During an annual eye examination, a 65-year-old woman with a 5-year history of type 2 insulin-dependent diabetes complained that her vision had slightly worsened in both eyes. Her best corrected visual acuity was 20/30 in both eyes. Ophthalmoscopic examination revealed nonproliferative diabetic retinopathy changes, including dot-blot hemorrhages that originated in the middle layers of the retina. Areas of yellow, waxy, hard exudates composed of lipoprotein and lipid-filled macrophages were seen forming clumps and circinate rings adjacent to and involving the macula. Stereoscopic examination of the macula confirmed macular thickening. No cotton-wool spots or areas of neovascularization were noted (A and B). Diabetic maculopathy was confirmed by a fluorescein(Drug information on fluorescein) angiogram, which revealed leaking microaneurysms that caused the retinal thickening and the hard exudates. A focal argon laser treatment was performed in each eye to resolve the macular edema, encourage resorption of leaked fluid, and treat leaking vessels and microaneurysms to prevent further leakage. Laser treatment for clinically significant macular edema is recommended if one or more of the following findings is present:
- Retinal edema (thickening) within 500 µm of the center of the fovea.
- Hard exudates within 500 µm of the fovea, if associated with adjacent retinal thickening (which may be outside the 500-µm limit).
- Retinal edema that is 1 disc area (1500 µm) or larger, any part of which is within 1 disc diameter of the center of the fovea.1
- This patient required only a single laser treatment. Additional treatments can be given if complete resorption is not achieved after 2 to 3 months.