Effect of Suprachoroidal Triamcinolone Acetonide on Intraocular Pressure in Macular Edema: A Retrospective Study.

Introduction Macular edema causes decreased vision in diseases like diabetic retinopathy, uveitis, retinal vein occlusions and post-cataract surgery cystoid macular edema. Steroids in the depot form of triamcinolone acetonide (TA) increase the duration of action, but due to a number of complications, especially raising intraocular pressure (IOP), anti-vascular endothelial growth factor (anti-VEGF) injections are now considered the mainstay of treatment. The suprachoroidal space provides an alternate route for steroid delivery, limiting the drug to the posterior segment, hence preventing the adverse effects on the anterior segment. This study aimed to determine the safety of suprachoroidal steroids with respect to their effect on IOP. Methods This retrospective study involved patients who received suprachoroidal TA injections for macular edema: diabetic retinopathy, retinal vein occlusions, uveitis and cystoid macular edema post-cataract surgery at Layton Rahmatulla Benevolent Trust (LRBT) Free Eye Hospital, Lahore, Pakistan. Manual medical records from two years were accessed and all patients were included in the study. Patients with a history of ocular hypertension, glaucoma and steroid responsiveness had not received the injection. Crystalline steroid particles of 4 mg/0.1 mL, using an intravenous TA (K-Kort; GlaxoSmithKline, Brentford, UK), were injected into the suprachoroidal space through a 30-gauge syringe with a custom plastic sleeve from a 24-gauge branula exposing 0.1 mm of the bevel. IOP was recorded at baseline before the injection and at weeks 2, 4 and 8. Repeated measures multivariate analysis of variance (ANOVA) was used to compare IOP measurements at the different time intervals. Results A total of 61 patients were included, with 70 eyes being assessed, at a mean age of 54.2 ± 10.4 years. Baseline mean IOP was 16.41 ± 2.62 mmHg, 17.04 ± 3.09 mmHg at week 2, 16.30 ± 2.95 mmHg at week 4 and 15.73 ± 1.83 mmHg at week 8. Between baseline IOP and week 2, the mean difference was 1.11 ± 0.66 mmHg (p = 0.59), 0.26 ± 0.43 mmHg from week 2 to week 4 (p = 1.00), and 1.36 ± 0.51 mmHg from week 4 to week 8 (p = 0.51). The mean IOP decreased by 0.50 ± 0.53 mmHg (p = 1.00) from baseline by eight weeks. The differences between IOP, different causes of macular edema and age or gender were not statistically significant. Two patients (1.4%) had a temporary rise in IOP above 24 mmHg requiring ocular medication, with one having a rise above 30 mmHg. Conclusion A single injection of suprachoroidal TA temporarily raises the mean IOP, but the increase is insignificant and settles to baseline by two months. Further studies would be required to establish suprachoroidal triamcinolone as a cost-effective and safe treatment for macular edema.