Magnetic Resonance Imaging of Pseudotumors of the Craniovertebral Junction in Long-Term Hemodialysis Patients

Background/Aims: Pseudotumors of the craniovertebral junction (PTCVJ) are observed in long-term hemodialysis (HD) patients. There are neither criteria for diagnosis nor guidelines for screening. We attempted to determine magnetic resonance imaging (MRI) findings that could be used to detect PTCVJ, to determine the prevalence of PTCVJ, and to evaluate whether destructive spondyloarthropathy (DSA) might be a yardstick for selection of patients for MRI examination for PTCVJ. Methods: MRI were examined in 19 DSA patients (8 males, 11 females, age 61.4 ± 7.3 years, HD duration 17.0 ± 4.4 years) and in 20 sex-, age-, and HD-duration-matched non-DSA patients (9 males, 11 females, age 57.5 ± 6.6 years, HD duration 17.7 ± 4.9 years). We evaluated MRI characteristics of PTCVJ according those which occur due to rheumatoid arthritis. Results: PTCVJ were characterized as follows: disappearance of fat pads in the upper region (supradental PTCVJ), intensity change of the ‘predental triangle’ in the anterior region (predental PTCVJ), and thickening of cruciform ligaments (retrodental PTCVJ). The prevalence of PTCVJ among patients undergoing HD more than 10 years was high (26 out of 39; 66.7%). The prevalence of PTCVJ was not different between DSA and non-DSA groups. Conclusion: We verified that the above MRI findings might be helpful in the detection of PTCVJ. These findings were observed frequently and independently also in patients with DSA.