A stepless, pneumatically operated motion apparatus for the dynamic MRI of the cervical spine.

Purpose: To develop and evaluate a new, pneumatically operated motion apparatus for the dynamic functional MR examination of the cervical spine. Materials and Methods: A metal-free, pneumatically operated motion apparatus for functional dynamic MR imaging of the cervical spine was developed with respect to the geometry of a short-bore, superconducting high-field MR system. The examination protocol included a T-2-weighted multi-slice turbospin echo sequence (T-2-TSE, TR/TE = 2610/115, matrix 254/512) and a dynamic T-2-weighted single-shot sequence (T-2-TSE, TR/TE = 1110/110, matrix 255/256, acquisition time 1 s) in a sagittal plane. In order to evaluate the new motion apparatus and the examination protocol, 10 healthy subjects and 10 patients were examined. Results: The new motion apparatus allowed us to perform a passive stepless inclination and reclination motion of the patient's cervical spine within the MR scanner without leaving the magnet bore. The maximum motion degrees of the cervical spine were within -35 degrees (reclination) and 30 degrees (inclination). Due to the T-2-contrast and the high spatial resolution of the dynamic sequence, the myelon, the surrounding cerebrospinal fluid and the discoligamental structures were imaged with a good contrast and allowed a sufficient evaluation of the cervical spinal channel in all functional positions. Conclusions: This new motion apparatus allows a standardized and stepless dynamic functional MR examination in a short-bore high-field MR scanner. By the use of fast T-2-weighted spin echo sequences it has been shown to be of high value for the evaluation of the cervical myelon, the anterior and posterior cerebrospinal fluid and the discoligamental structures.