Objective.— To clarify the frequency and characteristics of altered transverse sinus morphology in a series of consecutive patients with chronic migraine.
Background.— As terminology, neuroradiological techniques and patient selection differ widely across various studies, reliable, reproducible information is lacking on the frequency of cerebral transverse sinus asymmetry as measured by cerebral magnetic resonance venography in patients with chronic migraine.
Methods.— We assessed the frequency and characteristics of transverse sinus asymmetries and their correlation with the chronic migraine phenotype in a blind, cross-sectional magnetic resonance venographic study in a series of 83 consecutive patients with chronic migraine.
Results.— After excluding mild (≤10%) physiological differences in transverse sinus diameter, we found magnetic resonance venographic evidence of altered transverse sinus morphology in 50.6% of the patients: 16.9% had moderate transverse sinus asymmetry (≤50%), 24.1% severe asymmetry (>50%), and 9.6% aplasia. Among the tested risk factors for migraine chronification, analgesic consumption, anxiety, and high systolic blood pressure were more frequent in patients with transverse sinus aplasia than in those without.
Conclusions.— Advanced magnetic resonance venographic techniques used in strictly selected subjects disclose transverse sinus asymmetries in as many as 50.6% of patients with chronic migraine, even when mild differences in physiological caliber are excluded. The unexpected correlation between transverse sinus aplasia and some risk factors for migraine chronification requires confirmation in larger studies.