How to differentiate intracranial atherosclerotic disease or vasospasms after mechanical thrombectomy. Be patient or vasodilator is the secret?

Here we describe a successful mechanical thrombectomy (MT) for acute large vessel occlusion in stroke treatment with one passage (thrombolysis in cerebral infarction, TICI 3). Immediately after the withdrawing of the stent retriever, a narrowing of the middle cerebral artery was diagnosed. The rate of vasospasms during this procedure can be as higher as 41% (range from 6-41%). Here we describe our protocol when a narrowing of the artery is visualized after a stent retriever is withdrawn. A patient presented in our emergency room with National Institute of Health Stroke Scale (NIHSS) of 21, Alberta Stroke Program Early CT Score (ASPECTS) 8, computed tomography angiography revealed occlusion of the M1 segment and MT was indicated. One passage TICI Ⅲ was achieved. After that, the image showed a narrowing of the artery. We present one case of a spasm after stent retriever technique for MT, we injected vasodilator and the artery became normal in a few minutes differentiating between atheromatous stenosis and vasospasm. We present a technical note that can help to make the differentiation of vasospasm or atheromatous disease after MT with the stent retriever technique.