Objective assessment of nuclear cataract: comparison of double-pass and Scheimpflug systems.

Purpose: To compare the objective assessment of lens density by 2 systems (double-pass Optical Quality Analysis System and Pentacam Scheimpflug) in eyes with age-related nuclear cataract.

Setting: Department of Ophthalmology and Visual Science, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, South Korea.

Design: Cross-sectional study.

Methods: In eyes with age-related nuclear cataract, the objective lens density (0 to 100 points) was determined using the Scheimpflug system while subjective grading was achieved using the Lens Opacities Classification System III (LOCS III). The objective scatter index (OSI) (0 to 25) was assessed using the double-pass system.

Results: This study enrolled 47 patients (70 eyes). The mean OSI was 4.08 ± 2.22 (SD), and the mean Scheimpflug-measured lens density was 16.44 ± 4.36; the 2 parameters were correlated (r = 0.764, P<.01). There was a positive linear correlation between the OSI and LOCS III grading scores for nuclear opalescence and nuclear color (r = 0.772 and r = 0.752, respectively; P<.01). The cumulated dissipated energy (CDE) was strongly correlated with the OSI (r = 0.768) and Scheimpflug-measured lens density (r = 0.753).

Conclusions: The OSI based on the double-pass system was correlated with the Scheimpflug-measured lens density, subjective lens grading, and CDE. The OSI may improve the preoperative evaluation of nuclear cataract and help predict phacodynamics in cataract surgery.