QUASAR™ MRID3D is a new, patent pending, cost-effective QA system for quantifying geometric distortion in 3D MR images. Analysis is performed on images for diagnostic and guidance applications.

Unlike other distortion analysis products, which only sample a few imaging planes, the QUASAR™ MRID3DGeometric Distortion Analysis System analyzes the entire 3D field of view in a single acquisition.

The system, based on the harmonic analysis method, uses 3D Laplace Partial Differential Equations to map the 3D Distortion Vector Field by analyzing the Boundary Distortion Vector Field derived from the location of known control points on the surface of the phantom. The large, lightweight phantom is easy to setup in MRI scanners and comes with quick and easy-to-use image analysis software.

A submission to Medical Physics is available online: A Harmonic Field Approach to Quantifying MRI Spatial Accuracy for MRIgRT. The results have been verified by comparison to a custom high density 3D grid phantom.

Key Features

  • Novel method based on 3D harmonic analysis of distortion
  • Uses 3mm fiducials as per MS 12-2010 recommended NEMA standards for measuring the absolute spatial variation of geometric accuracy within MR images
  • Quantify, in full 3D, the geometric distortion of MR images
  • Highly refined and robust control point finder algorithm able to correctly identify targets at very high bandwidths and low SNR, as well as very low bandwidths and high distortion or with no vendor distortion correction applied
  • Fast T1 weighted 3D isotropic GRE scans can be acquired in as little as 5 minutes at 3T, 10 minutes at 1.5T
  • Rich set of data analysis tools: histograms, cumulative distortion plots, interactive axial plots of X, Y, Z distortion magnitude vs Z position
  • Powerful 3D visualization toolkit with ROI (sphere, cube) analysis, synthetic grid, 3D Distortion Vector Fields, Boundary DVF Colour Plot, 3D Manual DVF Probe
  • Separate plots for gradient nonlinearity distortion and B0 inhomogeneity distortion when data is acquired with two opposite polarity frequency encode scans
  • Export function includes entire 3D DFV in csv format plus automated QA pdf reports
  • Trending Analysis; Compare machines and/or sites
  • Designed for MR image guidance and diagnostic imaging
  • Large field of view (37cm diameter x 32cm long)
  • Light weight phantom (21 kg compared to 40 - 80 kg conventional phantoms)
  • System includes automated image analysis software
  • Future insert accessory option for Image Quality, Dosimetry, and ACR phantoms

This page was printed from OSL Web site at http://www.osl.uk.com