[Diagnosis of initial changes in the hand of patients with rheumatoid arthritis--comparison between low-field magnetic resonance imaging, 3-phase bone scintigraphy and conventional x-ray].
Besides conventional X-rays, in the diagnostic work up of initial changes in patients suffering from rheumatoid arthritis (RA), 3-phase bone scintigraphy (3P-Sz) is as well established as magnetic resonance imaging (MRI). The aim of this study was to compare the diagnostic value of the newly developed low field MRI with the proven methods X-rays and 3P-Sz.


METHODS
65 patients (47f, 18m; 20-86 yrs) were studied on a one day protocol with 3P-Sz (550 MBq Tc-99m DPD), MRI and X-rays of the hands. Images were visually analysed by two blinded nuclear medicine physicians and radiologists and classified as a) RA-typical, b) inflammatory, non-RA-typical and c) non inflammatory changes. All methods were compared to 3P-Sz as golden standard.


RESULTS
In comparison to 3P-Sz, low field MRI presents with almost equal sensitivity and specificity in rheumatoid-typical and inflammatory changes. Conventional X-rays revealed in arthritis-typical changes as well as in inflammatory changes a significantly lower sensitivity and also a lower negative predictive value while specificity equals the one of MRI. Quantitative analysis of 3P-Sz using ROI-technique unveiled significantly higher values in patients with rheumatoid arthritis than in those with no inflammatory changes.


CONCLUSIONS
MRI represents an equally sensitive method in the initial diagnosis of rheumatoid-typical and inflammatory changes in the region of the hands as compared to the 3P-Sz. Besides the basic diagnosis with conventional X-rays, 3P-Sz is still the recommended method of choice to evaluate the whole body when RA is suspected. Additionally, quantitative analysis of the 3P-Sz using the ROI technique in the region of the hands reveals statistically significant results and should therefore be taken into account in the assessment of inflammatory changes.
Höpfner
S
S
Klinik und Poliklinik für Nuklearmedizin, Ludwig-Maximilians-Universität Innenstadt, München, Deutschland. stefan.hoepfner@radin.med.uni-muenchen.de
Treitl
M
M
Krolak
C
C
Becker-Gaab
C
C
Dresel
S
S
Weiss
M
M
Schattenkirchner
M
M
Hahn
K
K
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001172:Arthritis, Rheumatoid / Q000175:diagnosis* / Q000000981:diagnostic imaging; D001842:Bone and Bones / Q000000981:diagnostic imaging*; D005260:Female; D006225:Hand; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011859:Radiography; D011877:Radionuclide Imaging; D015203:Reproducibility of Results