Tomosynthesis of the wrist and hand in patients with rheumatoid arthritis: comparison with radiography and MRI.
OBJECTIVE
The purpose of this article is to compare tomosynthesis with radiography and MRI of the wrist and hand for evaluating bone erosion in patients with rheumatoid arthritis (RA).


METHODS
Twenty consecutive patients with an established diagnosis of RA and five control patients were included in this study. They underwent radiography, tomosynthesis, and MRI of the bilateral hand and wrist within a week. The mean total dose of radiography and tomosynthesis was 0.13 and 0.25 mGy, respectively. MRI evaluation was performed according to the Outcome Measures in Rheumatology Clinical Trials recommendations. Bone erosion on images from the three modalities was independently reviewed by two certificated radiologists with a 4-point scale (0, normal; 1, discrete erosion; 2, < 50% of the joint surface; and 3, ≥ 50% of the joint surface).


RESULTS
The detection rates of bone erosion for radiography, tomosynthesis, and MRI were 26.5%, 36.1%, and 36.7%, respectively. Significantly more bone erosions were revealed with tomosynthesis and MRI than with radiography (p < 0.01). When MRI was used as the reference standard, the sensitivity, specificity, and accuracy were 68.1%, 97.5%, and 86.7%, respectively, for radiography and 94.8%, 97.8%, and 96.7%, respectively, for tomosynthesis. Interobserver agreement (kappa value) for bone erosion was good to excellent on tomosynthesis and MRI for all joints (0.65-1.00 and 0.68-1.00, respectively), whereas it was slight to fair on radiography for some carpal bones and bases of metacarpal bones (0.22-0.56).


CONCLUSIONS
Tomosynthesis is superior to radiography and almost comparable to MRI for the detection of bone erosion in patients with RA.
1 Department of Radiology, University of Occupational and Environmental Health School of Medicine, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan.
Takatoshi
T
Aoki
Masami
M
Fujii
Yoshiko
Y
Yamashita
Hiroyuki
H
Takahashi
Hodaka
H
Oki
Yoshiko
Y
Hayashida
Kazuyoshi
K
Saito
Yoshiya
Y
Tanaka
Yukunori
Y
Korogi
D000328:Adult; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000175:diagnosis* / Q000000981:diagnostic imaging; D016022:Case-Control Studies; D005260:Female; D006225:Hand / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011859:Radiography; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014955:Wrist Joint / Q000473:pathology*