Irregular dilation of the retinal venules (venous beading) has long been known to be an important clinical sign of diabetic retinopathy severity and a signal of impending progression to vision-threatening stages of proliferative disease.1 Traditionally, ophthalmologists have been able to identify prominent venous beading clinically, but they may not be able to distinguish milder and more generalized dilatation of the venules with precision.
Wong TY. Retinal Vessel Diameter as a Clinical Predictor of Diabetic Retinopathy ProgressionTime to Take Out the Measuring Tape. Arch Ophthalmol. 2011;129(1):95-96. doi:10.1001/archophthalmol.2010.347