Physiopathological implications of abnormal Arterial Spin Labeling perfusion in thrombotic microangiopathy

ABSTRACT Thrombotic microangiopathies are a group of clinical syndromes characterized by microangiopathic hemolytic anemia, thrombocytopenia and end-organ damage, which can compromise the central nervous system. Given the fluctuating nature of the neurological symptoms, conventional brain imaging may be normal. The aim of this report is to describe a 76 years old woman with history of Rheumatoid Arthritis presenting fluctuating aphasia and right hemiparesis secondary to thrombotic microangiopathy, in whom, Arterial Spin Labeling technique revealed increased cerebral blood flow in the left hemisphere despite the absence of acute ischemic lesions. Arterial spin labeling is a magnetic resonance imaging sequence that generates cerebral blood flow maps with no need of tracer injection into the bloodstream. This case suggests that this sequence is useful in the evaluation of neurological symptoms due to thrombotic microangiopathies, since it provides valuable information about alterations in cerebral microcirculation. We discuss the potential physiopathological implications.