Evaluation of Lens Transparency Changes through Photographed Images during a 13-Month Observation Period

Abstract

Since the development of the anterior eye segment analysis system, several new types of anterior eye segment biometry have been performed. The main aim of this study was to evaluate whether changes in cataractous progression or an increase in lens transparency loss are detectable during a relatively short period of 13 months by measuring the intrapupillary opaque shadow area through retroillumination images or by calculating the light scattering intensity at the deepest cortical layer of the lens through Scheimpflug slit images. Secondly, the relationship between maximally dilated pupil sizes and patients’ ages and that between cases with and without diabetes were studied. Thirty-one eyes (49.2%) of sixty-three cataractous lenses showed more than 5% increase in the opaque shadow area. Forthy-five eyes (60.0%) showed more than a 5% increase in light scattering intensity. 92.5% of diabetic eyes and 92.3% of nondiabetic eyes showed pupil sizes over 6.5 mm after an instillation of mydriat-ica. In our study the applied method guaranteed a high reproducibility; thus is might be possible to detect an increase in cataractous changes and lens transparancy in around 50% of examined subjects in a period as short a 1 year. For the evaluation of cataract progression through a retroillumination image, the recommendable pupil size is ≧ 6.5 mm.