A linear mixed perfusion model for tissue partial volume correction of perfusion estimates in dynamic susceptibility...

Area of Science:

• Neuroimaging
• Medical Physics
• Radiology

Background:

• Partial volume effects (PVE) introduce significant bias in brain perfusion measurements.
• The impact of tissue PVEs on dynamic susceptibility contrast MRI (DSC-MRI) perfusion measurements requires further investigation.
• Accurate brain perfusion quantification is crucial for diagnosing and monitoring various neurological conditions.

Purpose of the Study:

• To propose and evaluate a partial volume correction (PVC) method for DSC-MRI.
• To assess the influence of PVC on DSC-MRI derived perfusion parameters.
• To quantify the reduction in tissue volume dependence of perfusion measurements after PVC.

Main Methods:

• A linear mixed perfusion model for DSC-MRI was developed and validated using simulations.
• Twenty healthy volunteers underwent repeated DSC-MRI, arterial spin labeling (ASL), and partial volume measurements.
• Two distinct PVC algorithms were implemented and compared for their efficacy.

Main Results:

• Simulations indicated an overestimation of perfusion values in voxels with high cerebrospinal fluid fractions without PVC.
• PVC substantially reduced tissue volume dependence, from 44.4% to 4.2% in gray matter and 55.3% to 14.2% in white matter.
• One PVC method improved voxel-wise repeatability, though spatial agreement with ASL perfusion maps was not enhanced.

Conclusions:

• Significant partial volume effects impact DSC-MRI perfusion estimates.
• The developed PVC approach effectively mitigates these PVEs in DSC-MRI.
• PVC is a critical consideration for improving the reliability and accuracy of DSC-MRI applications.