Retinal varices are rarely observed but may be seen occasionally in association with the vascular changes which occur in the retinitis of diabetes. Sclerosis of the retinal vessels is an almost constant finding in adults who have had diabetes over a period of years. Probably such changes in the vascular system are either hastened or even brought about in some way by the metabolic disturbances associated with the disease. The retinitis of diabetes is believed to be the result of such pathologic alterations in the vascular system.
Ophthalmoscopic examinations of several hundred diabetic patients, over a period of years, revealed many with the typical signs of retinitis. Almost invariably sclerosis of the retinal vessels was in evidence, and in an occasional case varices of the retinal veins were noted. Further observations showed that these venous changes occurred almost exclusively in patients with diabetes and arteriosclerosis, but occasionally they were present
O'BRIEN CS, ALLEN JH. UNUSUAL CHANGES IN THE RETINAL VEINS IN DIABETES. Arch Ophthalmol. 1940;24(4):742–757. doi:10.1001/archopht.1940.00870040128010