The comparability of estimates of retroilluminated lens opacities as judged from film-based and digital imaging

PURPOSE: Neitz film-based retroillumination cameras, the standard for documenting retroilluminated lens opacities for epidemiologic studies, are no longer produced. A digital imaging system is now available for imaging these opacities. We sought to compare gradings of images from both systems. DESIGN: Comparison of technique. METHODS: One hundred fourteen lenses were imaged with both systems and graded according to protocols. Concordance between the methods was compared using kappa statistics. RESULTS: There was moderate concordance for cortical opacities (kappa = 0.63) and good concordance for posterior subcapsular opacities (kappa = 0.83). Grades from digital images slightly underestimated the frequency and severity of cortical cataract. CONCLUSION: Digital imaging of retroilluminated lens opacities results in similar classification of the severity of opacities. It will be useful for epidemiologic studies of cortical (CC) and posterior subcapsular cataracts (PSC).