Automatic detection of posterior subcapsular cataract opacity for cataract screening

Cataract is the leading cause of blindness and posterior subcapsular cataract (PSC) leads to significant visual impairment. An automatic approach for detecting PSC opacity in retro-illumination images is investigated. The features employed include intensity, edge, size and spatial location. The system was tested using 441 images. The automatic detection was compared with the human expert. The sensitivity and specificity are 82.6% and 80% respectively. The preliminary research indicates it is feasible to apply automatic detection in the clinical screening of PSC in the future.