A. Feydy

Diagnostic Imaging of Solitary Tumors of the Spine: What to Do and Say

Metastatic disease, myeloma, and lymphoma are the most common malignant spinal tumors. Hemangioma is the most common benign tumor of the spine. Other primary osseous lesions of the spine are more unusual but may exhibit characteristic imaging features that can help the radiologist develop a differential diagnosis. Radiologic evaluation of a patient who presents with osseous vertebral lesions often includes radiography, computed tomography (CT), and magnetic resonance (MR) imaging. Because of the complex anatomy of the vertebrae, CT is more useful than conventional radiography for evaluating lesion location and analyzing bone destruction and condensation. The diagnosis of spinal tumors is based on patient age, topographic features of the tumor, and lesion pattern as seen at CT and MR imaging. A systematic approach is useful for recognizing tumors of the spine with characteristic features such as bone island, osteoid osteoma, osteochondroma, chondrosarcoma, vertebral angioma, and aneurysmal bone cyst. In the remaining cases, the differential diagnosis may include other primary spinal tumors, vertebral metastases and major nontumoral lesions simulating a vertebral tumor, Paget disease, spondylitis, echinococcal infection, and aseptic osteitis. In many cases, vertebral biopsy is warranted to guide treatment.

The DESIR cohort: A 10-year follow-up of early inflammatory back pain in France: Study design and baseline characteristics of the 708 recruited patients

OBJECTIVES The French Society of Rheumatology has initiated a large national multicenter, longitudinal, prospective follow-up of patients presenting with early inflammatory back pain in order to set up a database to facilitate several investigations on diagnosis, prognosis, epidemiology, pathogenesis and medico-economics in the field of early inflammatory back pain and spondyloarthritis. METHODS Patients were recruited if they had inflammatory back pain of more than 3 months and less than 3 years. Patients will be followed every 6 months during the first 2 years then every year during at least 5years. Apart from information collected on a Case Report Form (demographics, disease activity, severity, co-morbidities, socio-economics, treatments, radiological and MRI evaluation of the spine and the pelvis according to the local investigators, and for some centers bone densitometry and ultrasonography of entheses), the digital X-rays and MRI of the spine and pelvis are stored using a specific software (Carestream) and the biological samples (DNA, RNA, sera, urines) are centralized at the Biological Resources Center (Bichat Hospital). RESULTS The recruitment period of the 708 patients (mean age: 34±9years, female 54%, HLA-B27 positive: 57%) in the 25 centers was 26 months (from December 2007 to April 2010). The modified New York criteria, Amor criteria, ESSG criteria and axial ASAS criteria were fulfilled by 26%, 77%, 76% and 67% of the patients at entry, respectively. A history or current symptoms suggestive of peripheral arthritis, acute anterior uveitis and inflammatory bowel disease were observed in 21%, 9% and 4% of the patients, respectively. The disease was active (BASDAI: 45±20) despite an NSAID intake in 66% of the patients. CONCLUSION This large cohort should facilitate the conduct of researches in different areas (clinical, medico-economics, translational) in order to improve our knowledge on the pathogenesis and natural history of axial spondyloarthritis.

Virtual Monochromatic Spectral Imaging with Fast Kilovoltage Switching: Reduction of Metal Artifacts at CT

With arthroplasty being increasingly used to relieve joint pain, imaging of patients with metal implants can represent a significant part of the clinical work load in the radiologists daily practice. Computed tomography (CT) plays an important role in the postoperative evaluation of patients who are suspected of having metal prosthesis-related problems such as aseptic loosening, bone resorption or osteolysis, infection, dislocation, metal hardware failure, or periprosthetic bone fracture. Despite advances in detector technology and computer software, artifacts from metal implants can seriously degrade the quality of CT images, sometimes to the point of making them diagnostically unusable. Several factors may help reduce the number and severity of artifacts at multidetector CT, including decreasing the detector collimation and pitch, increasing the kilovolt peak and tube charge, and using appropriate reconstruction algorithms and section thickness. More recently, dual-energy CT has been proposed as a means of reducing beam-hardening artifacts. The use of dual-energy CT scanners allows the synthesis of virtual monochromatic spectral (VMS) images. Monochromatic images depict how the imaged object would look if the x-ray source produced x-ray photons at only a single energy level. For this reason, VMS imaging is expected to provide improved image quality by reducing beam-hardening artifacts.

