Advantage:

Diabetic macular edema (DME) with serous macular detachment (SMD) responds poorly to laser treatment due to presence of subretinal fluid but has been seen to resolve following both IVB and IVTA. Re-injections maybe required owing to their limited period of action. We, thus, compared the efficacy of IVTA and IVB followed by laser photocoagulation, in treating DME with SMD.

Methods:

In this prospective interventional case series, 40 eyes with DME and SMD on optical coherence tomography (OCT) were enrolled. 20 eyes were given 1.25 mg/0.05 ml IVB (group A), while 20 eyes were given 4 mg/0.1ml IVTA (group B), followed 1 month later by macular grid. Patients were followed up for 4 months with respect to best-corrected visual acuity (BCVA), intraocular pressure (IOP), fluorescein angiography (FFA) and height of SMD at fixation point as measured on OCT.

Effectiveness / Safety: 

Mean age of patients in the study was 52.6± 8.75 years. The mean duration of diabetes was 5.8± 3.3 years and mean value of glycosylated haemoglobin was 6.6  ± 0.64%. Pre-injection, mean SMD height was 182.2  ± 98.19 microns in group A while it was 161.53± 76.23 microns in group B. The mean NRT (neuroretinal thickness) was 302.93 µ pre-injection in group A, while it was 274.8 µ in group B. At 1 month, SMD persisted in 6 eyes in group A while in group B, it persisted in 2 eyes. However at 4 months, only 3 eyes in group A had residual SMD. Mean BCVA improved from 0.12 at baseline to 0.35 at 4 months in group A (p=0.001) while it improved from 0.10 at baseline to 0.29 at 4 months (p=0.001) in group B. Mean macular thickness declined from 455.1 µ at baseline to 259.6 µ at 4 months (p=0.000) in group A while it declined from 422.9 µ at baseline to 261.2 µ at 4 months (p=0.000) in group B. Although both groups showed significant decrease in the mean macular thickness at the end of 4 months, there was no significant difference between the two groups. The height of SMD and NRT correlated weakly with BCVA (coefficient of correlation= -0.278 and -0.153). SMD and NRT also correlated weakly (coefficient of correlation= -0.24); indicating that they behave independently of each other. 6 patients in group B showed progression in cataract while 3 patients had IOP>21 mm that was controlled medically.

Conclusion:

Both IVB and IVTA followed by macular photocoagulation are an equally effective and long lasting modality for DME with SMD. However, IVTA has higher risk of glaucoma and cataract formation.