Evaluating the impact of anti-CGRP monoclonal antibodies on retinal features in migraine patients: a retrospective optical coherence tomography study

Abstract

Background: Migraine is a disabling neurovascular disorder characterized by recurrent attacks that lead to extracranial and visual involvement. Several studies have investigated the retinal vasculature features in individuals with migraine, but there have been conflicting results.

Objective: To evaluate retinal structure in migraine patients before (T0) and after 6-month therapy (T1) with anti-calcitonin gene-related peptide (CGRP) monoclonal antibodies (mAbs), using optical coherence tomography (OCT) imaging.

Design: A case-control and longitudinal study was conducted between January 2021 and December 2023, including 20 eyes from 10 healthy controls (HCs) and 32 eyes of 16 patients with migraine and treated with anti-CGRP mAbs according to AIFA criteria.

Methods: Patients underwent OCT angiography (OCT-A) to assess retinal vessel density (VD) and spectral-domain OCT (SD-OCT) to evaluate central retinal thickness, macular structure, and peripapillary retinal nerve fiber layer thickness. These parameters were assessed in both groups at T0 and again after 6 months (T1) as part of routine clinical care.

Results: All migraineurs exhibited a significant reduction in disease disability at T1, as assessed by clinical parameters. OCT data analysis revealed that individuals with migraine showed a significant increase in temporal retinal nerve fiber layer (RNFL) thickness and a reduction in nasal RNFL thickness compared to HCs. No differences in retinal circulation were observed between the groups at baseline. At T1, RNFL thickness remained sustained in the superior temporal sector, while the percentage VD of the superficial capillary plexus and radial peripapillary capillary significantly increased in the nasal perifoveal, inferior temporal, and hemi-inferior subregions.

Conclusion: Our study suggests that specific retinal structural changes could precede vascular dysfunction in migraine and can be detected early by combining SD-OCT and OCT-A acquisitions. Short-term treatment with anti-CGRP mAbs may exert neuroprotective effects, potentially preventing permanent ocular damage.

Trial registration: EyeHEAD Study (Trial registration number AIFA July/2024: IT 1735, www.aifa.gov.it/registro-studi-osservazionali).

Keywords: CGRP; migraine; optic nerve; optical coherence tomography; retina.

Figure 1.

Spectral-domain OCT representing total retinal thickness in the macular and ETDRS area. On the right side, thickness changes between two scans at different time points are shown. OCT, optical coherence tomography.

Figure 2.

OCT-angiography scan representing vessel density in the superficial and deep retinal vascular plexi (a). Retinal flow is superimposed in red on the axial scans (b). Colorimetric maps of vessel density and retinal thickness in the ETDRS area (c). OCT, optical coherence tomography.

Figure 3.

En face representation of the superficial retinal vessel density in the ETDRS area (a). Confocal scanning laser ophthalmoscopy of the ETDRS area (b). Vessel density and OCT Thickness values of the different ETDRS sectors (c). Retinal flow is superimposed in red on the axial scans (d). Colorimetric maps of vessel density and retinal thickness in the ETDRS area (e). OCT, optical coherence tomography.

Figure 4.

Confocal scanning laser ophthalmoscopy of the optic nerve head and peripapillary area (a). Vessel density of the radial peripapillary capillary plexus (b). Colorimetric maps of optic nerve head and peripapillary area thickness (c) and vessel density (d).