Short-term efficacy of posterior sub-tenon injection of triamcinolone acetonide in macular edema due to ischemic retinal vein occlusions

Objective To observe the short-term efficacy of posterior sub-tenon injection of triamcinolone acetonide (PSTA) in the treatment of macular edema due to ischemic retinal vein occlusions (RVO). Methods A retrospective clinical study. A total of 53 eyes of 53 patients with RVO macular edema diagnosed by fundus color photography, fundus fluorescein angiography and optical coherence tomography (OCT) were included in the study. The best corrected visual acuity (BCVA) was detected by the international standard visual acuity chart, and the results were converted to the logarithm of the minimum angle of resolution (logMAR) visual acuity. The central macular thickness (CMT) was measured by OCT. Among 53 eyes, there were 27 eyes with ischemic RVO macular edema (ischemic group) and 26 eyes with non-ischemic RVO macular edema (non-ischemic group). The mean logMAR BCVA was 0.82±0.37, mean CMT was (662.1±216.7) μm in ischemic group. The mean logMAR BCVA was 0.41±0.23, mean CMT was (548.0±161.9) μm. The differences of logMAR BCVA and CMT between the two groups were both statistically significant (t=4.745, 2.258; P<0.05). All eyes were treated with a single sub-Tenon injection of 0.4 ml triamcinolone acetonide suspension (100 mg/ml). The mean logMAR BCVA, CMT before and 1, 3 months after the treatment between the two groups were observed and compared. Results On 1 and 3 months after treatment, the mean logMAR BCVA in the non-ischemic group (0.32±0.25 and 0.27±0.29) were improved compared with ischemic group (0.76±0.37 and 0.41±0.79), the difference was statistically significant (t=5.052, 5.240; P 0.05), but had a statistically significant difference in non-ischemic group (F=7.685, P 0.05). On 1 month after the treatment, there were 3 and 5 eyes had a higher intraocular pressure than 21 mmHg (1 mmHg=0.133 kPa) in ischemic and non-ischemic group, respectively; but all of them returned to normal after drug treatment. There were no drugs and ocular injection related complications. Conclusion PSTA of ischemic RVO macular edema can lower the CMT in the short term, but can′t significant improve the visual acuity. Key words: Retinal vein occlusion/drug therapy; Macular edema /drug therapy; Triamcinolone acetonide/therapeutic use