Objective:

To assess the feasibility of dual-layer spectral computed tomography (DLCT) derived perfusion parameters as a reliable alternative to conventional cerebral perfusion computed tomography (cCTP), emphasizing patient safety.

Key Findings:

• 39% reduction in radiation exposure for spectral data from single-phase CTA compared to cCTP, which may enhance patient safety in repeated imaging scenarios.
• Good agreement between sCTP and cCTP parameters, particularly at 60 keV VMIs, suggesting reliability in clinical assessments.
• ID maps from DLCT may serve as static surrogates for cCTP imaging, lacking dynamic parameters like CBF or MTT, which is crucial for stroke triage.

Interpretation:

DLCT-based VMI reconstructions can reliably estimate perfusion metrics and may reduce radiation exposure, potentially transforming imaging protocols for patients needing repeated assessments.

Limitations:

• The study included patients with varying diseases and uncertain perfusion status, complicating the assessment of diagnostic performance and introducing potential biases.
• DLCT-derived ID maps do not provide time-resolved perfusion parameters essential for stroke triage, limiting their applicability in acute settings.

Conclusion:

DLCT shows promise in cerebrovascular imaging by providing iodine mapping and potentially reducing radiation exposure, but further validation is needed to establish its role as a true surrogate for dynamic perfusion parameters.