ABSTRACT
The aim of this study was to compare the diagnostic capabilities of extremity MRI (E-MRI) with high-field MRI in arthritic small joints, and to evaluate the patients' acceptance and perceptions of the two MR systems. One hundred three patients (group 1 = 28 patients with RA < 3 years, group 2 = 25 patients with reactive and psoriatic arthritis and mixed connective tissue disease, group 3 = 25 patients with rheumatoid arthritis (RA) more than 3 years and group 4 = 25 patients with arthralgia) underwent dedicated E-MRI and high-field MRI of the wrist and finger joints. Coronal short tau inversion recovery and transversal 3D T1-weighted images before and after gadodiamide (Gd) were performed in both cases to outline the volume of the synovial membrane (Vsm) and to evaluate joints with enhancement, effusion, bone edema, and erosions. Investigators blinded to the clinical findings evaluated the images. Patients' compliance and acceptance of E-MRI and high-field MRI were evaluated. The median Vsm obtained on E-MRI did not differ significantly from that obtained on high-field MRI. Vsm = 1 ml (E-MRI) and 1.1 ml (high-field MRI) before Gd and Vsm = 0.1 ml (E-MRI) and 0 ml (high-field MRI) after Gd (Wilcoxon test, p > 0.05). The difference in agreement was 8% for joint enhancement, 2% for joint effusion, 3% for bone edema, and 4% for bone erosions. Of the patients, 64% preferred E-MRI due to more comfortable positioning and less claustrophobia and noise. Extremity MRI of the small arthritic joints is comparable to high-field MRI and more readily accepted than high-field MRI by this patient group.
Subject(s)
Arthritis, Psoriatic/diagnosis , Arthritis, Reactive/diagnosis , Arthritis, Rheumatoid/diagnosis , Image Enhancement , Image Processing, Computer-Assisted , Imaging, Three-Dimensional , Magnetic Resonance Imaging , Adult , Aged , Female , Humans , Joints/pathology , Male , Middle Aged , Reference Values , Sensitivity and Specificity , Synovial Membrane/pathologyABSTRACT
We evaluated the value of dedicated extremity magnetic resonance imaging (E-MRI) in patients with clinical suspicion of a scaphoid fracture and normal initial radiographs. 52 patients underwent E-MRI within a mean of 4 (2-10) days after trauma. Follow-up radiographs were performed at average 11 (8-14) weeks after trauma, and these images were used as the "gold standard". A T1-weighted turbo gradient echo 3D and a tau short inversion recovery STIR were performed, both in coronal planes. The imaging time was less than 10 min. The images were evaluated independently by two radiologists. E-MRI detected occult fractures of the scaphoid in 9 patients, and of the distal radius in a further 6 patients. All these fractures were confirmed at follow-up radiographs. Furthermore, E-MRI revealed a fracture of the capitate bone in 1 patient, and of the triquetrum in 2 patients, and in 8 patients, bone bruise in 1 or more of the carpal bones. However, these fractures and bone lesions could not be confirmed by the follow-up radiographs. The agreement between the two examiners was high (kappa = 0.8) for E-MRI detection of fractures. E-MRI seems to be better than radiographs in the early diagnosis of occult fractures of the scaphoid bone and the wrist.