Helmut Rumpel, Presenter: Nothing to Disclose

Yi Chong, Abstract Co-Author: Nothing to Disclose

David A Porter, Abstract Co-Author: Employee, Siemens AG

Ling Chan MBBS, Abstract Co-Author: Nothing to Disclose

We report our experience in examining the ADC values of benign and metastatic vertebral fractures using readout-segmented echo-planar-imaging (EPI) and 1H MR spectroscopy.

Patients with clinically known metastatic or benign vertebral compression fractures were included in this study. The MR protocol at 1.5T consisted of (a) 1H MR spectroscopy (TR/TE/NEX 3000/30/4). Peak areas for water and total lipid were determined from a non-cubic 2.25ml voxel in the centre of the vertebra, and (b) sagittal readout-segmented EPI with 2D navigator correction (FOV 300 mm, matrix 150 X 150, 3 slices, 7.5 mm slice thickness, 9 readout segments per image, one scan at b = 0 s/mm2 and three at b = 650 in orthogonal direction, 4 averages.) The ADC values were analyzed. A spine matrix coil as posterior coil together with a body matrix coil enabled parallel imaging.

The quality of readout-segmented EPI was good with regard to susceptibility based image distortions, artifacts, and reduced T2* blurring effects, which are often seen on single-shot spinal EPI. ADC values of < 1.8x10-3 mm2/s for metastatic (n=12) and > 2.5x10-3 mm2/s for benign (n=8)vertebral compression fractures were found. In the latter, the vertebral collapses were severe, and the lipid fractions were miniscule (<20%). In contrast, partial benign compression fractures (n=6) showed higher lipid fractions of > 20% and non-uniform ADC values were seen across the vertebrae.

Readout-segmented diffusion-weighted EPI is clinically robust and reduces image distortions and artefacts in spine imaging. Benign and metastatic vertebral compression fractures can be differentiated with a high level of confidence based on ADC analysis and 1H MR spectroscopy if the vertebral collapse is severe and the lipid content is low, i.e. lipids may be squeezed out through the veins as a result of pressure during the collapse of the affected area.

Readout-segmented diffusion-weighted EPI and 1H MR spectroscopy may aid in differentiating benign from metastatic vertebral compression fractures.

Rumpel, H, Chong, Y, Porter, D, Chan, L, Readout-Segmented Echo-Planar Diffusion-weighted MRI and 1H MR Spectroscopy in Benign and Metastatic Vertebral Compression Fractures.  Radiological Society of North America 2010 Scientific Assembly and Annual Meeting, November 28 - December 3, 2010 ,Chicago IL. http://archive.rsna.org/2010/9013164.html