Diagnostic accuracy was evaluated by using logistic generalized linear mixed-effect models and receiver operating characteristic (ROC) analysis. Correlation with Gleason score (GS) was evaluated with the Spearman rank correlation test. A paired t test was used to determine significant differences between MR parameters in malignant and nonmalignant tissue. From T2 distributions, maps of seven MR parameters, Ncomp, T2short, T2long, geometric mean T2 (gmT2), luminal water fraction (LWF), Ashort, and Along, were generated and compared with digitized images of hematoxylin-eosin-stained whole-mount histologic slices. T2 distributions were generated with a regularized non-negative least squares algorithm from multiecho spin-echo MR imaging data. Patients underwent 3.0-T MR imaging shortly before radical prostatectomy. Materials and Methods Eighteen patients with biopsy-proven PCa provided informed consent to be included in this institutional human ethics board-approved prospective study between January 2015 and January 2016. Purpose To assess the feasibility of luminal water imaging, a quantitative T2-based magnetic resonance (MR) imaging technique, for the detection and grading of prostate cancer (PCa). The biexponential model provided good signal prediction while predictions from the monoexponential models are dependent on the range of TE used for T2 determination. Prostate imaging with bSSFP benefited from high flip angles. The predicted contrast peaked at alpha between 50 degrees and 90 degrees. A monoexponential model restricted to the echoes TE = 50-125 ms performed similar to the biexponential model. The biexponential model was a better predictor of the measured signal than the monoexponential model. Mean R(2) for the biexponential model was almost constant for alpha in the range 50-110 degrees. The measured contrast to signal ratio increased continuously with alpha. Measured and predicted signals were compared by simple linear regression. One biexponential and two monoexponential models were applied. Predictions of signal and contrast were obtained from synthetic bSSFP images calculated from relaxation parameters obtained from a multi-spin-echo acquisition. In each of seven healthy volunteers, six 3D bSSFP acquisitions were performed with flip angles (alpha) equally spaced between 10 degrees and 110 degrees.
#Ivestigate the signal state of decay free
Wiki guardians are encouraged to read the administrators guide.To investigate the contrast of three-dimensional balanced steady state free precession (3D bSSFP) in the two component T2 model and to apply the results to optimize 3D bSSFP for prostate imaging at 1.5 Tesla. In every other way, wiki guardians are the same as administrators. Should that guardian become active again, their rights can be restored. There is no fixed period of inactivity after which wiki guardians are demoted, demotion is at wiki managers' discretion. If a wiki guardian is inactive on a wiki, the wiki manager assigned to that wiki may decide to remove their permissions. They are also expected to be active editors, adding game content, and working with the community in establishing the wiki's "style". They are in general expected to take more of a leadership role while establishing the wiki than an administrator on a more mature wiki. While in general, wiki administrators are no more than registered wiki users, who have been trusted with janitorial responsibilities, wiki guardians are also expected to be proactive in recruiting editors from within the game community, being active on forums, and/or social media. The role comes with the same default permission set as the normal administrator status but is in general granted at the very early stages of a wiki's existence, or because of a lack of an existing editorial community. A user with this role can be identified by having a special label on the profile page near the username. A wiki guardian is a special user who has claimed a wiki that had no previous admin, or the previous admin is no longer with the wiki.
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