Evaluation of Brain Magnetic Resonance Indices in Migraine and Cluster Headache Patients

Aim: This study aimed to compare neuroanatomical indices measured by magnetic resonance imaging (MRI), including the bicaudate index (BCI), bifrontal index (BFI), Evans index, fourth ventricle index (FVI), and corpus callosum index (CCI), across patients with migraine with and without aura, cluster headache, and healthy controls, to identify structural differences and elucidate the pathophysiological mechanisms underlying these disorders. Material and Methods: A total of 144 participants aged 20-50 years were retrospectively analyzed and evenly divided into four groups: migraine with aura, migraine without aura, cluster headache, and healthy controls. Neuroanatomical measurements were obtained from archived MRI scans performed using a 1.5 Tesla device. All indices were calculated using standardized linear formulas and verified by a radiologist blinded to the diagnostic groups. Results: Significant differences were observed among the groups in BCI, BFI, and Evans index (p=0.047, p=0.010, and p=0.010, respectively). The BCI was significantly lower in the migraine with aura group compared to the cluster headache group (p=0.041). BFI (p=0.010) and Evans index (p=0.006) were notably reduced in the migraine without aura group compared to controls. No significant differences were found in FVI (p=0.172) and CCI (p=0.967). Conclusion: These findings reveal the presence of structural brain differences in patients with migraine and cluster headache. Changes in BCI, BFI, and Evans index may reflect underlying neuroanatomical mechanisms and could be considered potential biomarkers for diagnosis and individualized treatment strategies. They may also support the development of mechanism-based imaging strategies in the clinical evaluation of headache.