Atlantoaxial joints: patterns of gadolinium enhancement with MR imaging in normal subjects.
OBJECTIVE
To evaluate normal patterns of enhancement of signal intensity in and about the atlantoaxial joints following intravenous administration of a gadolinium-containing contrast agent.


METHODS
Fat-suppressed axial T1 weighted SE images were obtained in 12 patients without evidence of inflammmatory arthritis before and immediately after intravenous administration of a gadolinium-containing contrast agent. Patterns of enhancement of signal intensity in and about the atlantoaxial joints were evaluated qualitatively.


RESULTS
Four different MR imaging patterns were observed: no enhancement of signal intensity, enhancement in the form of a single punctate region, enhancement in a confluent pattern, and bandlike enhancement.


CONCLUSIONS
Enhancement occurs around the odontoid process in patients without evidence of rheumatoid arthritis (RA). The dividing line between early synovitis and normal enhancement seems broader than expected. The reasons remain unclear and warant further studies.
Department of Radiology, University of Vienna, Austria.
T
T
Rand
J
J
Healy
A
A
Brossmann
K
K
Muhle
P
P
Clopton
D
D
Resnick
D000328:Adult; D001268:Atlanto-Axial Joint / Q000033:anatomy & histology*; D003287:Contrast Media / Q000008:administration & dosage*; D005260:Female; D019786:Gadolinium DTPA / Q000008:administration & dosage*; D006801:Humans; D007275:Injections, Intravenous; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged
D003287:Contrast Media; C064925:gadodiamide; D019786:Gadolinium DTPA