A cadaveric simulation-teaching model for radiology residents.

Place: EnglandInternational audienc

Validation and Optimization of Proximal Femurs Microstructure Analysis Using High Field and Ultra-High Field MRI

International audienceTrabecular bone could be assessed non-invasively using MRI. However, MRI does not yet provide resolutions lower than trabecular thickness and a comparative analysis between different MRI sequences at different field strengths and X-ray microtomography (μCT) is still missing. In this study, we compared bone microstructure parameters and bone mineral density (BMD) computed using various MRI approaches, i.e., turbo spin echo (TSE) and gradient recalled echo (GRE) images used at different magnetic fields, i.e., 7T and 3T. The corresponding parameters computed from μCT images and BMD derived from dual-energy X-ray absorptiometry (DXA) were used as the ground truth. The correlation between morphological parameters, BMD and fracture load assessed by mechanical compression tests was evaluated. Histomorphometric parameters showed a good agreement between 7T TSE and μCT, with 8% error for trabecular thickness with no significative statistical difference and a good intraclass correlation coefficient (ICC > 0.5) for all the extrapolated parameters. No correlation was found between DXA-BMD and all morphological parameters, except for trabecular interconnectivity (R2 > 0.69). Good correlation (p-value 0.79). These results suggest that MRI could be of interest for bone microstructure assessment. Moreover, the combination of morphological parameters and BMD could provide a more comprehensive view of bone quality

Assessment of Bone Microarchitecture in Fresh Cadaveric Human Femurs: What Could Be the Clinical Relevance of Ultra-High Field MRI

International audienceMRI could be applied for bone microarchitecture assessment; however, this technique is still suffering from low resolution compared to the trabecular dimension. A clear comparative analysis between MRI and X-ray microcomputed tomography (μCT) regarding microarchitecture metrics is still lacking. In this study, we performed a comparative analysis between μCT and 7T MRI with the aim of assessing the image resolution effect on the accuracy of microarchitecture metrics. We also addressed the issue of air bubble artifacts in cadaveric bones. Three fresh cadaveric femur heads were scanned using 7T MRI and μCT at high resolution (0.051 mm). Samples were submitted to a vacuum procedure combined with vibration to reduce the volume of air bubbles. Trabecular interconnectivity, a new metric, and conventional histomorphometric parameters were quantified using MR images and compared to those derived from μCT at full resolution and downsized resolutions (0.102 and 0.153 mm). Correlations between bone morphology and mineral density (BMD) were evaluated. Air bubbles were reduced by 99.8% in 30 min, leaving partial volume effects as the only source of bias. Morphological parameters quantified with 7T MRI were not statistically different (p > 0.01) to those computed from μCT images, with error up to 8% for both bone volume fraction and trabecular spacing. No linear correlation was found between BMD and all morphological parameters except trabecular interconnectivity (R 2 = 0.69 for 7T MRI-BMD). These results strongly suggest that 7T MRI could be of interest for in vivo bone microarchitecture assessment, providing additional information about bone health and quality

Focal myositis: Sonographic findings

International audienceno abstrac

Correlation between the retroversion of the humeral head and the orientation of the intertubercular sulcus: a CT scan anatomical study

International audienceThe purpose was to study the anatomy of the humeral head, more specifically the retroversion of the humeral head and the orientation of the intertubercular sulcus, using CT scan, and to make correlations between those two entities of the proximal humerus. Sixty dry adult humeri from an osteological collection underwent CT scan from the proximal to the distal extremity. The measurements obtained by CT-reformation were recorded by two independent radiologists. We determined the humeral head axis, the transepicondylar axis, the retroversion of the humeral head, and the orientation of the intertubercular sulcus (ITS). Statistical analysis using SPSS determined the Pearson correlation coefficient. The CT scan measurements were similar to those in the literature, and thus allowed us to validate CT scan assessment. Statistical analysis showed a significant reverse correlation [the coefficient of correlation was -0.37 (p = 0.004)] between the retroversion of the humeral head and the orientation of the intertubercular sulcus: the more the retroversion of the humeral head increases, the more the angle of the orientation of the ITS decreases. To the best of our knowledge, this reverse correlation between the retroversion of the humeral head and the orientation of the intertubercular sulcus has never been described. This new anatomical data might be helpful for orthopedic surgery

Control of the glottal configuration in ex vivo human models: quantitative anatomy for clinical and experimental practices

