臨床神経学

第48回日本神経学会総会

<シンポジウム8-2>最新の脳卒中治療
脳梗塞急性期の診断ツールとしてのMRI

五十嵐 博中

新潟大学脳研究所統合脳機能研究センター〔〒951-8585 新潟県新潟市旭町通1-757〕

Goal of initial imaging study for acute-stage ischemic stroke are to detect focal lesion accurately and to assist the therapeutic decision. With the goal in mind, we investigated feasibilities of MRI for acute-stage ischemic stroke.
Firstly, we assessed whether diffusion weighted images (DWI) raised diagnostic accuracy for acute-stage ischemic stroke. We investigated how DWI study changes the diagnosis for the patients with neurological symptom in emergency room. Out of 164 patients who visit the emergency room with neurological symptom, sensitivity, specificity and efficiency for ischemic stroke diagnosis before DWI study were 0.87, 0.85 and 0.89 respectively. DWI raised them to 0.99, 0.98 and 0.99. These result proves feasibility of DWI on diagnosis of acute-stage ischemic stoke.
Secondly, we assess whether DWI and perfusion imaging (PI) can provide any information about fate of acute ischemic lesion. We compared the relationships between DWI and PI parameters (ADC, rCBF, MTT, rCBV) and tissue outcome (infracted or survived). In patients with successful recanalization, best predictor was ADC and the cut-off value was 0.90 against contra-lateral hemisphere. In patients without recanalization, rCBF at 0.66 against contra-lateral hemisphere predicted the pathological fate most accurately. This simple guidepost can be help therapeutic decision of acute-stage stroke.

(臨床神経, 47:921−924, 2007)
key words:脳虚血, 磁気共鳴, diffusion, perfusion

(受付日:2007年5月16日)