Abstract
Purpose::
To determine patterns of visual recovery following intravitreal triamcinolone acetonide (IVTA) for macular edema in diabetes and retinal vein occlusions.
Methods::
We retrieved 890 articles following a systematic search of Cochrane library, PubMED, MEDLINE and EMBASE databases and conducted a meta-analysis. We included articles on treatment of macular edema by IVTA in diabetes, branch retinal vein occlusion (BRVO) and central retinal vein occlusion (CRVO) in which adequate data on surgical methodology, baseline and interval visual acuity were available. 40 papers met the inclusion criteria. Visual improvement was defined as functional recovery equal or (lesser) than -2 logMAR units. Patients with both ischemic and non-ischemic maculopathy were included in this meta-analysis. Patients were treated with different dosages of IVTA in analyzed studies.
Results::
Of 1194 eyes of 1088 patients, 926 eyes had diabetic macular edema and 149 and 119 eyes had maculopathy associated with BRVO and CRVO respectively. Magnitude of visual improvement was higher in patients with retinal vein occlusions. Visual gain persisted beyond six months in BRVO patients. Visual acuity in patients with CRVO returned to baseline level at 3 months. Diabetic eyes demonstrated gradual decline of visual gain during mean follow up of 7.2 months. Amplitude of visual recovery was equivalent between higher dose > 4mg and lower dose ≤ 4mg of IVTA in diabetic eyes, but functional recovery persisted beyond 6 months in eyes that received a higher dosage. Visual gain was better and persistent at 6 months in patients with BRVO following a higher dosage of IVTA. Dose-dependent response in CRVO eyes could not be studied because of paucity of studies with higher dosages. Gradual regression of visual gain was reversed with repeat injections.
Conclusions::
Macular edema associated with BRVO responds better to IVTA when compared to diabetic macular edema. Visual recovery persists longer following a higher dose of IVTA (> 4 mg) in BRVO patients. A lower dose of IVTA (≤ 4 mg) may be adequate in diabetic maculopathy.
Keywords: macula/fovea • vascular occlusion/vascular occlusive disease • diabetic retinopathy