Abstract
Purpose: :
To determine the efficacy of posterior subtenon’s (PST) injection of triamcinolone acetonide in the treatment of diabetic macular edema (DME) refractory to focal laser photocoagulation.
Methods: :
A retrospective review was conducted of all patients who received PST injection of triamcinolone acetonide for DME from October 2006 to October 2007 at the Stroger Hospital of Cook County Division of Ophthalmology Retina Service. All patients had a comprehensive eye exam including best corrected Snellen visual acuity, slit lamp biomicroscopy with indirect ophthalmoloscopy, intraocular pressure measurement and central macular thickness measurement (CMT) by optical coherence tomography (OCT) fast macula program at each visit. Posterior subtenon’s injection of triamcinolone acetonide 1.0cc (40mg/cc) was administered by the Nozik technique. All patients had received at least one focal laser photocoagulation treatment prior to the start of the study, and fluorescein angiography was performed prior to the first injection.
Results: :
A total of 19 eyes of 17 patients were included in the study. Exclusion criteria were based on the following: history of prior panretinal laser, history of prior PST or intravitreous triamcinolone acetonide injection, macular edema secondary to other etiologies, visual acuity better than 20/30 or lack of follow-up. Of the 17 patients included, 12 were female. The average age was 50 years (range 35 to 83 years). All were type 2 diabetics, and 9 were insulin requiring. Mean follow-up time was 142 days (range 35-392 days). Three eyes received a second PST triamcinolone acetonide injection for worsening vision and/or increased central macular thickness (CMT). Mean pre-injection CMT was 385µm (range 153 to 603µm), and the mean post-injection CMT was 327µm (range 121 to 563µm). This difference was statistically significant (p<0.05). Visual acuity improved by 2 or more lines in 4 eyes, worsened in 3 eyes and remained the same in 12 eyes. Snellen visual acuity was converted to Log MAR for the purposes of statistical analysis. There was no statistically significant difference between pre- and post-injection visual acuity (p>0.05).
Keywords: diabetic retinopathy • clinical (human) or epidemiologic studies: outcomes/complications • macula/fovea