Abstract
Purpose :
A loading dose (LD) of three-monthly intravitreal injections of anti-vascular endothelial growth factor (anti-VEGF) is frequently used to determine treatment response. Here, we compare morphological and functional outcomes of bevacizumab on spectral domain-optical coherence tomography (SD-OCT) in eyes with center-involving diabetic macular edema (ciDME) pre- and post- LD.
Methods :
IRB approved observational, retrospective chart review of treatment-naïve patients with ciDME who received bevacizumab injections from 01/01/2017 to 01/19/2019 who were identified by ICD-10 code. Exclusion criteria included previous treatment with anti-VEGF or intraocular steroids in the last year, poor quality images, or incomplete chart data/missing imaging. Variables tracked included best corrected visual acuity (BCVA) and central foveal thickness (CFT) before and after LD. Central foveal OCT frames were graded qualitatively using Imagivault software, including for disorganization of retinal inner layers (DRIL) and ellipsoid zone (EZ) disruption. Analysis of variance was conducted using SPSS.
Results :
330 potential subjects were identified, and after applying exclusion criteria 24 eyes from 21 patients (mean age 65.17 ± 7.86 years, 54.2% male) were analyzed. Mean BCVA was 0.31 ± 0.19 logMar (~20/40) at baseline and 0.33 ± 0.33 logMar (~20/40) after LD. Mean CFT decreased from 449 ± 105 μm at baseline to 405 ± 113 μm after LD. Using CFT reduction metrics, 5 (20.8%) of patients were categorized as responders (>20% reduction), 6 (25.0%) as partial responders (10-20% reduction), and 13 (54.2%) as non-responders (<10% reduction). Average change in CFT from baseline in responders was -213 μm; in partial responders -68 μm, and in non-responders +32 μm. DRIL was detected in 100% of responders, 83.3% of partial responders, and 100% of non-responders. EZ disruption was present in 0% of responders, 16.7% of partial responders and 30.8% of non-responders. At baseline, responders had a significantly increased mean CFT in comparison to non-responders (p = 0.02).
Conclusions :
The response to a LD of bevacizumab in eyes with ciDME was sub-optimal with the majority of patients being non-responders. Factors indicative of a better response were increased baseline CFT and absence of EZ disruption.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.