Baseline Subfoveal Choroidal Thickness as a Predictor for Response to Short-Term Intravitreal Bevacizumab Injections in Diabetic Macular Edema

Abstract

Purpose

This article aims to evaluate how the subfoveal choroidal thickness (SFCT) and best-corrected visual acuity (BCVA) respond to the intravitreal injection of bevacizumab and to assess the correlation between these changes. It will also assess the use of the baseline SFCT as a predictor for BCVA changes in eyes of treatment-naive, diabetic macular edema (DME) patients.

Methods

This retrospective, consecutive case series comprised 59 eyes of 39 treatment-naive DME patients. Complete slit-lamp assessment, swept-source optical coherence tomography (SS-OCT) scans to measure SFCT and BCVA values were performed at two stages: baseline and one month after the third monthly injection of intravitreal bevacizumab.

Results

Patients’ ages ranged from 46.3 to 76.4 years (mean: 62.6 ± 2.3). The mean SFCT was 318 ± 82 μm at baseline, which decreased after 3 months to 300 ± 66 μm (P-value = 0.021). There was an improvement in the mean of the logMAR best-corrected visual acuity (BCVA) from 0.7 (decimal equivalent: 0.2) to 0.5 (decimal equivalent: 0.3) (P-value = 0.019). There was no association between SFCT changes and BCVA changes (P-value = 0.180). Wilcoxon signed-rank test disclosed that a better BCVA improvement was related to a greater subfoveal choroidal thickness at baseline P-value <0.00.

Conclusion

Eyes with a higher baseline subfoveal choroidal thickness (SFCT) attained greater BCVA improvement than eyes with a lower baseline SFCT. In addition to this, changes to SFCT do not appear to correlate with BCVA changes. These findings do not support using OCT SFCT changes as a prognostic factor for changes to BCVA after intravitreal bevacizumab treatment in evaluating treatment-naive DME eyes.

Keywords:

• diabetic macular edema
• subfoveal choroidal thickness
• best-corrected visual acuity
• bevacizumab
• anti-vascular endothelial growth factor

Acknowledgments

All study authors would like to thank the optometrists in the ophthalmology department of An-Najah National University Hospital for their assistance in the current work, the clinical research center team at An-Najah National University Hospital for their support of this research study, and Samantha Kearly from Southmead Hospital, Bristol, UK for her assistance in language editing.

Disclosure

The authors declare that we have no conflict of interest in this study.