Purpose Multiphase CTA (MCTA) has recently been advocated as an acceptable alternative to whole brain CT perfusion (CTP) for identifying patients with intracranial large vessel occlusion (LVO) who may benefit from thrombectomy (1). Our institution recently transitioned from CTP to MCTA for triage of acute stroke patients. The purpose of this study is to identify predictors of collateral scores and evaluate the likelihood of undergoing intervention based on these scores.

Materials and Methods The imaging database was queried for all patients who underwent MCTA from August 2016 through March 2017. Rates and locations of large vessel occlusions, collateral scores, rates of thrombectomy, and TICI scores were reviewed. Several comorbidities/risk factors were reviewed.

Results 84 out of 238 patients who underwent MCTA were found to have intracranial LVO, with 48 patients subsequently undergoing thrombectomy. Table 1 shows rates of thrombectomy by collateral score. Risk factor analysis showed that patients who were transferred had a statistically significant likelihood of having poor collateral scores (p=0.018).

Conclusion Collateral scores of 4 and 5 have over 80% rate of inclusion for thrombectomy in the setting of a large vessel occlusion. Transfer of patients is correlated with statistically significant poorer collateral scores.

Reference

1. . Menon BK, d’Esterre CD, Qazi EM, et al. Multiphase CT Angiography: A New Tool for the Imaging Triage of Patients with Acute Ischemic Stroke. Radiology2015May; 275(2):510–20

Disclosures G. Bennett: None. S. Arndt: None. J. Lavie: None. A. Albar: None. G. Vidal: 3; C; Penumbra. J. Milburn: 3; C; Penumbra.