While overall diagnostic performance in local staging of patients with prostate cancer at intermediate to high risk was similar, use of a gallium 68 (68Ga)-labeled Glu-urea-Lys (Ahx)-HBED-CC ligand... Background Recent studies have reported the additive value of combined gallium 68 (68Ga)-labeled Glu-urea-Lys (Ahx)-HBED-CC ligand targeting the prostate-specific membrane antigen (PSMA) (hereafter...

For the detection of clinically significant prostate cancer, no difference was found in diagnostic performance with a dual-pulse sequence biparametric MR imaging protocol consisting of transverse T... Purpose To compare the diagnostic performance of a short dual–pulse sequence magnetic resonance (MR) imaging protocol versus a standard six–pulse sequence multiparametric MR imaging protocol for de...

To compare the accuracy of dynamic gadolinium-enhanced magnetic resonance (MR) imaging with that of standard MR imaging for assessing the viability of the proximal pole of the scaphoid in patients with nonunion. The study protocol was submitted to the institutional review board, and the need to obtain additional approval was waived for this retrospective study. Twenty-eight patients (mean age ± standard deviation, 24.3 years ± 6.4) with nonunion of a scaphoid fracture underwent dynamic gadolinium-enhanced MR imaging of the wrist 28 days ± 19 before surgery. Dynamic gadolinium-enhanced MR imaging consisted of acquisition of 40 consecutive coronal T1-weighted images over 1 minute. Two readers retrospectively evaluated MR images obtained with a standard protocol and rated the viability of the proximal scaphoid pole. The steepest upslope of gadolinium uptake was calculated in a region of interest placed in the proximal scaphoid pole by a third reader. Receiver operating characteristic curves were calculated, and the areas under the receiver operating characteristic curve (A(z) values) were compared. Diagnostic performance in determining scaphoid viability was calculated for readers 1 and 2. Histologic findings in 11 patients and surgical findings in all patients served as the standard of reference. The sensitivity, specificity, and accuracy of standard MR imaging in the detection of scaphoid necrosis were 54%, 93%, and 75%, respectively, for reader 1 and 62%, 93%, and 78% for reader 2. Interreader reliability was excellent (κ = 0.92). The A(z) was 0.82 for reader 1 and 0.87 for reader 2. The diagnostic performance of dynamic gadolinium-enhanced MR imaging, determined with the steepest upslope value, was inferior to that of standard MR imaging, with an A(z) of 0.57. Findings at histologic examination (viable bone, necrotic bone, callus formation) did not correlate with those at dynamic gadolinium-enhanced MR imaging. Because the diagnostic performance of dynamic gadolinium-enhanced MR imaging in the evaluation of scaphoid viability was inferior to that of a standard MR imaging protocol, dynamic acquisition may not be needed in patients with nonunion of scaphoid fractures.

