Objective: To investigate changes in the cerebrospinal fluid flow in patients with cervical spondylosis using cine phase-contrast magnetic resonance (MR) imaging.
Methods: The participants included 44 healthy volunteers, 11 asymptomatic patients with evidence of degenerative changes of the cervical spine revealed by MR imaging but no neurological symptoms referable to those abnormalities, and 23 symptomatic patients with myelopathy who underwent surgery. Cervical spondylotic myelopathy was evaluated using the Japanese Orthopedic Association scores, and the percentage reduction of the transverse cord area at the level of maximum cord compression was measured on T1-weighted magnetic resonance images. A cine phase-contrast MR pulse sequence with peripheral gating was used to measure the cerebrospinal fluid flow direction and velocity in the ventral subarachnoid spaces at the C1 and T1 levels.
Results: The velocity waveforms produced by plotting flow velocity at 16 intervals during one cardiac cycle significantly differed among the healthy volunteers, asymptomatic patients, and preoperative symptomatic patients. However, velocity waveforms did not differ between the healthy volunteers and the postoperative patients at the C1 level. Decreases of flow velocity were significantly correlated with the severity of myelopathy and the percentage reduction of cord area. Patients with severe myelopathy (Japanese Orthopedic Association score of 0-9 points) or greater than 30% reduction of cord area showed significantly decreased flow velocity compared with those with mild myelopathy (Japanese Orthopedic Association score of 10-17 points) or less than 30% reduction of cord area. Changes in flow velocity were not correlated with multiplicity of the lesion or the level of maximum cord compression. Postoperative improvement of flow velocity was not correlated with neurological recovery.
Conclusion: Cine phase-contrast MR imaging allows quantitative and noninvasive assessment of changes in cerebrospinal fluid flow in patients with cervical spondylosis.