Arthritis & Rheumatism, Volume 63,
November 2011 Abstract Supplement
Abstracts of the American College of
Rheumatology/Association of Rheumatology Health Professionals
Annual Scientific Meeting
Chicago, Illinois November 4-9, 2011.
Comparison of High-Resolution Multi-Pinhole SPECT and MRI for Monitoring Early Arthritis Patients Under Methotrexat Therapy: First Results.
Buchbender1, Christian, Sewerin1, Philipp, Scherer1, Axel, Miese1, Falk, Sander1, Oliver, Mattes-Gyorgy1, Katalin, Wittsack1, Hans-Jörg
To compare Magnetic Resonance Imaging (MRI) and Multi-pinhole Single-Photon-Emission Computed Tomography (MPH-SPECT) for the detection of joint inflammation in early rheumatoid arthritis (ERA) after six months Methotrexate therapy.
The clinically dominant hand of five consecutive ERA patients (4 f, 1 m, disease duration < 6 months, therapy-naive for DMARD, mean-values: CRP 15 mg/l, DAS 28 4.9, CCP 115.6 U/l, Rheumatoid factor 628 U/l) and involvement of the metacarpophalangeal (MCP) joints was imaged with a MPH-SPECT system at baseline (T0) and six months (T1) after initiation of methotrexate (MTX) therapy (15 mg/weekly p.o. or s.c.). SPECT (Picker PRISM 2000 S camera (Philips Medical Systems), MPH pyramidal collimator reaching a spatial resolution < 1 mm)) imaging was performed with 550 megabequerel (MBq) of technetium-99m dicarboxy propane disphosphonate (Tc99m-DPD). SPECT FoV was 110 × 100 mm covering the MCP, proximal and distal interphalangeal joints. Ratios of Tc99m-DPD uptake in MPH-SPECT were calculated intra-individually for MCP joints in relation to a non-involved joint in each patient. MR imaging of the same hand was contemporaneously performed on a 3T system (Magnetom Trio; Siemens Healthcare, Germany) using a 4 channel flex coil (imaging protocol: coronal STIR, coronal T1-TSE, dynamic T1 contrast enhanced, contrastenhanced coronal T1-TSE, axial contrast-enhanced T1-FS SE. MRI was evaluated based on the RAMRIS subset scores for synovitis, bone marrow edema (BME), and erosions. MPH-SPECT and MRI data of the two time points were compared (T0 and T1). Mann-Whitney-U test was used to test for differences in Tc99m-DPD uptake between the two time points.
Clinically all patients respond to MTX (mean values (T1) DAS 28 1.4, CRP 2 mg/l). MPH-SPECT at T0 revealed increased bone metabolism in 12 out of 20 MCP joints. The mean Tc99m-DPD uptake ratio at baseline was 2.1 ± 1.2 (Range 1.2 5.7). All 12 joints showed synovitis on baseline MRI scans. BME and erosions were found in one MCP joint. 10/12 showed a decreased bone metabolism after six month compared to baseline SPECT. The mean Tc99m-DPD uptake ratio of the follow up SPECT was 1.5 ± 0.46 (Range 1.12.7). We found that bone metabolism on follow-up was significantly decreased compared to baseline (p= 0.013). Bone metabolism showed an average decrease of 35%. The follow-up MRI scans revealed improvement of synovitis in 10/12 MCP joints. Despite improvement, synovitis was still present in 6/12 joints. No change or progression of erosionsdetected on baseline MRIwas found at T1. No change of BME (1 MCP) was seen.
In comparison to MRI, MPH-SPECT more frequently reveals early inflammatory involvement of the bone (potentially prior to BME). In ERA, therapy monitoring using MRI was limited to soft tissue inflammation. Thus MPH-SPECT might represent an additional tool for monitoring initial bony alterations in inflammatory joints diseases, such as ERA. Further studies are needed to support this hypothesis.
To cite this abstract, please use the following information:
Buchbender, Christian, Sewerin, Philipp, Scherer, Axel, Miese, Falk, Sander, Oliver, Mattes-Gyorgy, Katalin, et al; Comparison of High-Resolution Multi-Pinhole SPECT and MRI for Monitoring Early Arthritis Patients Under Methotrexat Therapy: First Results. [abstract]. Arthritis Rheum 2011;63 Suppl 10 :945