Comparison of diagnostic quality and accuracy in color-coded versus gray-scale DCE-MR imaging display
ABSTRACT PurposeThe purpose of this study was to evaluate the diagnostic value and tumor-vascular display properties (microcirculation) of
two different functional MRI post-processing and display (color and gray-scale display) techniques used in oncology.
Materials and methodsThe study protocol was approved by the IRB and written informed consent was obtained from all patients. 38 dynamic contrast
enhanced magnetic resonance imaging (DCE-MRI) data sets of patients with malignant pleural-mesothelioma were acquired and
post-processed. DCE-MRI was performed at 1.5tesla with a T1-weighted 2D gradient-echo-sequence (TR 7.0ms, TE 3.9ms, 15
axial slices, 22 sequential repetitions), prior and during chemotherapy. Subtracting first image of contrast-enhanced-dynamic
series from the last, produced gray-scale images. Color images were produced using a pharmacokinetic two-compartment model.
Eight raters, blinded to diagnosis, by visual assessment of post-processed images evaluated both diagnostic quality of the
images and vasculature of the tumor using a rating scale ranging from −5 to +5. The scores for vasculature were assessed by
correlating with the maximum amplitude of the total-tumor-ROI for accuracy.
ResultsColor coded images were rated as significantly higher in diagnostic quality and tumor vascular score than gray-scale images
(p < 0.001, 0.005). ROI signal amplitude analysis and vascular ratings on color coded images were better correlated compared
to gray-scale images rating (p < 0.05).
ConclusionColor coded images were shown to have higher diagnostic quality and accuracy with respect to tumor vasculature in DCE-MRI,
therefore their implementation in clinical assessment and follow-up should be considered for wider application.
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ABSTRACT: To investigate the use of diffusion-weighted (DW) imaging for differentiating benign lesions from malignant pleural disease (MPD) and to retrospectively assess dynamic contrast material-enhanced (DCE) magnetic resonance (MR) imaging acquisitions to find out whether combining these measurements with DW imaging could improve the diagnostic value of DW imaging. This study was approved by the local ethics committee, and all patients provided written informed consent. Thirty-one consecutive patients with pleural abnormalities suspicious for MPD underwent whole-body positron emission tomography (PET)/computed tomography (CT) and thorax MR examinations. Diagnostic thoracoscopy with histopathologic analysis of pleural biopsies served as the reference standard. First-line evaluation of each suspicious lesion was performed by using the apparent diffusion coefficient (ADC) calculated from the DW image, and the optimal cutoff value was found by using receiver operating characteristic curve analysis. Afterward, DCE MR imaging data were used to improve the diagnosis in the range of ADCs where DW imaging results were equivocal. Sensitivity, specificity, and accuracy of PET/CT for diagnosis of MPD were 100%, 35.3%, and 64.5%. The optimal ADC threshold to differentiate benign lesions from MPD with DW MR imaging was 1.52 × 10(-3) mm(2)/sec, with sensitivity, specificity, and accuracy of 71.4%, 100%, and 87.1%, respectively. This result could be improved to 92.8%, 94.1%, and 93.5%, respectively, when DCE MR imaging data were included in those cases where ADC was between 1.52 and 2.00 × 10(-3) mm(2)/sec. A total of 20 patients had disease diagnosed correctly, nine had disease diagnosed incorrectly, and two cases were undetermined with PET/CT. DW imaging helped stage disease correctly in 27 patients and incorrectly in four. The undetermined cases at PET/CT were correctly diagnosed at MR imaging. DW imaging is a promising tool for differentiating MPD from benign lesions, with high accuracy, and supplementation with DCE MR imaging seems to further improve sensitivity.Radiology 04/2012; 263(3):884-92. DOI:10.1148/radiol.12110872 · 6.21 Impact Factor
Medical Hypotheses 03/2011; 76(5):764-5. DOI:10.1016/j.mehy.2011.02.011 · 1.15 Impact Factor
Medical Hypotheses 02/2011; 76(5):764. DOI:10.1016/j.mehy.2011.02.006 · 1.15 Impact Factor