A randomised, multicentre, double-blind, placebo-controlled trial of etanercept in adults with refractory heel enthesitis in spondyloarthritis: the HEEL trial

Objective Inflammation at the entheses is a distinguishing feature of spondyloarthritis (SpA). Enthesitis at the heel is the most common location and is often chronic, refractory to standard treatment and may have socioeconomic consequences. The objective of this study was to investigate the efficacy of etanercept in refractory heel enthesitis related to SpA. Methods The present work was a 12-week, randomised, double-blind, placebo-controlled study compared etanercept with placebo in patients with SpA according to Amors criteria, and heel enthesitis proven by MRI. The primary efficacy end point was the normalised net incremental area under the curve (AUC) between randomisation and week 12 for the patients global assessment (PGA) of disease activity. Secondary end points included change from baseline in PGA, heel pain, the Western Ontario and McMaster Universities Osteoarthritis index (WOMAC) function subscale and improvement in enthesitis as measured by MRI. Results A total of 24 patients were randomised. Mean normalised net incremental AUC for PGA of disease activity over 12 weeks was significantly greater in the etanercept versus placebo group: −28.5 versus −11.1, respectively (p=0.029). Significant improvements were also reported in the etanercept versus placebo group for PGA, −37.6 versus −11.6 (p=0.007); heel pain, −36.7 versus −13.1 (p=0.022); and WOMAC function, −23.2 versus −7.8 (p=0.024). No significant changes were observed in the MRI findings between groups. No unexpected adverse events or changes in laboratory values or vital signs. Conclusions This trial is the first randomised placebo-controlled study of an anti-tumour necrosis factor (TNF) agent in refractory heel enthesitis in patients with SpA. It demonstrates that etanercept has a statistically significant and clinically relevant benefit in such patients. ClinicalTrials.gov identifier NCT00420303.

Sonographic Appearance of Trigger Fingers

Objective. The purpose of this study was to describe the sonographic appearance of the first annular (A1) pulley–flexor tendon complex in patients with trigger fingers. Methods. Thirty‐three trigger fingers in 33 patients were examined with a 7‐ to 15‐MHz probe. A control group consisted of 20 patients without trigger fingers. The study included systematic measurement of the thickness of the A1 pulley and a power Doppler assessment of the pulleys, tendons, and tendon sheaths. Results. Thickening and hypoechogenicity of the A1 pulley were found in all patients with trigger fingers. Measurements of A1 pulley thickness were significantly different (P < .0001) between the groups without trigger fingers (mean, 0.5 mm; range, 0.4–0.6 mm) and with trigger fingers (mean, 1.8 mm; range, 1.1–2.9 mm). Hypervascularization of the A1 pulley on power Doppler imaging was found in 91% of the trigger fingers but was never found in the healthy control group. Flexor tendinosis was found in 48% of the trigger fingers; tenosynovitis was found in 55%; and both were found in 39%. In the control group, tenosynovitis and tendinosis were not found. Conclusions. Thickening and hyper‐vascularization of the A1 pulley are the hallmarks of trigger fingers on sonography. Other frequently observed features include distal flexor tendinosis and tenosynovitis.

Longitudinal stress fractures of the tibia: comparative study of CT and MR imaging.

Abstract. The aim of this study was to compare the performance of CT and MRI in the diagnosis of longitudinal stress fracture of the tibia (LSFT). A retrospective study of imaging findings was performed in 15 patients with LSFT. The CT and MR images were compared for detection of fracture line, callus, bone marrow edema, and soft tissues changes. The CT and MRI techniques allowed the detection of the fracture line in 82 and 73 % of cases, respectively. The callus was always visualized with CT or MRI. The MRI technique had a markedly higher sensitivity than CT in the detection of bone marrow edema (73 vs 18 %) and soft tissue lesions (87 vs 9 %). This may cause a misleading aggressive appearance on MRI. Computed tomography remains the best imaging modality for diagnosis of LSFT. However, MRI findings should be known to obviate the performance of CT or bone biopsy.

