Center-involving Macular Edema Research Articles

Diabetic macular edema: changing treatment paradigms.

To review the current management and recent changes in treatment paradigm for diabetic macular edema (DME). During the review period (1 year), several prospective studies analyzed the beneficial effect of anti-vascular endothelial growth factor agents in the management of DME. An exploratory analysis concluded that intravitreal ranibizumab appears to be associated with a reduced risk of diabetic retinopathy worsening. A randomized, controlled, multicenter, double-masked, parallel-group, 12-month trial to evaluate a dexamethasone intravitreal implant (DEX implant) combined with laser photocoagulation compared with laser alone for treatment of DME concluded that there was no significant between-group difference at month 12. A multicenter, prospective, observational study found that in eyes with diabetic retinopathy without concurrent central-involved DME, presence of noncentral-involved DME immediately prior to cataract surgery or history of DME treatment may increase the risk of developing central-involved macular edema after cataract extraction. Another randomized trial to evaluate whether intravitreal ranibizumab injection at cataract surgery prevents postoperative DME concluded that intravitreal ranibizumab injection at cataract surgery may prevent the postoperative worsening of macular edema. The results of clinical trials have shown the superiority of some of these anti-vascular endothelial growth factor agents to laser therapy. However, with the availability of several of these newer agents, it may be difficult to individualize treatment options, especially if DME patients respond differently to various therapies.

Randomized Controlled Trial of Intravitreal Ranibizumab Versus Standard Grid Laser for Macular Edema Following Branch Retinal Vein Occlusion

To assess the efficacy of intravitreal 0.5 mg ranibizumab for the treatment of center-involving macular edema secondary to branch retinal vein occlusion (BRVO) over 1 year compared with standard-of-care grid laser. A prospective randomized controlled clinical trial. A total of 36 patients with vision loss in 1 eye attributable to macular edema following BRVO were recruited from 5 institutions. Patients were randomized 1:1 to a treatment group that received 6 monthly injections of 0.5 mg ranibizumab and thereafter monthly as needed based on best-corrected visual acuity (BCVA) and central foveal thickness (CFT) assessments on optical coherence tomography scans, or a standard-of-care group that received monthly sham injections for the 1-year duration of the study. Grid laser was administered at 13 and 25 weeks in both groups if criteria for laser treatment were met. Main outcome measures included mean change in BCVA in Early Treatment Diabetic Retinopathy Study (ETDRS) letter scores from baseline to month 12. Secondary outcomes included anatomic outcomes and the percentage of patients requiring grid laser in both groups. Mean BCVA change from baseline was significantly greater in the treatment compared with the standard-of-care group at 12 months (12.5 ETDRS letters vs -1.6 ETDRS letters, P = .032). The mean CFT was significantly reduced in the treatment compared with standard-of-care group (361.7 μm vs 175.6 μm, P = .025). At 13 and 25 weeks, more patients in the standard-of-care group (68.4%, 50.0%) received grid laser than in the treatment group (6.7%, 8.3%). No new ocular or systemic adverse events were observed. Compared with standard grid laser, intravitreal ranibizumab provided significant and sustained benefits in visual acuity gain and anatomic improvement in eyes with macular edema secondary to BRVO.

Macular Edema After Cataract Surgery in Eyes Without Preoperative Central-Involved Diabetic Macular Edema

The incidence of development or worsening of macular edema (ME) is variable in eyes without diabetic ME (DME) undergoing cataract surgery. To estimate the incidence of central-involved ME 16 weeks following cataract surgery in eyes with diabetic retinopathy without definite central-involved DME preoperatively. In a multicenter, prospective, observational study, 293 participants with diabetic retinopathy without definite central subfield thickening on optical coherence tomography (OCT) underwent cataract surgery. Cataract extraction surgery performed within 28 days of enrollment of eyes without DME in individuals with diabetes mellitus. Development of central-involved ME defined as the following: (1) OCT central subfield thickness of 250 μm or greater (time-domain OCT) or 310 μm or greater (spectral-domain OCT) with at least a 1-step increase in logOCT central subfield thickness preoperatively to the 16-week visit; (2) at least a 2-step increase in logOCT central subfield thickness preoperatively to the 16-week visit; or (3) nontopical treatment for ME received before the 16-week visit with either of the OCT criteria met at the time of treatment. The median participant age was 65 years. The median visual acuity letter score was 69 letters (Snellen equivalent 20/40). Forty-four percent of eyes had a history of treatment for DME. Sixteen weeks postoperatively, central-involved ME was noted in 0% (95% CI, 0%-20%) of 17 eyes with no preoperative DME. Of eyes with non-central-involved DME, 10% (95% CI, 5%-18%) of 97 eyes without central-involved DME and 12% (95% CI, 7%-19%) of 147 eyes with possible central-involved DME at baseline progressed to central-involved ME. History of DME treatment was significantly associated with central-involved ME development (P < .001). In eyes with diabetic retinopathy without concurrent central-involved DME, presence of non-central-involved DME immediately prior to cataract surgery or history of DME treatment may increase the risk of developing central-involved ME 16 weeks after cataract extraction.