Incidence and clinical correlation of intracranial hemorrhages observed by 3-tesla gradient echo T(2)*-weighted images following intravenous thrombolysis with recombinant tissue plasminogen activator.

Background: The purpose of this study was to determine the incidence and clinical correlation of intracranial hemorrhages (ICHs) detected by 3-tesla gradient echo T(2)*-weighted images after intravenous recombinant tissue plasminogen activator (rt-PA) administration.

Methods: We included 43 consecutive patients with anterior-circulation ischemia who underwent MRI studies before and after thrombolysis. Each hemorrhage was classified as a hemorrhagic infarction (HI) or parenchymal hemorrhage (PH) according to the European Cooperative Acute Stroke Study definition. The clinical outcome was defined as an improvement (> or =4-point reduction) or deterioration (> or =4-point increase) based on a comparison between the initial and the 30-day NIHSS scores.

Results: The incidence of ICHs was 58%, and the HI rate was 52%; both were higher than the rates reported in the literature. Most of the patients with HI improved clinically, and these patients had second MRAs that showed recanalization. None of the patients with PH demonstrated improvement.

Conclusions: Three-tesla MRI may reveal a higher frequency of HI type hemorrhages than lower-field MRIs, and HI may be a predictor of good recovery by reflecting the presence of recanalization. The rate of PH in our study was low compared to other studies, probably due to the lower dosage of rt-PA.