Objective: To evaluate the new magnetic resonance imaging (MRI) method of dynamic MRI with fast imaging in the diagnosis of sacroiliitis among patients with spondylarthropathy.
Methods: Fifteen patients with a history of inflammatory back pain without radiographic evidence of grade II or greater sacroiliitis (group 1), 25 patients with definite ankylosing spondylitis (group 2), and 12 patients with noninflammatory spinal pain (controls) (group 3) were examined. Dynamic MRI with fast imaging was performed after intravenous bolus injection of the contrast agent gadolinium-diethylenetriamine pentaacetic acid. The degree of enhancement was graded as representing acute sacroiliitis, latent sacroiliitis, or no sacroiliitis.
Results: Acute sacroiliitis was detected in 22 of 30 sacroiliac (SI) joints in group 1 patients and in 27 of 50 SI joints in group 2 patients; latent sacroiliitis was seen in 25 of 80 SI joints in patients from groups 1 and 2. No group 3 patient was found to have sacroiliitis.
Conclusion: Early sacroiliitis can be demonstrated by dynamic MRI in spondylarthropathy patients in whom abnormalities are not revealed by conventional radiography.