Between-Scanner and Between-Visit Variation in Normal White Matter Apparent Diffusion Coefficient Values in the...

Area of Science:

• Radiology
• Neuro-oncology
• Medical Imaging

Background:

• Glioblastoma multiforme (GBM) requires consistent imaging for clinical trials.
• Apparent diffusion coefficient (ADC) measurements are sensitive to imaging parameters.
• Multi-center trials necessitate understanding between-scanner and between-visit variability.

Purpose of the Study:

• To assess between-scanner variation in brain ADC measurements.
• To evaluate between-visit reproducibility of ADC in a multi-center GBM trial.
• To identify factors influencing ADC measurement consistency across different scanners and visits.

Main Methods:

• Calculated ADC maps from diffusion-weighted images from 52 patients across six sites.
• Utilized seven scanner models from two vendors with varying magnetic field strengths.
• Analyzed median ADC and coefficient of variation (CV) in normal white matter regions of interest.

Main Results:

• No significant difference in baseline median ADC across scanner models, vendors, or magnetic fields.
• Significant differences in baseline ADC CV were observed between scanner models (p=0.0002).
• No between-scanner differences in ADC changes between visits, but significant differences in ADC values between successive visits for the whole group.

Conclusions:

• Scanner variability, likely due to image noise, significantly impacts ADC coefficient of variation.
• Consistent scanner parameter setup is crucial for improving the reproducibility of ADC measurements between visits.
• Standardized imaging protocols are recommended for multi-center glioblastoma trials using ADC measurements.