Normalization of temperature effects for quality assurance of quantitative prostate apparent diffusion coefficient...

Area of Science:

• Magnetic Resonance Imaging
• Medical Physics
• Prostate Cancer Imaging

Background:

• Apparent Diffusion Coefficient (ADC) in diffusion-weighted imaging correlates with prostate tumor aggressiveness.
• Variability in ADC measurements across scanner networks necessitates quality assurance (QA) for prostate MRI protocols.
• Traditional ADC reproducibility assessments require strict 0°C phantom temperature control, posing a logistical challenge.

Purpose of the Study:

• To establish a room-temperature QA procedure for assessing the reproducibility of ADC measurements in prostate diffusion MRI.
• To develop a model correlating ADC, phantom gel concentration, and temperature for accurate normalization.

Main Methods:

• Diffusion phantom imaging across multiple 1.5T and 3T scanners at different locations.
• ADC measurements were taken at varying phantom gel concentrations.
• A temperature-dependent ADC model was applied to normalize measurements to a reference temperature (20°C).

Main Results:

• Temperature normalization reduced the variability (percent difference) in ADC measurements across scanners.
• The coefficient of variation (CV) for clinically relevant ADC values decreased from 5.0% to 3.4% post-normalization.
• The CV for pure water ADC decreased from 3.3% to 1.3% after normalization.

Conclusions:

• A novel QA procedure utilizing a temperature model eliminates the need for strict phantom temperature control.
• This method facilitates reliable ADC reproducibility assessments for prostate diffusion MRI across extensive scanner networks.
• The developed QA procedure enhances the consistency and accuracy of quantitative ADC measurements in multi-center studies.