PerfusieCTMR

PerfusieCTMR is a multimodal imaging concept that combines perfusion data acquired with computed tomography (CT) and magnetic resonance imaging (MRI) to characterize tissue hemodynamics. It may be implemented on hybrid CT-MR systems that can perform CT perfusion (CTP) and MR perfusion in a single examination, or through sequential CT perfusion and MR perfusion studies with subsequent image fusion and co-registration to a common space.

CT perfusion measures dynamic iodinated contrast passage to estimate cerebral blood flow (CBF), cerebral blood volume (CBV), and mean transit time (MTT) or Tmax. MR perfusion uses dynamic susceptibility contrast (DSC) or dynamic contrast-enhanced (DCE) methods, or arterial spin labeling (ASL) to derive similar parameters. Differences in sensitivity, spatial resolution, and acquisition times are typical between the modalities.

Potential advantages include complementary information: CT provides rapid acquisition and high spatial resolution; MR yields superior soft tissue contrast and additional functional data. In stroke, perfusieCTMR can help delineate infarct core and penumbra, while in brain tumors it can inform vascularity and treatment response.

Limitations include increased contrast load and radiation exposure, longer exam times, the need for expertise in image processing, potential contraindications to gadolinium-based agents, and cost. Standardization of acquisition protocols and interpretation remains an area of ongoing research.