Computed Tomography Perfusion-Based Decision Making for Acute Ischemic Stroke-Missing the Mismatch

The emerging use of mechanical thrombectomy for acute ischemic stroke treatment focuses on the importance of patient selection. Computed tomography perfusion (CTP) is one of widely used techniques. However, the accuracy and reliability of this modality is in debate among vascular neurologists. We present a case of an 80-year-old man admitted because of acute ischemic stroke. CT angiography demonstrated left proximal M2 occlusion. As CTP demonstrated signs of large ischemic core with no significant penumbra, mechanical thrombectomy was not performed following tPA administration. Twenty-four hours after thrombolysis, the patient was neurologically intact. Both non-contrast CT and magnetic resonance imaging (MRI) demonstrated small stroke involving the left caudate. Differences between CTP and MRI diffuse-weighted imaging were previously described. However, in the presented case, these differences were brought to extreme, precluding endovascular treatment. In our opinion, this case emphasizes why CTP should not be used for patient exclusion among patients in the early time frame for intervention. Such patients should be evaluated by MRI or by clinical-radiological mismatch only. CTP may have a role in selecting patients for endovascular intervention in borderline circumstances such as prolonged time window, wake-up stroke, etc.