Hypertension correlates with the severity of the diabetic retinopathy. Monkeys with type 2 diabetes have many of the angiopathic changes associated with human diabetic retinopathy. This is the first detailed analysis of retinopathy in a colony of spontaneous type 2 diabetic monkeys. In elastase-digested retinas, the ratio of pericytes to endothelial cells was 0.66:1 in diabetic and 0.64:1 in nondiabetic (P = 0.75) retinas. There was a significant correlation between the occurrence of retinopathy and hypertension (P = 0.037 for systolic pressure P = 0.019 for diastolic pressure). There were apparent fluid-filled spaces in the outer plexiform layer in three of these maculas, suggesting macular edema. Formation of small intraretinal microvascular abnormalities (IRMAs) and microaneurysms were associated with the areas of nonperfusion. Large nonperfused areas extending from optic disc to midfovea were observed in four diabetic monkeys. Dot/blot hemorrhages, cotton-wool spots, and small nonperfused areas were the earliest histologically documented changes in the retinas. Tissue sections were cut through areas of interest.Ĭotton-wool spots, intraretinal hemorrhages, and hard exudates in the macula were observed by ophthalmoscopy in some diabetic monkeys. Retinas from 16 diabetic monkeys and 6 nondiabetic monkeys were incubated postmortem for adenosine diphosphatase (ADPase) activity (labels viable retinal blood vessels) and flat-embedded in JB-4. Ophthalmoscopic examinations were performed on aged normal and diabetic monkeys. The purpose of this study was to investigate clinically and histopathologically the ocular changes in these monkeys. The examiners were blinded to these factors.Type 2 diabetes occurs spontaneously in rhesus monkeys and shows an extraordinary similarity to human diabetes in clinical features and relative time course. Retinopathy was also considered to be present in participants with central retinal artery or vein occlusion. A A case of severe non-proliferative retinopathy is characterized by venous changes (circle), micro-aneurysms and dotblot hemorrhages (small red spots). Factors assessed before examination included time since delivery, length of labor, method of delivery, use of forceps, gestational age, Apgar scores, birthweight, head circumference, maternal parity, occurrence of episiotomy, maternal analgesic, maternal anesthesia, and induction of labor. Retinopathy was defined as the presence of one or more dot/blot hemorrhages, microaneurysms, hard exudates, cotton wool spots, or evidence of laser treatment for retinopathy in 1 eye (Figure (Figure1A). Visuals of retinopathies, as observed by fundoscopic methods and with an emphasis on the most common pathologies of diabetic retinopathy. ![]() Degree or severity of hemorrhage was classified into 3 categories: Grade I, 1 or 2 hemorrhages Grade II, 3–10 hemorrhages and Grade III, 10 or more hemorrhages. Hemorrhages were classified into 3 zones defined by distance from the optic nerve head and fovea, progressing peripherally from Zone I to Zone III. In subacute or late presentations in which disc swelling has resolved (with or without collateral vessel formation), the flame-shaped hemorrhages clear first, leaving deeper dot/blot hemorrhages that may be difficult to distinguish from a severe microangiopathic retinopathy such as diabetic retinopathy ( Fig. If retinal hemorrhage (RH) was detected, indirect ophthalmoscopy was repeated every 2 weeks until the RHs were no longer evident. ![]() Infants with known or suspected systemic or ocular disease were excluded from the study and retinal specialists examined all subjects within 30 hours of birth. The authors report a cross-sectional study of 149 newborn babies free of known medical problems admitted to the Well Baby Nursery of the Children’s Hospital of Yale-New Haven Medical Center over a period of 65 weekdays.
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