This study aims to assess the impact of CTP acquisition in regional hospitals on quality metrics, functional and safety outcomes in patients with LVO.

The utility of CTP imaging in spoke hospitals to determine eligibility for MT remains controversial. 

Consecutive adult patients treated for LVO after initially presenting to regional spokes between Jan 2021 to Dec 2021 were included. CTP was added to acute stroke imaging protocol in April 2021. Demographics, NIHSS, quality metrics, imaging parameters, and functional outcomes were compared between patients who did vs. did not undergo CTP at a regional hospital. Core volume growth and rate (ml/min) was assessed for patients with CTP data both at the regional and at the CSC. 

CTP studies were performed on 1083 in regional patients and LVO was confirmed in 29 (2.6%) patients. Of these, 14 were transferred to CSC without CTP at the regional and 15 were transferred with CTP at regional hospital. Age (p=0.44), NIHSS (p=0.08), door to thrombolysis (p=0.13), door-in-door-out (p=0.17) times, successful reperfusion (TICI IIb/III; p=0.83) and hemorrhagic transformation (ECASS III; p=0.49) did not differ significantly between the groups. Rates of mRS 0-2 were similar in both groups (p=0.85). In subgroup analysis of patients who underwent CTP both at the regional facility and CSC (n=15), median core volume grew significantly but slowly (0[0, 7] ml vs. 7 [0, 14] ml, p=0.022), at a median rate of 0 [0, 0.07] ml/min. No patients were excluded from thrombectomy due to core growth.

Our study suggests that regional site perfusion imaging does not have a significant impact on process times, quality metrics and outcomes. Core volume grows during interfacility transfers without an impact on eligibility for MT. A larger study is needed to assess the role perfusion imaging in regional spokes.