Exploring the role of CT scouts in expediting MRI in acute stroke

For acute stroke patients requiring MR examination and unable to provide a reliable history, screening for potentially MRI-incompatible objects (PMIOs) typically necessitates the use of plain-film radiographs (PFRs). However, using a whole body CT scout at the time of non-contrast head CT scans can preclude critical delays. Here, we aim to compare the effectiveness of PFRs and CT scouts in detecting PMIOs.

A case-control study was conducted at a tertiary care institution, involving 408 imaging studies from 200 patients, half of which contained PMIOs. The diagnostic performances of CT scouts and PFRs were evaluated by six blinded readers, including two board-certified neuroradiologists, one neuroradiology fellow, and three radiology residents.

2448 interpretations from the 6 readers were analyzed. The diagnostic performance of combined CT scout images (full-body and regional) was not significantly different from that of PFRs for all six readers (p = 0.06). However, PFRs outperformed full-body CT scouts in PMIO detection (p = 0.01), with no significant differences observed between PFRs and regional CT scouts (p = 0.4). Notably, the diagnostic accuracy of the radiology residents was found to be equivalent to radiologists across all imaging techniques.

Integrating CT scouts in acute stroke protocols may help expedite MRI screening. The scouts should include the head, neck, chest, upper arms, abdomen, pelvis, and thighs. Including radiology residents in the screening process for PMIOs may be an avenue for resource optimization in acute care settings.