Introduction The objective of this paper was to identify the determining factors of the glottal prephonatory configuration from the point of view of the resulting muscular actions (i.e., arytenoids adduction, membranous vocal fold adduction, and tension). Materials and methods 21 human non-embalmed excised larynges (12 females and 9 males) were studied. Experiment A (11 larynges) studied four conditions of adduction of the vocal folds and arytenoids. Experiment B (10 larynges) studied the effect of cricothyroid approximation on the vocal fold length and the cricothyroid angle. Results Experiment A: The mean glottal area significantly decreased from 41.2 mm2 mean with no adduction, to 10.2 mm2 mean with arytenoid adduction, to 9.2 mm2 with membranous vocal fold adduction, and down to 1.1 mm2 with the combination of arytenoid and membranous adduction. The effect of the task was statistically significant. Experiment B: The length of vocal folds increased from 13.61 mm median to 14.48 mm median, and the cricothyroid angle decreased of 10.05 median along with cricothyroid approximation. Discussion The results of experiment A emphasize the sub-division of adductor intrinsic muscles in arytenoids adductors (i.e., LCA and IA), and membranous vocal fold adductor (i.e., TA). The results of experiment B quantify the effect of cricothyroid approximation on the vocal folds length. The implications of these results can be useful in both clinical practice and experimental studies

Diagnostic Performance of Flat-Panel CT Arthrography for Cartilage Defect Detection in the Ankle Joint: Comparison With MDCT Arthrography With Gross Anatomy as the Reference Standard

International audienceOBJECTIVE. The purpose of this study is to compare the diagnostic performance and radiation exposure of flat-panel CT arthrography for cartilage defect detection in the ankle joint to standard MDCT arthrography, using gross anatomy and thermoluminescent dosimetry as reference standards. MATERIALS AND METHODS. Ten cadaveric ankle specimens were obtained from individuals who had willed their bodies to science. Five milliliters of a mixture of diluted ioxaglate and saline were injected. Specimens were examined consecutively with the use of flat-panel CT and MDCT. Radiation doses of flat-panel CT and MDCT were recorded using thermoluminescent dosimeters. Flat-panel CT and MDCT arthrography examinations were blinded and randomly evaluated by two musculoskeletal radiologists in consensus. In each ankle specimen, eight cartilage areas were assessed separately: medial talar surface, medial talar trochlea, lateral talar trochlea, lateral talar surface, tibial malleolus, medial tibial plafond, lateral tibial plafond, and fibular malleolus. Findings at flat-panel CT and MDCT arthrography were compared with macroscopic assessments in 80 cartilage areas. RESULTS. For the detection of cartilage lesions, flat-panel CT showed a sensitivity of 80%, specificity of 98%, and accuracy of 94%, and MDCT arthrography showed a sensitivity of 55%, specificity of 98%, and accuracy of 88%. Flat-panel CT and MDCT arthrography showed almost perfect (kappa = 0.83) and substantial (kappa = 0.65) agreement, respectively, with anatomic examination. Radiation dose was significantly lower for flat-panel CT (mean, 2.1 mGy; range, 1.1-3.0 mGy) than for MDCT (mean, 47.2 mGy; range, 39.3-53.8 mGy) (p < 0.01). CONCLUSION. Flat-panel CT arthrography is accurate for detecting cartilage defects in the ankle joint and is an alternative to MDCT arthrography that may have better diagnostic performance and may permit the use of a lower radiation dose

Intradiscal oxygen-ozone therapy for the treatment of symptomatic lumbar disc herniation: A preliminary study.

Place: FranceInternational audiencePURPOSE: To assess safety and effectiveness of computed tomography (CT)-guided intradiscal oxygen-ozone therapy (O(2)-O(3) therapy) for the treatment of symptomatic lumbar disc herniation and radiological changes. MATERIALS AND METHODS: This study was conducted in twenty patients presenting lumbar disc herniation with resistant lumbar or lumbar radicular pain They underwent intradiscal oxygen-ozone therapy under CT guidance. They were treated at one- or two-disc levels, representing a total of 24 discs treated. MR imaging examinations were obtained before treatment and 2 months post-procedure to analyse treatment-related disc modifications including modification of the surfaces of the disc and of the herniated disc, and the variations in disc height according to the disc height index. Clinical outcomes were assessed using the visual analogue scale (VAS) to evaluate the severity of pain before the procedure, at primary (2 months) and at secondary (12 months) follow-ups. RESULTS: All the procedures were technically successful. The median VAS scores were 7.95 before the procedure, 3.9 at 2 months and 2.95 at 12 months. MRI analysis showed a significant decrease in herniation size at 2 months (-20%, p = 0.008). No immediate or late complications were observed. Only three patients (13.6%) underwent lumbar spine microdiscectomy in the year following ozone therapy. The treatment appeared to be more effective in cases of nerve root symptomatology. CONCLUSION: This study suggests that intradiscal O(2)-O(3) therapy is safe and effective for the treatment of lumbar disc herniation associated with resistant lumbar or lumbar radicular pain