Abstract
Purpose::
This study was undertaken to determine the long-term efficacy and safety of repeated injections of intravitreal triamcinolone (IVTA) for diabetic macular edema.
Methods::
We studied 27 eyes from the treatment group of a randomized clinical trial of IVTA. All eyes received IVTA for diabetic macular edema given using a standardized protocol. LogMAR visual acuity (VA) and central macular thickness (CMT) from OCT was measured at baseline and in 3 to 6 monthly intervals for up to 24 months. Eyes were categorized into the number of IVTA injections given: 1, 2, 3 and 4 or 5 injections. Main outcome measures included change in VA and CMT, need for cataract surgery and glaucoma medication
Results::
One IVTA injection was required in 6 (18%) eyes, 2 in 8 (24%) eyes, 3 in 13 (39%) eyes and 4-5 in 6 (18%) eyes. VA improved in all groups. The final improvement in VA from baseline to 24 months was not correlated with the number of injections received (p=0.44 comparing injection groups). CMT improved in all patients, but the absolute improvement in CMT from baseline to 24 months was not correlated with number of injections received (p=0.84 comparing injection groups). Cataract surgery was significantly more frequent among eyes with greater number of injections (p=0.003 comparing injection groups), and there was a trend towards increased risk of glaucoma treatment with greater number of injections (p=0.09 comparing injection groups).
Conclusions::
This study does not support the hypothesis that repeated injections of IVTA are less efficacious than the first. The risk of cataract surgery and possibly glaucoma treatment increases with increasing number of injections
Keywords: clinical (human) or epidemiologic studies: outcomes/complications • diabetic retinopathy • edema