Retinal & choroidal alterations in migraine patients compared to normal healthy controls

Purpose: Migraine is an incapacitating neurovascular disorder which primarily affects the working age population. Researchers have postulated that the transient vascular alterations during each migraine attack, leads to ischemic damage in the eye which can be measured via optical coherence tomography (OCT). Methods: We recruited 29 volunteers: 13 migraineurs (mean age 28±8.8 years; 12 female and 1 male) and 16 age-matched controls (mean age 26.6±6.9; 9 female and 7 male). All individuals underwent a detailed ophthalmic examination by a qualified optometrist and a Migraine Disability Assessment (MIDAS test). The investigators were blind to the migraine diagnosis. Retinal Nerve Fibre Layer (RNFL) thickness, Retinal Thickness (RT), Ganglion Cell Complex (GCL), ranging from the inner-limiting membrane to the inner plexiform layer, and Choroidal Thickness (CT) were measured using the 3D OCT-1Maestro , Topcon, a Spectral Domain OCT (SD-OCT) device. Results: : In the migraine population average RNFL was lower for several parameters however, results did not reach statistical significance. A significant decrease in the right eye inferior parafoveal ganglion cell layer in the migraine group of patients (mean = 25.15, SD = 4.08) compared to normal healthy controls (mean = 28.81, SD = 4.85; t = (27) = 2.17, p = 0.039) was documented. No other ganglion cell layer or choroidal thickness reached significance. No significant relationship between ocular thickness parameters and either MIDAS score, migraine duration or aura diagnosis was found. Conclusion: A significant decrease in the right inferior parafoveal ganglion cell layer for migraine patients was reported. All other parameters did not reach significance. This area of research would benefit from a systematic review and meta-analysis which includes the RNFL, GCL and choroidal thickness and examines the impact of migraine type and MIDAS score/grade is needed