Effect of Repeated Intravitreal Injections in Glaucoma Spectrum Diseases

Rodrigo Vilares-Morgado; Vera Correia; Ana Margarida Ferreira; Flávio Alves; António Benevides Melo; Sérgio Estrela-Silva; Joana Araújo; João Tavares-Ferreira; Marta Silva; Amândio Rocha-Sousa; Angela Carneiro; João Barbosa-Breda

doi:10.2147/OPTH.S441500

Effect of Repeated Intravitreal Injections in Glaucoma Spectrum Diseases

Clin Ophthalmol. 2023 Nov 22:17:3613-3627. doi: 10.2147/OPTH.S441500. eCollection 2023.

Authors

Rodrigo Vilares-Morgado^{1

2}, Vera Correia³, Ana Margarida Ferreira¹, Flávio Alves¹, António Benevides Melo^{1

3}, Sérgio Estrela-Silva^{1

3}, Joana Araújo^{1

3}, João Tavares-Ferreira^{1

3}, Marta Silva¹, Amândio Rocha-Sousa^{1

2}, Angela Carneiro^{1

2}, João Barbosa-Breda^{1

2

4}

Affiliations

¹ Department of Ophthalmology, Centro Hospitalar e Universitário de São João, Porto, Portugal.
² UnIC@RISE, Department of Surgery and Physiology, Faculty of Medicine of the University of Porto, Porto, Portugal.
³ Faculty of Medicine, University of Porto, Porto, Portugal.
⁴ KULeuven, Research Group Ophthalmology, Department of Neurosciences, Leuven, Belgium.

Abstract

Purpose: To evaluate whether repeated intravitreal injections (IVI) with an anti-vascular endothelial growth factor (anti-VEGF) agent are associated with glaucomatous progression in eyes with glaucoma spectrum diseases (GSD).

Methods: Single-center, retrospective, longitudinal study of patients with bilateral and similar GSD who: (1) received ≥8 IVI in only one eye during the study period; (2) had ≥2 retinal nerve fiber layer thickness (RNFL) measurements obtained by spectral-domain optical coherence tomography (SD-OCT) at least 12 months apart. The primary outcome was the absolute RNFL thickness change, comparing injected and fellow uninjected eyes. Linear mixed effects models were constructed, including a multivariable model.

Results: Sixty-eight eyes from 34 patients were included, 34 injected and 34 fellow uninjected eyes. Average baseline age was 67.68±21.77 years with a follow-up of 3.66±1.89 years and 25.12±14.49 IVI. RNFL thickness decreased significantly from 80.92±15.78 to 77.20±17.35 μm (p<0.001; -1.18±1.93 μm/year) in injected eyes and from 79.95±17.91 to 76.61±17.97 μm (p<0.001; -1.07±0.98 μm/year) in uninjected eyes. In a multivariable linear mixed model of injected eyes, only higher baseline RNFL thickness (p < 0.001) significantly predicted higher absolute RNFL thickness loss. Neither absolute RNFL thickness variation (p=0.716) nor RNFL rate (p=0.779) was significantly different between paired injected and uninjected eyes. Absolute IOP variation was not significantly different between groups (16.62±4.77 to 15.09±4.34 mmHg in injected eyes and 17.68±5.01 to 14.50±3.39 mmHg in fellow uninjected eyes; p=0.248). The proportion of eyes receiving glaucoma medical treatment increased significantly in both groups (55.9% to 76.5% in injected eyes; p=0.039; 58.8% to 76.5% in uninjected eyes; p = 0.031). The number of glaucoma medications also increased significantly in both groups (1.03±1.11 to 1.59±1.18 glaucoma medications in injected eyes; p=0.003; 1.09±1.11 to 1.56±1.19 glaucoma medications in uninjected eyes; p=0.003).

Conclusion: Repeated IVI do not seem to accelerate glaucomatous progression. Future studies with a longer follow-up are needed.

Keywords: glaucoma; intravitreal injections; optical coherence tomography; progression; retinal nerve fiber layer thickness.

Grants and funding

The authors declare that they have no financial ties to declare. No funding or sponsors were undertaken in the preparation of the manuscript.