Vitrectomy Changes Some Patients’ Response to Anti-VEGF Treatment

Choriocapillaris blood flow was improved among nonvitrectomized eyes of patients with diabetic macular edema (DME) following intravitreal ranibizumab (RBZ) therapy, according to results of a prospective longitudinal cohort study, published in Clinical Ophthalmology.

Patients (N=31; n=34 eyes) with DME were recruited between 2018 and 2019 at the Department of Ophthalmology of Centro Hospitalar e Universitário do Porto in Portugal. Patients received 0.5 mg/0.05 mL intravitreal RBZ injections every 4 weeks for up to 24 weeks. Injections were stopped if vision reached normal or stable status based on best-corrected visual acuity (BCVA) and optical coherence tomography assessed central foveal thickness (CFT).

Patients with vitrectomized (n=10) or nonvitrectomized (n=24) eyes were aged mean 66.5 and 68.4 years, 50.0% and 58.3% were women, diabetes had persisted for 22.1 and 15.7 years (P =.020), DME for 34.0 and 23.0 months, and mean glycated hemoglobin was 7.6% and 7.3%, respectively. Patient groups did not differ at baseline for choroidal vascularity parameters.

The average number of injections received was 5.18±1.17, in which the number of injections correlated with duration of diabetes (r, 0.484; P =.017) and time receiving insulin therapy (r, 0.462; P =.023).

After therapy, BCVA significantly increased among the whole population (mean, 69.7 vs 74.0 letters; P =.004) and nonvitrectomized eyes (mean, 72.3 vs 77.5 letters P =.007) and CFT decreased among the whole population (mean, 423.9 vs 339.9 µm; P <.001), vitrectomized eyes (mean, 400.5 vs 354.4 µm; P =.037), and non-vitrectomized eyes (mean, 433.7 vs 333.0 µm; P <.001).

Among the entire study population, choroidal vascularity parameters were not significantly affected. For the non-vitrectomized cohort, however, RBZ therapy associated with choroidal thickness (mean difference, −10.6 μm; P =.042) and choriocapillaris flow density (mean difference, 3.9%; P =.042) changes.

This study may have been limited by its short follow-up duration; it remains unclear whether RBZ therapy associates with long-term choriocapillaris blood flow changes.

These findings suggested that intravitreal RBZ injections increased choriocapillaris flow density and decreased choroidal thickness among patients with DME in non-vitrectomized eyes. These findings should be confirmed among a large, independent cohort to determine the lasting clinical utility of RBZ therapy among patients with DME.

Reference

Pessoa B, Marques JH, Leite J, et al. Choroidal blood flow after intravitreal ranibizumab in vitrectomized and non-vitrectomized eyes with diabetic macular edema. Clin Ophthalmol. 2021;15(10):4081-4090. doi:10.2147/OPTH.S325037