Comparative Analytical Study of Intravitreal Triamcinolone Acetonide Versus Bevacizumab in Managing Diabetic Macular Edema: Insights From a Tertiary Eye Care Facility in India

Aim: This study aims to compare the effects of intravitreal triamcinolone acetonide (IVTA) and bevacizumab (IVB) in diabetic macular edema (DME) management.

Methodology: A prospective interventional study was conducted at a tertiary eye care hospital in Tamil Nadu, India. The study received approval from the institutional ethics committee, and informed consent was obtained from all participants. Inclusion criteria comprised patients aged 18 years and above, diagnosed with macular edema attributable to non-proliferative diabetic retinopathy (NPDR), exhibiting best-corrected visual acuity (BCVA) worse than 6/18, and presenting a medical indication for either IVTA or IVB. Exclusion criteria included the presence of other ocular diseases, proliferative diabetic retinopathy, ocular inflammation, prior interventional treatments for DME, and pregnancy. Baseline assessments were comprehensive and included evaluations of BCVA, intraocular pressure (IOP) measurements, slit-lamp biomicroscopy, fundus photography, and optical coherence tomography (OCT). Participants in both groups adhered to standardized injection protocols and post-injection care routines, with follow-up monitoring scheduled at one week and one, three, and six months post-treatment. The primary outcome measures comprised changes in BCVA, IOP, findings from slit-lamp, and fundus examinations, alongside assessments of macular thickness through OCT and fundus photography. Statistical analyses were performed in SPSS Statistics version 25 (IBM Corp. Released 2017. IBM SPSS Statistics for Windows, Version 25.0. Armonk, NY: IBM Corp.), ensuring rigorous evaluation of the collected data.

Results: A study involving 50 patients with NPDR and clinically significant macular edema compared the effects of IVTA and IVB. In Group I (IVTA), significant improvements in BCVA were observed at both one and three months; however, there was a slight decline in vision by six months. The reduction in central foveal thickness (CFT) was sustained in this group, but IOP increased, with one case necessitating surgical intervention. In Group II (IVB), BCVA improvement was quicker at one and three months, yet by six months, both vision and CFT worsened significantly. Notably, IVB maintained stable IOP throughout the study. While IVTA demonstrated a more prolonged effect on macular thickness, it was associated with higher risks related to IOP, whereas IVB provided faster, albeit less durable, outcomes.

Conclusion: Both IVTA and IVB effectively enhance visual acuity and reduce macular edema in diabetic retinopathy. IVB demonstrates superior short-term gains in visual acuity (over one to three months). In contrast, IVTA is more effective in decreasing CFT, thanks to its broader mechanism of action, including inhibition of vascular endothelial growth factor and cytokines. The longer half-life of IVTA provides more sustained anatomical benefits but is associated with higher IOP, necessitating careful monitoring. Conversely, IVB presents fewer complications, making it a safer option for certain patients. Treatment choice should consider the patient's risk profile, balancing efficacy with potential side effects.