Migraine causes retinal and choroidal structural changes: evaluation with ocular coherence tomography

Few studies have evaluated whether the retina is involved in migraine through the evaluation of retinal nerve fiber layer (RNFL) examined with ocular coherence tomography (OCT) with conflicting results. Aim of this case-control study is to evaluate the retina and the choroid in migraine. Patients having migraine with aura (MwA) or without aura (MoA) and chronic migraine (CM) were evaluated. Age- and sex-matched normal subjects were selected as healthy controls (HC). Patients and HC were examined with OCT. RNFL, ganglion cell layer (GCL), foveal thickness (FT), choroidal thickness (CT) and total macular volume (TMV) were calculated for right eyes (RE) and left eyes (LE). Seventy-seven patients (62 women; 80.5%), 21 MoA, 12 MwA, 44 CM and 42 HC were enrolled in the study. Patients compared to HC had a significant reduction of RNFL (RE: 91.2 ± 9.2 vs 99.3 ± 7.5 μm; p < 0.001. LE: 93.3 ± 8.7 vs 100.2 ± 6.5 μm; p < 0.001). GCL (RE: 80.6 ± 6.4 vs 86.9 ± 2.1 μm; p < 0.0001. LE: 81.5 ± 5.7 vs 87.1 ± 2.6 μm; p < 0.0001) and CT (RE: 286.4 ± 31.4 vs 333.2 ± 3.1 μm; p < 0.0001. LE: 287.2 ± 31.6 vs 334.5 ± 4.1 μm; p < 0.0001) were thinner in patients compared to HC. Moreover, CM showed reduction of RNFL and of GCL compared to the other migraineurs. Finally, we found a significant inverse correlation between RNFL thickness and total number of headache attacks per months. Our data suggest the involvement of retina and choroid in migraineurs, especially in the CM group. Although migraine is an episodic and recurrent disease, its chronic nature might cause permanent structural abnormalities involving not only the brain, but also the retina.