Agreement Between Clinical Practice and Trained Central Reading in Reading of Sacroiliac Joints on Plain Pelvic Radiographs: Results From the DESIR Cohort

To investigate the degree of agreement between local rheumatologists/radiologists and central trained readers (external standard) on the presence/absence of sacroiliitis on radiographs of the sacroiliac (SI) joints.

Comparative study of MRI and power Doppler ultrasonography of the heel in patients with spondyloarthritis with and without heel pain and in controls

Introduction Imaging of heel enthesopathy in spondyloarthritis (SpA) could potentially be useful for diagnosis and monitoring. The aim of this study was to assess the diagnostic capacities of MRI and power Doppler ultrasonography (PDUS) of the heel to distinguish patients with SpA from controls and to distinguish between patients with SpA with and without enthesopathy. Methods A cross-sectional single-centre study was performed in 51 patients (102 heels) with definite SpA according to Amors criteria. Patients with degenerative non-inflammatory low back pain (n=24, 48 heels) were included as controls. Bilateral heel MRI and PDUS were performed by two senior musculoskeletal radiologists blinded to the clinical and biological data on the same day as the clinical evaluation. The data were analysed by patient and by heel. Results Neither MRI nor PDUS could discriminate between patients with SpA and controls; bone oedema on MRI was the only abnormality specific to SpA (94%), but with a poor sensitivity (22%). However, among patients with SpA, painful heels had more inflammatory abnormalities (81% by MRI, 58% by PDUS) than heels with no pain (56% at MRI, 17% at PDUS). Conclusion Heel MRI and PDUS frequently show inflammatory lesions in SpA, particularly in painful heels. However, they were also often abnormal in controls. These results suggest that heel MRI and PDUS cannot be used for the diagnosis of SpA. However, PDUS and MRI may be useful for the depiction and assessment of enthesis inflammatory lesions in patients with SpA with heel pain.

Cervical spine and crystal-associated diseases: imaging findings

The cervical spine may be specifically involved in crystal-associated arthropathies. In this article, we focus on the three common crystals and diseases: hydroxyapatite crystal deposition disease, calcium pyrophosphate dihydrate (CPPD) deposition disease, and monosodium urate crystals (gout). The cervical involvement in crystal-associated diseases may provoke a misleading clinical presentation with acute neck pain, fever, or neurological symptoms. Imaging allows an accurate diagnosis in typical cases with calcific deposits and destructive lesions of the discs and joints. Most of the cases are related to CPPD or hydroxyapatite crystal deposition; gout is much less common.

White Matter Organization in Cervical Spinal Cord Relates Differently to Age and Control of Grip Force in Healthy Subjects

Diffusion tensor imaging (DTI) can be used to elucidate relations between CNS structure and function. We hypothesized that the degree of spinal white matter organization relates to the accuracy of control of grip force. Healthy subjects of different age were studied using DTI and visuomotor tracking of precision grip force. The latter is a prime component of manual dexterity. A regional analysis of spinal white matter [fractional anisotropy (FA)] across multiple cervical levels (C2–C3, C4–C5, and C6–C7) and in different regions of interest (left and right lateral or medial spinal cord) was performed. FA was highest at the C2–C3 level, higher on the right than the left side, and higher in the lateral than in the medial spinal cord (p < 0.001). FA of whole cervical spinal cord (C2–C7) was lower in subjects with high tracking error (r = −0.56, p = 0.004) and decreased with age (r = −0.63, p = 0.001). A multiple regression analysis revealed an independent contribution of each predictor (semipartial correlations: age, r = −0.55, p < 0.001; tracking error, r = −0.49, p = 0.003). The closest relation between FA and tracking error was found at the C6–C7 level in the lateral spinal cord, in which the corticospinal tract innervates spinal circuitry controlling hand and digit muscles. FA of the medial spinal cord correlated consistently with age across all cervical levels, whereas FA of the lateral spinal cord did not. The results suggest (1) a functionally relevant specialization of lateral spinal cord white matter and (2) an increased sensitivity to age-related decline in medial spinal cord white matter in healthy subjects.