He was President of the European Neurological Society, Chairman of the Stroke Portuguese Society and member of the Scientific Panel for Health of the Directorate-General for Research and Innovation, Directorate E – Health of the European Commission. He belongs to the Editorial Board of Stroke, European Journal of Neurology, Journal of Neurology, European Stroke Journal and Cerebrovascular Diseases.

Has authored or co-authored 360 papers published in peer-reviewed journals and 60 book chapters. His research interest focuses on cerebrovascular disease, in particular cerebral venous thrombosis. He authored or co-authored 75 publications on cerebral venous thrombosis. He was the coordinator and 1st author or the European ESO-EAN Guidelines for Cerebral Venous Thrombosis and is also co-author of the American AHA/ASA Cerebral Venous Thrombosis Guidelines. He was/is the principal investigator of several multicenter/multinational studies on this disease (VENOPORT; ISCVT; DECOMPRESS1 and 2; EXCOA-CVT; RESPECT-CVT)