Apparent Diffusion Coefficient Value Is Not Dependent on Magnetic Resonance Systems and Field Strength Under Fixed...

Area of Science:

• Radiology
• Medical Imaging
• Diffusion MRI

Background:

• Apparent diffusion coefficient (ADC) measurements are crucial for diagnosing brain conditions.
• Variability in ADC values across different magnetic resonance (MR) scanners and vendors can lead to diagnostic errors.
• Standardizing ADC measurement protocols is essential for reliable clinical interpretation.

Purpose of the Study:

• To identify causes of ADC measurement errors in MR imaging.
• To determine optimal scanning parameters for consistent ADC measurements.
• To achieve ADC values independent of MR system field strength and vendor.

Main Methods:

• Brain MR images were acquired from 10 healthy volunteers using 6 MR scanners (different field strengths and vendors).
• Coefficient of variation (CV) of ADC values was analyzed across scanners and subjects.
• Intrascanner and intersubject variability were compared.

Main Results:

• The overall CV of ADC values across 6 scanners was 3.32%.
• Intrascanner CV for repeated measurements was low (1.72% daily, 2.96% over 10 days).
• Intersubject CV was 5.22%, indicating higher variability between individuals than between scanners with optimized parameters.

Conclusions:

• ADC measurement variance across different MR scanners is minimal with appropriate parameters.
• Optimal parameters include repetition time >3000 ms, minimum echo time, and high SNR diffusion-weighted images.
• Standardized scanning protocols can significantly reduce ADC measurement errors.