Total macular volume as a potential biomarker in the assessment of anti-VEGF response in patients with diabetic macular edema: real-life data analysis

Abstract

Aim: To evaluate the functional and anatomic efficacy of intravitreal anti-vascular endothelial growth factor (anti-VEGF) therapy in patients with diabetic macular edema (DME) and investigate the association between central macular thickness (CMT) and total macular volume (TMV) in real-life settings.
Material and Method: In this retrospective, observational, longitudinal study 38 eyes of 23 consecutive patients with center-involving DME were included. A loading phase of three monthly intravitreal anti-VEGF injections was initiated, followed by anti-VEGF injections if needed as per clinicians’ discretion.
Results: Mean Early Treatment Diabetic Retinopathy Study (ETDRS) letters gained was 3.2 letters at month 12. The reduction in the mean of CMT and TMV were 60 μm and 1.33 mm3 respectively at the end of 12 months. Best-corrected visual acuity (BCVA) was negatively correlated with CMT (r=-0.573, p < 0.01) and TMV (r=-0.533, p < 0.01) initially. There was a statistically significant positive correlation between the CMT and the TMV initially (r=0.765, p < 0.01) and month 12 (r=0.937, p < 0.01). Baseline TMV was found to be more predictive of treatment response at the 9th month than baseline CMT.
Conclusion: It is demonstrated that TMV may be a suitable biomarker in the assessment of treatment response of the macular region when regarded as a complete three-dimensional macular unit instead of central vertical thickness only. Although the present study contributes to a better understanding of managing DME in real-life settings, further prospective, and controlled investigations are needed.

Keywords

• Aflibercept
• anti-VEGF
• central macular thickness
• diabetic macular edema
• total macular volume

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