Acta radiologica
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Background Few studies have focused on diffusion tensor imaging (DTI) parameters of the conus medullaris after chronic compression in the cervical spinal cord. Purpose To discuss the correlation of DTI parameters between the chronically compressed cervical spinal cord and the conus medullaris in a rat model at different time points. Material and Methods Fifty female Sprague-Dawley rats were randomized into five groups: control group (group A), sham group (group B), and test groups C, D, and E (1, 2, and 3 weeks after compression, respectively). ⋯ There were no linear correlations of FA values between the cervical spinal cord and the conus medullaris in all test groups. Conclusion After compression of the cervical spinal cord, ADC values of the cervical spinal cord and conus medullaris in test group were significantly increased, while FA values were significantly decreased. The ADC value of the cervical spinal cord was linearly correlated with that of the conus medullaris at 2 weeks after compression.
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Background Using imaging techniques to diagnose malignant and inflammatory lesions in the lung can be challenging. Purpose To compare intravoxel incoherent motion (IVIM) and apparent diffusion coefficient (ADC) magnetic resonance imaging (MRI) analysis in their ability to discriminate lung cancer from focal inflammatory lung lesions. Material and Methods Thirty-eight patients with lung masses were included: 30 lung cancers and eight inflammatory lesions. ⋯ By IVIM, f was found to be significantly higher in inflammatory lesions than lung cancer ([46.10 ± 12.92] % vs. [29.29 ± 10.89] %; P = 0.005). There was no difference in D and D* between lung cancer and inflammatory lesions ( P = 0.747 and 0.124, respectively). f showed comparable diagnostic performance with ADC in differentiating lung cancer from inflammatory lung lesions, with areas under the curve of 0.833 and 0.826, sensitivity 80.0% and 73.3%, and specificity 75.0% and 87.5%, respectively. Conclusion The IVIM parameter f value provides comparable diagnostic performance with ADC and could be used as a surrogate marker for differentiating lung cancer from inflammatory lesions.
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Background There has been no comparison study to assess the diagnostic efficacy of additional anterior cruciate ligament (ACL) views in three-dimensional (3D) volume isotropic turbo spin-echo acquisition (VISTA) and two-dimensional (2D) fast spin-echo (FSE) T2-weighted (T2W) images for the diagnosis of ACL tear. Purpose To compare the diagnostic performances of additional ACL views on VISTA with those on the 2D FSE T2W images. Material and Methods This retrospective study included 78 patients who were suspected to have ACL injury and underwent both 2D TSE T2W magnetic resonance imaging (MRI) and 3D VISTA MRI of the knee between November 2012 and March 2013. ⋯ When considering both views of the oblique sagittal and coronal images, the inter-observer agreement between readers nearly concurred. There were no statistically significant differences in the sensitivity, specificity, and accuracy between 2D FSE images and VISTA images. Conclusion The performance of the additional ACL view on 3D VISTA MRI is comparable to that of 2D FSE T2W MRI in the diagnosis of ACL tear though the image quality of the 3D VISTA MRI is not equal to that of 2D FSE MRI.
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Review Multicenter Study
Effects of gadolinium-based contrast agent concentrations (0.5 M or 1.0 M) on the diagnostic performance of magnetic resonance imaging examinations: systematic review of the literature.
Background To date there is no agreement as to what is the optimal concentration for gadolinium-based contrast agents (GBCAs). Purpose To assess whether diagnostic performance differences exist between 0.5 M and 1.0 M GBCAs used for magnetic resonance imaging (MRI). Material and Methods A PubMed literature search identified 21 clinical studies published between 2005 and 2013 which evaluated the diagnostic efficacy of both types of GBCAs. ⋯ Methodological biases were identified in several studies impairing the interpretation of comparisons. Conclusion Imaging differences between 0.5 M and 1.0 M GBCAs were essentially observed under non-equimolar delivery rates. However, they did not result into greater diagnostic efficacy when performed under equimolar conditions.
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Background Cervical node metastasis is one of the most significant prognostic factors in patients with oropharyngeal squamous cell carcinoma (SCC). There is little information regarding the comparison of histopathologic analysis following neck dissection with imaging results in oropharyngeal SCC. Purpose To investigate the clinical utility of PET-CT compared with computed tomography (CT) or magnetic resonance imaging (MRI) for detecting nodal metastasis in oropharyngeal SCC patients with palpably negative neck and to investigate whether pretreatment imaging modalities support the rationale for elective neck treatment. ⋯ On a level-by-level analysis, the sensitivity of PET-CT, CT/MRI, and a combination of PET-CT and CT/MRI was 54.6%, 54.6%, and 60.6%, respectively, at all neck levels. The area under the ROC showed that the diagnostic performance of the combined interpretation was not significantly different from that of CT/MRI alone (0.780 vs. 0.750, respectively; P = 0.158) and PET-CT alone (0.780 vs. 0.765, respectively; P = 0.501). Conclusion Addition of PET-CT to CT/MRI did not provide better diagnostic accuracy for detecting nodal metastasis in preoperative evaluation of oropharyngeal SCC patients with palpably negative neck, suggesting that current imaging studies might not replace elective neck dissection.