A phantom approach to interscanner comparability of computed tomographic brain perfusion parameters

Area of Science:

• Medical Imaging
• Radiology
• Biomedical Engineering

Background:

• Computed tomography (CT) perfusion imaging is crucial for assessing brain perfusion.
• Reproducibility in CT perfusion experiments is essential for reliable clinical application.
• Variability in experimental factors can impact perfusion parameter accuracy.

Purpose of the Study:

• To develop a novel perfusion phantom for reproducible CT perfusion experiments.
• To investigate the impact of contrast bolus configuration, scan parameters, and scanner hardware on perfusion calculations.
• To enhance the understanding of factors influencing CT perfusion measurement accuracy.

Main Methods:

• A discoid perfusion phantom with controlled flow was engineered.
• Inert polyoxymethylene spheres simulated brain parenchyma.
• Multiple measurements were conducted, varying key experimental factors for analysis.

Main Results:

• Experimental flow measurements demonstrated high reproducibility and strong correlation with true flow (R = 0.995).
• Factors such as tube voltage, contrast injection rate, perfusion algorithm, and scanner hardware reproducibly influenced calculated perfusion results.
• The developed phantom proved effective in a controlled experimental setting.

Conclusions:

• Perfusion phantoms are valuable tools for standardizing CT perfusion assessments.
• These phantoms can help identify hardware-specific and protocol-related influences across different CT scanners.
• Improved comparability between scanners and protocols can be achieved through phantom-based validation.