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Objective: To evaluate the usefulness of dynamic gadolinium-enhanced magnetic resonance imaging (MRI) for assessing the viability of the proximal pole of the scaphoid in patients with acute scaphoid fractures., Methods: Eighteen consecutive patients with acute scaphoid fracture who underwent dynamic gadolinium-enhanced MRI 7 days or less before surgery were prospectively included between August 2011 and December 2012. All patients underwent MR imaging with unenhanced images, enhanced images, and dynamic enhanced images. A radiologist first classified the MRI results as necrotic or viable based on T1- and T2-weighted images only, followed by a second blinded interpretation, this time including analysis of pre- and post-gadolinium administration images and a third blinded interpretation based on the time-intensity curve of the dynamic enhanced study. The standard of reference was the histologic assessment of a cylindrical specimen of the proximal pole obtained during surgery in all patients. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for unenhanced, enhanced, and dynamic gadolinium-enhanced MRI studies., Results: The sensitivity, specificity, PPV, and NPV were 67, 67, 50, and 80 % for unenhanced images, 83, 100, 100, and 92 for enhanced images, and 83, 92, 83, and 92 for dynamic contrast-enhanced images., Conclusions: Our data are consistent with previously reported data supporting contrast-enhanced MRI for assessment of viability, and showing that dynamic imaging with time-intensity curve analysis does not provide additional predictive value over standard delayed enhanced imaging for acute scaphoid fracture.

Objectives: To correlate magnetic resonance imaging (MRI) aspects of the femoral head with histological findings in advanced hip osteoarthritis (OA), with special emphasis on bone marrow edema (BME)., Methods: MRI was performed in patients with advanced hip OA scheduled for hip arthroplasty. Coronal T1-, fat-suppressed T2-, T1 with gadolinium intravenous injection sequences were obtained on a 1.5 T MR-scanner within 1 month before surgery. Coronal MR images corresponding to the ligamentum teres plane were analyzed by two independent readers blinded to histological data. Normal bone marrow, subchondral cyst, subchondral fracture, edema-like, necrosis-like, and necrosis MR patterns were reported on a synthesis scheme. After surgery, the femoral heads specimens were cut through the ligamentum teres plane and histologically analyzed for correlations., Results: Twenty-three femoral heads were analyzed (female 56.5%, mean age 64.5 years). Edema-like MR pattern was correlated with histological (H) edema (Kappa (K): 0.77). Necrosis-like MR pattern was correlated with H fibrosis (K: 0.49) and with H necrosis (K: 0.24). Cyst MR pattern was correlated with H bone cysts (K: 0.58). Necrosis MR pattern corresponded to a mixture of histological lesions. Sensitivity and specificity of MRI varied from 26% to 80% and from 86% to 95% respectively., Conclusion: In advanced hip OA, the so-called "BME" MR lesion corresponds to a combination of edema, fibrosis, and necrosis at histopathology. When the classical "BME" is more specifically separated into edema-like and necrosis-like MR patterns, MR Imaging and histological findings show substantial agreement, with edema-like MR pattern mainly corresponding to histological edema., (Copyright © 2010 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.)

A 37-year-old man presented with a 2-year history of left hip pain. Pretherapeutic imaging demonstrated a 4 cm osteoblastoma located in the intertrochanteric region of the proximal femur, surrounded by extensive bone marrow edema. After multidisciplinary meeting, percutaneous cryoablation was decided and performed under computed tomography guidance using three cryoprobes to match the exact size and shape of the tumor, resulting in complete resolution of symptoms. Magnetic resonance imaging follow-up demonstrated resolution of the bone marrow edema pattern and ingrowth of fat at the periphery of the ablation zone consistent with long-term healing of the tumor. [ABSTRACT FROM AUTHOR]

Background: Preoperative diffusion-weighted MRI (DW-MRI) has been described as an efficient method to differentiate good and poor responders to chemotherapy in osteosarcoma patients. A DW-MRI performed earlier during treatment could be helpful in monitoring chemotherapy. Objective: To assess the accuracy of DW-MRI in evaluating response to chemotherapy in the treatment of osteosarcoma, more specifically at mid-course of treatment. Materials and methods: This study was carried out on a prospective series of adolescents treated for long-bone osteosarcoma. MR examinations were performed at diagnosis (MRI-1), at mid-course of chemotherapy (MRI-2), and immediately before surgery (MRI-3). A DW sequence was performed using diffusion gradients of b0 and b900. The apparent diffusion coefficients (ADC1, ADC2, ADC3, respectively), their differentials (ADC2 − ADC1 and ADC3 − ADC1), and their variation (ADC2 − ADC1/ADC1 and ADC3 − ADC1/ADC1) were calculated for each of these three time points. Results: Fifteen patients were included. Patients with no increase in ADC showed a poor response to chemotherapy on their histology results. At mid-course, the three calculated values were significantly different between good and poor responders. ADC2 − ADC1 enabled us to detect, with 100% specificity, four out of seven of the poor responders. There was no significant difference in the values at MRI-3 between the two groups. Conclusion: DW-MRI performed both at baseline and mid-course of neoadjuvant chemotherapy is an efficient method to predict further histological response of osteosarcoma. This method could be used as an early prognostic factor to monitor preoperative chemotherapy. [ABSTRACT FROM AUTHOR]