Page 68 - Imaging of Osteoarthritis and Rheumatoid Arthritis in Hand Joints

Chapter 4
Methods
Patients
We recruited 20 symptomatic patients who had been scheduled for trapeziectomy or hemitrapeziectomy to treat OA in the CMC1 joint. From April 2010 until October 2011 consecutive eligible patients at a University hospital and two teaching hospitals in the Netherlands were invited to participate in the study. The indication for surgery was based on severe pain and/or loss of function. Prior to surgery, patients underwent MRI and functional assessment of the thumb. Patients with previous surgery to the thumb base, or patients with contra-indications to MRI scanning were excluded. Patients were operated by their own treating hand surgeon. Additionally two healthy controls were included for comparison of MRI images only. This study was approved by the local ethics committees of the participating hospitals. All patients provided written informed consent prior to the investigation.
MRI acquisition
MR images were obtained using 3.0T scanners (GE HD and GE Discovery MR750, GE healthcare, Milwaukee, Wisconsin). Patients were placed in the prone position with the arm extended above the head, the hand placed in the center of the magnet, and the thumb fully extended on a custom-made platform to stabilize and immobilize the hand. A custom-made 4.0 mm loop coil was placed on the dorsal side of the CMC1 joint and taped to the hand. Sagittal 3D fast spoiled gradient (SPGR) sequences with fat saturation (FS) were obtained with a spatial resolution of 0.1 by 0.2 mm (echo time (TE) minimal; field of view (FOV) 3-4 cm; frequency 256-320; phase 128-224; slice thickness 0.7 mm; bandwidth 15.6 kHz; two signals acquired). Proton density weighted fast recovery fast spin echo (FRFSE) sequences were acquired in the coronal and sagittal plane (repetition time (TR) 2400; TE 30; echo train length (ETL) 6; FOV 3-4 cm; frequency 256-320; phase 128-160; slice thickness 1.0 mm; bandwidth 15.6 kHz; three signals acquired). T2 weighted FRFSE sequences with fat saturation were obtained in coronal direction (TR 3000; TE 68; ETL 6; FOV 4 cm; frequency 192; phase 128; slice thickness 2.0 mm; bandwidth 15.6 kHz; four signals acquired). The scanning acquisition time was 25 minutes.
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