Perfusion-Based Decision-Making for Mechanical Thrombectomy in a Transient Ischemic Attack Patient with Middle Cerebral Artery Occlusion.

A significant proportion of patients with large-vessel occlusion (LVO) initially present to the hospital with transient ischemic attack (TIA) and mild clinical manifestations such as low National Institutes of Health Stroke Scale (NIHSS) scores (≤5). However, due to the natural course of the disease, the individuals may subsequently develop worsening symptoms. To date, there is lack of evidence-based guidelines on mechanical thrombectomy (MT) among those patients. Therefore, the predicting factors associated with better or worse outcomes for acute stroke patients receiving MT compared to those not receiving the treatment are unknown. We describe a TIA case with LVO who was treated with MT; we used perfusion imaging as a decision aid. A 55-year-old male patient with a past medical history of TIA, hypertension, and hyperlipidemia was admitted to our hospital for evaluation of transient mild right hemiparesis and dysarthria lasting for 5 min 3 h before admission. He reported that he had experienced the same condition 1 day before. On admission, neurological examination showed normal function with an NIHSS score of 0. Computed tomography angiography revealed left proximal M1 occlusion. In addition, perfusion magnetic resonance imaging maps calculated by the RAPID software showed acute small lesions on the left hemisphere with core volume (0 mL) and a large ischemic penumbra (70 mL). Immediate endovascular thrombectomy was performed 5 h following symptom onset with complete recanalization and clinical recovery. The case suggests that MT in LVO patients with low NIHSS scores, even a score of 0, on presentation is potentially a safe and effective treatment. The use of perfusion imaging in the acute phase of stroke should be encouraged for the decision-making process.