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Objectives: To compare 0.15 mmol/kg gadobutrol for late gadolinium enhancement (LGE) imaging of chronic myocardial infarction with a relaxivity-adjusted dose of gadoterate meglumine (Gd-DOTA).Methods: Seventeen patients with suspected chronic myocardial infarction underwent LGE imaging at 1.5 T, acquiring an inversion-recovery-prepared gradient echo sequence 15 min after contrast agent administration. