Do pretreatment MRI scoring systems affect the safety and efficacy of thrombolytic therapy for acute ischemic stroke?
Six studies were identified that addressed the effectiveness of an MRI scoring system for ischemic stroke. One multiple prospective cohort study8 and one single prospective cohort study,9 published in 2002 and 2003, were included in our review. Three non comparative case series reports10-12and one case study were excluded for level of evidence.13 Neither of the included studies used MRI measures prospectively to make decisions on thrombolysis. Both, however, provided correlations with surrogate measures which may be useful in clinical decision making. Recanalisation and initial DWI lesions were found to correlate with clinical outcome and infarct volume at 60 days. In addition, in patients treated with intravenous tPA, time to peak was correlated with recanalisation at day 1. Thirteen of 15 patients (93%) whose baseline time-to-peak was less than or equal to 36.9 milliseconds recanalized within the first day versus 5 of 15 patients (35.7%) whose time-to-peak was greater than 36.9 milli