Accommodative performance for chromatic targets in diabetes mellitus: a preliminary report.

Our objective was to evaluate the diagnostic potential of a new vision testing procedure for detecting subclinical visual dysfunction in patients with insulin-dependent diabetes mellitus (IDDM) and minimal or absent retinopathy. We used a method which challenged both the ocular focusing and color discrimination systems simultaneously. A computerized laser speckle optometer which measured changes in ocular refraction on a subjective criterion of speckle movement rather than perceived blur was used to measure the accuracy of steady-state accommodative responses. Five volunteers between 15 and 23 years of age who had IDDM and minimal background retinopathy participated in this study. Our results for this small group of diabetics showed that: (1) the overall binocular accommodative response profiles of diabetics for colored targets through increasing negative power ophthalmic lenses did not differ markedly from those of a control population; (2) diabetics exhibited a high sensitivity for perception of optical defocus; (3) the blood glucose level influenced the extent and accuracy of accommodative responses; and (4) the overall accommodative precision, when compared to a group of nondiabetics in the same age range, showed evidence of being more reliant on target colors. The theoretical and clinical implications of these findings are discussed.