Evidence for non-selective colour channel involvement in diabetic eyes especially after laser treatment

Abstract

Purpose: We consider the hypothesis that proliferative diabetes produces selective loss of colour channels. We also consider the possibility that laser treatment for this condition does not affect macula function. Methods: We tested for the possibility of a selective colour channel involvement in 35 eyes of 33 cases of proliferative diabetes by considering the outcomes of saturation and hue testing before and after pan-retinal photocoagulation (PRP). Saturation testing was achieved with the Sahlgren Saturation Test (SST) and hue testing was via the Farnsworth-Munsell 100 (FM100) hue test. Our results were compared to a recent model1 that was developed to predict the saturation processing of diseased eyes. Results: All diabetic eyes with normal hue (FM100) scores passed the saturation test (SST). Most pre-treatment eyes (29 of 35 or 83 per cent) failed the FM100 hue test but only 16 of 35 (46 per cent) failed the saturation test. Following laser treatment, 97 per cent of eyes were abnormal on the FM100 hue test but only seven per cent failed the saturation test. © 1998 Optometrists Association Australia.