Clinical Ophthalmology (Nov 2023)
Effect of Repeated Intravitreal Injections in Glaucoma Spectrum Diseases
Abstract
Rodrigo Vilares-Morgado,1,2 Vera Correia,3 Ana Margarida Ferreira,1 Flávio Alves,1 António Benevides Melo,1,3 Sérgio Estrela-Silva,1,3 Joana Araújo,1,3 João Tavares-Ferreira,1,3 Marta Silva,1 Amândio Rocha-Sousa,1,2 Angela Carneiro,1,2 João Barbosa-Breda1,2,4 1Department of Ophthalmology, Centro Hospitalar e Universitário de São João, Porto, Portugal; 2UnIC@RISE, Department of Surgery and Physiology, Faculty of Medicine of the University of Porto, Porto, Portugal; 3Faculty of Medicine, University of Porto, Porto, Portugal; 4KULeuven, Research Group Ophthalmology, Department of Neurosciences, Leuven, BelgiumCorrespondence: Rodrigo Vilares-Morgado, Department of Ophthalmology, Centro Hospitalar e Universitário de São João, Alameda Professor Hernâni Monteiro, 4202 – 451, Porto, Portugal, Tel +351 914 471 067, Fax +351 225 512 100, Email [email protected]: 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, progression, optical coherence tomography, retinal nerve fiber layer thickness