Relationship between Interferon Beta-1A Administration and Intracranial Vascular Tone Regulation in Patients with Relapsing-Remitting Multiple Sclerosis: A Pilot Study.

Interferon beta (IFN-) therapy is one of the most commonly prescribed immunomodulatory therapies in relapsing-remitting multiple sclerosis (RRMS). A reversible cerebral vasoconstriction syndrome (RCVS), associated with IFN- use, has been recently described. For this reason, we tested the effect of once a week intramuscular administration of IFN--1A on the function of cerebral vessels in a cohort of RRMS patients. Using transcranial Doppler (TCD) ultrasound, we measured the mean blood flow velocity (MFV) in intracranial vessels 10 h after IFN- administration. Measurements showed a significant increase in MFV compared to the baseline values in some vessels.