MRI foci of signal loss: A possible indication of increased risk for intracerebral haemorrhage

Magnetic resonance imaging (MRI) of the brain using T-2*-weighted sequences detects focal areas of signal loss in about half of patients with primary intracerebral haemorrhage. These lesions were histopathologically confirmed to represent residues of previous, clinically silent microbleeds and are a consequence of various vasculopathies with hypertensive lipofibrohyalinosi s as the leading cause. When associated with cerebral amyloid angiopathy fo ci of signal loss tend to be located primarily at cortico-subcortical sites . Most importantly old microbleeds can also be detected in patients with is chemic vascular diseases and rarely even in the healthy elderly population. Possibly predicting a higher risk for intracerebral hemorrhage in such per sons this finding could therefore influence therapeutic decisions regarding the use of agents which increase the likelihood of bleeding. This hypothes is will have to be tested in prospective trials. Already now MRI evidence o f microbleeds has some diagnostic relevance for patients with an intracereb ral hematoma because of the etiologic implications of this observation.