVA. APSD could distinguish severe PSCs (LOCS-III P score ≥ 5) with an area under the receiver operating characteristic curve (AUC) of 0.836 (95% CI 0.743-0.930) for APSD-3mm and with AUC 0.758 (95% CI 0.643-0.873) for APSD-5mm, highlighting the better performance of APSD-3mm. The APSD-3mm of IOL Master 700 correlated strongly with that of CASIA-2 (r = 0.789, P < .001).

Conclusions: This study presented an objective method for quantifying PSCs using IOL Master 700 and CASIA-2. APSD-3mm can be used as a new accurate and objective index for the quantitative assessment of PSCs.