Multiple cerebral microbleeds in hyperacute XXXX : impact on prevalence and severity of early hemorrhagic transformation after thrombolytic treatment.

@entity1 @entity1779 @entity548 @entity385
OBJECTIVE: The purpose of our study was to assess whether cerebral microbleeds are related to early hemorrhagic transformation after thrombolytic therapy for hyperacute @entity385 . MATERIALS AND METHODS: The cases of 279 @entity1 with suspected @entity385 who underwent MRI including T2*-weighted images were retrospectively evaluated. The inclusion criteria were as follows: imaging performed within 6 hr after symptom onset, presence of territorial infarct of anterior circulation, no history of @entity1779 , thrombolytic treatment, and available follow-up MR images. Microbleeds were classified according to number as follows: absent (grade 1, 0 @entity548 ), mild (grade 2, 1-2 @entity548 ), moderate (grade 3, 3-10 @entity548 ), and severe (grade 4, > 10 @entity548 ). The prevalence and severity of early hemorrhagic transformation after thrombolysis were assessed on follow-up images. RESULTS: Among 279 @entity1 , 65 @entity1 (37 @entity1 , 28 @entity1 ; mean age, 67 years) met the inclusion criteria. Microbleeds were found in 25 @entity1 . Early hemorrhagic transformation occurred in nine of 40 @entity1 without microbleeds (grade 1) and in eight of 25 @entity1 with microbleeds: two of 12 @entity1 with grade 2, three of eight @entity1 with grade 3, and three of five @entity1 with grade 4 microbleeds. The presence of symptomatic @entity548 did not correlate with the number of microbleeds. Results of multivariate logistic regression analysis showed that the presence of microbleeds was not associated with hemorrhagic transformation after thrombolytic treatment. CONCLUSION: Small and large numbers of microbleeds are not independent risk factors for early hemorrhagic transformation and symptomatic @entity548 after thrombolytic therapy for hyperacute @entity385 . Additional studies with large groups of subjects are needed to confirm our conclusion.
