In the recent article by Packard et al,1 the authors suggest that an alternative to computed tomography (CT) such as magnetic resonance (MR) imaging should be considered in patients with acute ischemic stroke to lower the risk of an undetected intracerebral hemorrhage, especially if considering thombolytic therapy or anticoagulation. This may be misleading.
Routine spin echo T1- and T2-weighted MR imaging sequences have proved to lack sensitivity and specificity in the setting of hyperacute ischemic stroke.2 On the other hand, spin echo diffusion-weighted MR imaging (DWI) has a better sensitivity than CT for the detection of ischemic stroke.3- 5 Recent studies comparing CT with MR imaging in the setting of acute ischemic stroke have demonstrated that the addition of DWI to conventional MR imaging improves the accuracy of identifying acute ischemic brain lesions in patients who have experienced a stroke. However, these studies enrolled patients later than 3 hours after the onset of symptoms.3,6,7 Considering the strict guidelines for recombinant tissue-type plasminogen activator administration, a patient undergoing DWI-MR imaging in this setting will not be a candidate for emergent thrombolysis.8 Moreover, no data support the benefit of heparin, low-molecular-weight heparin, or warfarin administration in the event of acute ischemic stroke.9,10
Rincon F. Anticoagulation and Thrombolysis for Acute Ischemic Stroke and the Role of Diagnostic Magnetic Resonance Imaging. Arch Neurol. 2004;61(5):801-802. doi:10.1001/archneur.61.5.801-d