Reversibility of ischemic findings on 3-tesla magnetic resonance T2^*-weighted image after recanalization

Abstract

Ischemic vessel signs (IVS) can be detected on 3-tesla T2^*-weighted magnetic resonance images as a vessel enlargement at the territory of acute ischemia caused by major vessel occlusion or stenosis. Here, we studied changes in IVS before and after recanalization by the administration of intravenous recombinant tissue plasminogen activator (IV rtPA), carotid artery stenting or percutaneous transluminal angioplasty in patients with major vessel occlusion or stenosis. We performed magnetic resonance imaging for all patients treated by IV rtPA at the time of admission, shortly after and 24-72 hours after treatment with IV rtPA. We reviewed the IVS to assess its natural course of IVS by assessing patients who did not recanalize. IVS tended to disappear after recanalization. Conversely,in patients without recanalization, IVS did not disappear shortly after IV rtPA; rather, it disappeared 24-72 hours after IV rtPA, especially in the presence of complete infarction. Recanalization by IV rtPA or endovascular treatment contributed to improved clinical deficits or the prevention from further progression. IVS can be a parameter of misery perfusion and an important factor to detect the patients who have an indication of treatment for recanalization. J. Med. Invest. 61: 190-196, February, 2014