Migraine or idiopathic intracranial hypertension: Magnetic resonance venography and magnetic resonance imaging findings.

BACKGROUND: Idiopathic intracranial hypertension (IIH) is a disease characterised by increased cerebral pressure without a mass or hydrocephalus. We aimed to differentiate migraine and IIH patients based on imaging findings.
RESULTS: Patients with IIH (n = 32), migraine patients (n = 34) and control subjects (n = 33) were evaluated. Routine magnetic resonance imaging, contrast-enhanced 3D magnetic resonance venography and/or T1-weighted 3D gradient-recalled echo were taken with a 1.5 T magnetic resonance scanner. Optic-nerve sheath distention, flattened posterior globe and the height of the pituitary gland were evaluated in the three groups. Transverse sinuses (TS) were evaluated with respect to score of attenuation/stenosis and distribution. Pearson chi-square, Fisher's exact test and chi-square trend statistical analyses were used for comparisons between the groups. A p-value of <0.05 was considered statistically significant. Decreased pituitary gland height, optic-nerve sheath distention and flattened posterior globe were found to be statistically significant (p < 0.001) in IIH patients. Bilateral TS stenosis was also more common in IIH patients than in the control group and migraine group (p = 0.02).
CONCLUSION: Decreased pituitary gland height, optic-nerve sheath distention, flattened posterior globe, bilateral stenosis and discontinuity in TS are significant findings in differentiating IIH cases from healthy individuals and migraine patients. Bilateral TS stenosis may be the cause rather than the result of increased intracranial pressure. The increase in intracranial pressure, which is considered to be responsible for the pathophysiology of IIH, is not involved in the pathophysiology of migraine.