Flame‐shaped hemorrhage seen in diabetic retinopathy is indicative of macular ischemia

Abstract

Abstract Purpose To study oxygen saturation(OS) levels in the macula with non‐proliferative diabetic retinopathy. Methods 60 eyes of 46 diabetic patients were enrolled in this study. The eyes were divided into three groups based on additional fundus findings. 16 eyes had flame‐shaped hemorrhages near the optic disk(group H). 20 eyes had soft exudates throughout the fundus(group E) and 24 eyes had neither flame‐shaped hemorrhages nor soft exudates (group N). Patient`s age were 57±9.6, 58±8.5 and 54±16.2 years, respectively in each group. Exclusion criteria were eyes with macular edema treated with laser coagulation. The extent of capillary non‐perfusion was evaluated using fluorescein angiogram divided into macula and 4 peripheral quadrants. The severity of non‐perfusion was graded from 0 to 5 in a masked fashion. The OS level was measured only in the macular area using Fourier transform‐based spectral retinal imaging (SRI) system (Retinal Cube;ASI Co.Israel). Results The OS levels in the macula did not correlate with overall extent of capillary non‐perfusions in the fundus. However group H showed a tendency to have lesser area of capillary non‐perfusion when compared with group E or N. The OS levels of H,E and N group were 63±6.7,68±6.2,and 74±8.5% respectively. The difference between OS levels in group H and N and between group E and N were statistical significance (p<0.01 and p<0.05 respectively). Conclusion The OS levels in the macular area of the retinas with non‐proliferative retinopathy were lowest in the retinas with flamed‐shaped hemorrhage. Surprisingly, the overall degree of capillary non‐perfusion of the fundus did not correlate with macular OS level. Our study shows that flame shaped hemorrhages are indicative of macular ischemia.