RAPID: A routine assurance pipeline for imaging of diffusion

Abstract

Despite the widespread adoption of diffusion MRI techniques, there is still no consensus on a comprehensive quality assurance routine specific for diffusion acquisitions. We propose here a routine assurance pipeline for imaging of diffusion. The routine simply comprises diffusion-weighted acquisitions on a phantom; each repetition lasts less than 5 min and can be performed using a variety of isotropic test liquids. The proposed QA script checks for the linearity of G, the uniformity of G max across the field-of-view, the mutual agreement of gradient power across the three logical axes and the temporal stability. Optionally, the routine can correct for the mutual agreement of gradient power along the three axes, returning a set of gradient orientations to be used in data analysis. The effectiveness of the scheme in the presence of mismatched gradient amplitudes is reported using both simulations and in vivo data. The script is freely available online.

Technical Note: A safe, cheap, and easy‐to‐use isotropic diffusion MRI phantom for clinical and multicenter studies

“…DTI quality assurance scans on the Sokalan phantom, in line with: 12 diffusion directions at five different b‐values (350, 700, 1050, 1400 and 1750 s/mm 2 ), with 2 mm and 3 mm isotropic resolution, on scanners A and B, a Siemens Magnetom Skyra 3T with a 20 channel head/neck coil, as well as a clinical DTI scan on the Sokalan phantom with 30 diffusion directions and b = 1000 s/mm 2 , 2 mm resolution, on scanner A and scanner B. On scanner B, we also did an experiment with the phantom facing the wrong direction, as might happen by accident, to see if this makes a difference in measured ADC values.…”

Quality assurance multicenter comparison of different MR scanners for quantitative diffusion-weighted imaging

“…Only a few studies have addressed multicenter systematic comparisons of quantitative DWI by means of phantom measurements . Also, there is a lack of standardized DWI quality assurance procedures, as pointed out previously …”

A novel DTI-QA tool: Automated metric extraction exploiting the sphericity of an agar filled phantom

“…Previous automated phantom-based QA approaches have focused primarily on the ability of the diffusion sensitizing gradients to perform as expected, measuring accuracy, repeatability and precision of ADC/FA measurements in a variety of isotropic phantoms. These methods offer gradient calibration routines [9] and other calibration metrics for multicentre studies [10–12]. Here, we present a phantom-based, automated quality assurance (QA) tool which incorporates both the assessment of artifacts and distortions present in DTI data, while measuring the performance of the diffusion sensitizing gradients as well.…”