Association between intracranial arterial shear rate and neurological outcomes in acute middle cerebral artery occlusion and recanalization

초록

Background and aims: Shear rate is a hemodynamic marker of vascular health. The signal intensity gradient (SIG), derived from time-of-flight (TOF-MRA), serves as an indirect marker for shear rate. We investigated the association between cerebral artery SIG and outcomes in patients with acute middle cerebral artery (MCA) occlusion who underwent reperfusion therapy. Methods: Patients with a major intracranial artery occlusion and successful recanalization via intravenous (IV) thrombolysis and/or endovascular therapy (EVT) from seven university hospitals in South Korea (2017–2023) were enrolled. The TOF-MRA were examined at pre- and post-recanalization stages. Cerebral artery SIG and radius were analyzed with clinical outcomes including NIHSS, mRS, and early neurological deterioration (END). As a marker of clinical improvement, an NIHSS ratio, NIHSS score (arrival - discharge)/arrival, ≥ 70 % was defined as a neurologic improvement. Results: Among 105 patients, 4 patients (3.8 %) underwent IV thrombolysis, 72 (68.6 %) EVT, and 29 (27.6 %) IV and EVT, respectively. The SIG and radius of lesion-sided internal carotid artery (ICA) C1 segment, MCA M1, and anterior cerebral artery (ACA) A1 were significantly lower and smaller than the contra-lesional values. For the neurological improvement, women, atrial fibrillation, END, and ACA A1 SIG lesion-to-contralesional ratio showed independent associations. Conclusions: For patients with an acute MCA occlusion, the SIG ratio of A1 segment in the pre-recanalization MRA is significantly associated with neurologic improvement. The lesion-sided A1 segment of ACA might serve as an important channel for collateral circulation in the acute stage of MCA occlusion, and SIG might be useful to predict clinical outcomes.