Retinal nerve fiber layer and ganglion cell layer changes using optical coherence tomography in patients with chronic migraine: a case-control study

Background Migraine is a prevalent, chronic, and multifactorial neurovascular disease. Objectives Our work aimed to investigate if the retinal nerve fiber layer (RNFL) and ganglion cell layer (GCL) thickness are affected in patients with chronic migraine to improve the understanding of the etiology and pathophysiology of migraine. Subjects and methods A case-control study conducted on 30 patients with chronic migraine and 30 aged and sex-matched healthy controls. Subjects underwent full neurological and ophthalmological history, ophthalmological examination, and measuring RNFL and GCL thickness using the spectral domain-optical coherence tomography (SD-OCT). Results RNFL thinning (average, superior, inferior, nasal, and temporal) was significantly more in patients with chronic migraine than healthy control ( P = 0.001, 0.022, 0.045, 0.034, and 0.001, respectively). No statistically significant difference was found between chronic migraine patients and healthy controls regarding GCL thickness (average, superior, and inferior) ( P value ˃ 0.05). The average RNFL thickness was significantly thinner in migraine with aura (MwA) than migraine without aura (MwoA) ( P = 0.006). The average GCL thickness was thinner in MwA than MwoA ( P = 0.039). No statistically significant difference was found between the eyes on the side of the headache and the eyes of the contralateral side regarding RNFL and GCL thickness ( P value ˃ 0.05). Age at onset, disease duration, headache frequency, and headache intensity showed an insignificant correlation with OCT parameters. Conclusion Retinal changes could be an association with chronic migraine that may be used as a biomarker.