Scoring of Middle Cerebral Artery Collaterals Predicts RAPID CT-Perfusion Analysis and Short-Term Outcomes in Acute Ischemic Stroke Patients Undergoing Thrombectomy.

OBJECTIVE: The rapid processing of perfusion and diffusion (RAPID) system for automating perfusion and diffusion data from head computed tomography has improved acute ischemic stroke treatment by quickly and accurately identifying those patients who may benefit from thrombectomy. Collateral scoring (CS) of cerebral arteries using computed tomography angiography (CTA) has proven useful in predicting postintervention infarct volumes and functional outcomes in ischemic stroke patients. Here we evaluate the relationship between CS and RAPID software in an effort to augment triage and provide improved predictability of functional outcomes in ischemic stroke patients. METHODS: A retrospective review of 77 mechanical thrombectomy patients from January 2017 to October 2018 with large vessel occlusions of the anterior circulation who underwent RAPID and CTA imaging was performed. Baseline characteristics, RAPID data, CS, modified Rankin Scale score, and procedural data were collected. magnetic resonance imaging was used to calculate the postintervention stroke volume. RESULTS: CS inversely correlates with the volume of RAPID cerebral blood flow <30% (ß= -18.131, 95% confidence interval [CI] -24.384 to -11.879, P < 0.001), RAPID Tmax >6s (ß= -22.205, 95% CI -39.125 to -5.285, P = 0.011), postintervention stroke volume (ß= -30.637, 95% CI -41.554 to -19.720, P < 0.001), and discharge National Institutes of Health Stroke Scale score (ß= -1.922, 95% CI -3.575 to -0.269, P = 0.023). CONCLUSIONS: CS on CTA may be a useful way to identify patients who would benefit from mechanical thrombectomy and predict functional outcomes postintervention. CS may allow the stroke team to optimize the care of patients who may not be able to obtain RAPID analysis.