Diabetic retinopathy: should this patient receive laser treatment?

Series editors: Susan Lightman and Peter McCluskey

Correspondence to:
E Y Chew
Building 31, Room 6A52, 31 Center Drive, MSC 2510, Bethesda, MD 20892-2510, USA; echew@nei.nih.gov

Accepted for publication 12 May 2003

Keywords: diabetic retinopathy; macular oedema; vision loss; vitrectomy

This 53 year old man has had diabetes for approximately 18 years. He has recently experienced a mild decrease in his right visual acuity 20/30 (6/9). His medications include insulin and oral hypoglycaemic agents and his most recent haemoglobin A1C is 9.4%. At this visit, his blood pressure is 125/90. His fasting serum cholesterol level is 247 mg/dl (6.39 mmol/l) while his low density lipoprotein (LDL) cholesterol is 143 mg/dl (3.67 mmol/l). He has moderate cortical lens opacities in both eyes. The fundus examination revealed more severe changes in his right eye with the presence of marked haemorrhages in the four mid-peripheral quadrants (fig 1) with evidence of intraretinal microvascular abnormalities (IRMA) and venous abnormalities in the infranasal quadrant (fig 2). In the right macula, retinal hard exudate can be detected superotemporal to the centre of the fovea (fig 3). In his left eye, he has similar but fewer changes of retinal haemorrhages in all four mid-peripheral quadrants and no evidence of IRMA, venous abnormalities, or retinal hard exudate. His left vision is 20/20 (6/6).

Figure 1 The superotemporal quadrant of the retina showed moderate retinal haemorrhages.

Figure 2 There is evidence of intraretinal microvascular abnormalities (IRMA) and venous abnormalities in the infranasal quadrant.

Figure 3 In the right macula, retinal hard exudate can be detected superotemporal to the centre of the fovea.

What steps should be taken to evaluate and treat this patient?