Patients with mild-to-moderate NPDR but without macular edema. Treatment is generally not recommended. Patients should be reevaluated every 6 to 12 months because they have an increased risk of progression.5
Patients with mild-to-moderate NPDR and clinically significant macular edema (CSME). It is important for the eye specialist to assess for edema at the center of the macula because the risk of vision loss and need for treatment is greater when the center is involved. Vascular–endothelial growth factor (VEGF) is an important mediator of neovascularization and macular edema in diabetic retinopathy. For patients with center-involving CSME, intravitreous injection of an anti-VEGF agent provides significant benefit and is first-line treatment in these cases.4,29
Patients with DM (especially those with type 2 disease) who have, or are at risk of, atherosclerotic cardiovascular disease should receive statin therapy.
The Early Treatment for Diabetic Retinopathy Study evaluated the efficacy of focal photocoagulation, a painless laser therapy, for CSME and demonstrated that this modality reduces the risk of moderate visual loss; increases the likelihood of improvement in vision; and decreases the frequency of persistent macular edema.30 Focal photocoagulation has been found effective in both non-center-involving CSME and center-involving CSME.5
Patients with severe NPDR. The recommendation is to initiate full panretinal photocoagulation prior to progression to proliferative diabetic retinopathy PDR. Researchers noted a 50% reduction in vision loss and vitrectomy when patients with type 2 DM were treated with panretinal photocoagulation early, compared with those in whom treatment was deferred until PDR developed.4,31 The role of anti-VEGF treatment of severe NPDR is under investigation.4
Patients with high-risk and severe PDR. Panretinal photocoagulation is the recommended treatment for patients with high-risk and severe PDR, and usually induces regression of retinal neovascularization. In patients with CSME and high-risk PDR, the combination of anti-VEGF therapy and panretinal photocoagulation should be considered. Vitrectomy should be considered for patients who have failed panretinal photocoagulation or are not amenable to photocoagulation.4
CORRESPONDENCE Bryan Farford, DO, Mayo Clinic, 4500 San Pablo Road, Jacksonville, FL 32224; Farford.Bryan@mayo.edu.