Low-Field MR Imaging of the Spine

Abstract

Purpose:

To evaluate a new steady-state sequence in the delineation of the various structures in the spine at low-field MR imaging with a very high homogeneity of the main field.

Methods:

49 patients underwent 53 examinations with both a traditional T1-weighted gradient-echo (PS) sequence and a new completely balanced steady-state 3-D (CBASS3D) sequence; 20 examinations included the cervical spine, 8 the thoracic spine and 25 the lumbar spine. All 106 examinations were reviewed twice regarding visibility of selected structures in the spinal region and diagnostic usefulness.

Results:

The CBASS3D sequence delineated the medulla, nerve roots, CSF, the intervertebral discs and the posterior longitudinal ligament significantly better than the PS sequence. Disc hernia was also better visualised (p<0.01). There were significantly more artefacts on images obtained with the CBASS3D sequence, but they were usually outside the region of interest and occurred less frequently over time due to increased experience of the staff. Both reviewers found the diagnostic usefulness of CBASS3D to be superior compared to that of PS and excellent for diagnostic purposes.

Conclusion:

The CBASS3D sequence is a considerable improvement in the visualisation of degenerative changes of the spine at low-field MR imaging.