Purpose: The aim of this study was to compare qualitative and quantitative image quality and geometric distortion of 4 magnetic resonance diffusion-weighted imaging (DWI) sequences of the prostate using comparable imaging parameters and similar acquisition times. Methods and Materials: Axial T2-weighted turbo spin echo images and axial DWI echo-planar imaging (EPI) sequences, including single-shot spin-echo (ss-EPI), readout-segmented multishot (rs-EPI), selective excitation–reduced field of view (sTX-EPI), and prototype single-shot technique applying slice-specific shimming (iShim-EPI) sequences, were acquired at 3 T in 10 healthy volunteers (mean age, 26.1 ± 3.8 years; body mass index, 23.2 ± 3.0 kg/m²). Two radiologists, blinded to the type of DWI, independently rated DWIs on a 5-point Likert scale regarding subjective image quality features (resolution, demarcation of prostate capsule, zonal anatomy). Interreader agreement was assessed using the intraclass correlation coefficient. Signal-to-noise ratio (SNR) and apparent diffusion coefficient (ADC) values were assessed separately in the peripheral and transitional zone. For the analysis of geometric distortion, the diameter of the prostate from left to right and from anterior to posterior was measured at the level of the verumontanum on b-1000 DWIs and on T2-weighted turbo spin echo images. Differences were compared using the Wilcoxon rank sum test for qualitative parameters, analysis of variance, and Friedman test for quantitative parameters. A P value of less than 0.05 was considered significant, with correction for multiple comparisons. Results: Interreader agreement was good to excellent (intraclass correlation coefficient, 0.71–0.79) for all qualitative features. Subjective image quality regarding “resolution” was significantly better for ss-EPI than rs-EPI (mean Likert score, 4.25 vs 3.8; P = 0.031) and sTX-EPI (4.25 vs 3.3; P = 0.046) and for iShim-EPI as compared with rs-EPI (4.4 vs 3.8; P = 0.031) and sTX-EPI (4.4 vs 3.3; P = 0.047). There was no significant difference regarding capsule demarcation and zonal anatomy. Signal-to-noise ratio was significantly higher in iShim-EPI than sTX-EPI (SNR ± standard deviation [SD], 28.13 ± 8.21 vs 14.96 ± 2.4; P = 0.015). The ADC values were lower for the peripheral zone in the sTX-EPI than in the ss-EPI (ADC ± SD, 1002.94 ± 83.51 vs 1165.05 ± 115.64; P = 0.013) and the rs-EPI (1002.94 ± 83.51 vs 1244.40 ± 89.95; P = 0.0012) and in the transitional zone in the sTX-EPI compared with the rs-EPI (874.50 ± 200.72 vs 1261.47 ± 179.23; P = 0.0021). There were no statistically significant differences in geometric distortion between all DWI sequences. Conclusions: Single-shot spin-echo EPI and iShim-EPI showed a tendency toward superior image quality and SNR compared with rs-EPI and sTX-EPI with no significant differences in geometric distortion.

Comparing mpMRI and ⁶⁸Ga-PSMA-PET/MRI in primary staging of PCa and investigating the value of quantitative mpMRI-measurements for prediction of extracapsular extension and N-metastases. Patients with PCa undergoing ⁶⁸Ga-PSMA-PET/MRI and mpMRI during January 2016 to February 2019 were retrospectively included. Two readers each on ⁶⁸Ga-PSMA-PET/MRI or mpMRI rated extraprostatic extension (≥T3) and regional lymph-node-metastasis (N1) on a Likert-scale. A fifth reader measured tumor volume, maximum diameter, and capsular contact length on mpMRI. Probability of lymph-node-metastasis was additionally calculated using the 2018 Briganti model. Interobserver-agreement was assessed by squared Cohen's kappa, and diagnostic accuracy was determined using radical prostatectomy (n = 35/49) as reference standard. 49 patients (median age 66 years [IQR: 61-72 years]) were evaluated. Interobserver-agreement for mpMRI and ⁶⁸Ga-PSMA-PET/MRI was: ≥T3: κ = 0.58/0.47; N1: κ = 0.55/0.92. Diagnostic accuracy for mpMRI vs ⁶⁸Ga-PSMA-PET/MRI readers for ≥ T3 was AUC: 0.72, 0.62 vs 0.71, 0.72 (p > 0.38) and for N1 was AUC: 0.39, 0.55 vs 0.72, 0.78 (p < 0.01). Quantitative parameters delivered diagnostic accuracies of: AUC: 0.70-0.72 for ≥ T3. The 2018 Briganti model achieved an AUC of 0.89 for N1. Interreader-agreement regarding ≥ T3 was similar for mpMRI and ⁶⁸Ga-PSMA-PET/MRI while for N1 it was higher for ⁶⁸Ga-PSMA-PET/MRI. Diagnostic accuracy was comparable for ≥ T3 while for N1 it was higher in ⁶⁸Ga-PSMA-PET/MRI and the 2018 Briganti model. Combining clinical data and quantitative data from mpMRI in the 2018 Briganti model yielded the highest AUC for prediction of lymph node metastasis and may aid in selecting patients who will benefit from ⁶⁸Ga-PSMA-PET/MRI for primary staging.