Flat-panel detector CT to assess intracranial hemorrhage immediately following mechanical thrombectomy

The risk of symptomatic intracranial hemorrhage (ICH) approaches 5% despite mechanical thrombectomy (MT) efficacy for ischemic stroke secondary to large vessel occlusion. Flat-panel detector CT (FDCT) imaging with Syngo Dyna CT imaging (Siemens Medical Solutions, Malvern, PA) can be used immediately following MT to detect ICH.

To evaluate the accuracy and reliability of FDCT imaging with Dyna CT compared to conventional post-MT CT and MRI.

Head FDCT (20 second, 70 kV) was performed immediately following MT on 26 consecutive patients; postprocedural CT or MRI was obtained ∼24 hours later. Two blinded, independent neuroradiologists evaluated all imaging, identifying ICH, stroke, and presence of subarachnoid contrast. Cohen's κ statistic was used to assess interrater agreement for each imaging outcome and compared the FDCT to conventional imaging.

FDCT for ICH demonstrated a strong degree of interrater reliability (κ = 0.896; 95% confidence interval [CI], 0.734-1.057). Negligible reliability was seen for ischemia determination on immediate post-MT FDCT (κ = 0.149; 95% CI, -0.243 to 0.541). ICH evaluation between FDCT and post-MT conventional CT revealed modest interrater reliability (κ = 0.432; 95% CI, -0.100 to 0.965), which did not reach statistical significance. There was no substantive reliability in the evaluation of ICH between FDCT and post-MT MRI (κ = 0.118, 95% CI, -0.345 to 0.580).

FDCT, such as Dyna CT, immediately post-MT is a promising tool that can expedite the detection of ICH with a high degree of reliability, although the detection of ischemic parenchymal changes is limited.