Role of retinal hypoxia in diabetic macular edema: a new concept.

BACKGROUND: To report the role of retinal hypoxia in development of diabetic macular edema and its management--a new concept.

CASE REPORT: A 24-year-old diabetic female was seen with bilateral visual blurring for 3 weeks, associated with marked diabetic macular edema, diabetic retinopathy, and non-arteritic anterior ischemic optic neuropathy (NA-AION) in both eyes. She was taking three blood pressure lowering drugs for diabetic neuropathy and nephropathy. Stopping two of those arterial hypotensive drugs, without any of the conventional treatments for diabetic macular edema, resulted in rapid improvement of visual acuity from counting fingers to 20/50 in the right eye, and from 20/80 to 20/25 in the left eye, and complete resolution of macular edema and improvement of retinopathy. Similarly, visual field defects in both eyes improved to almost normal.

CONCLUSIONS: The evidence from this diabetic patient suggests that hypoxia caused by fall in perfusion pressure in the retinal capillaries may be playing an important role in the development of diabetic macular edema in some, perhaps many, of these cases.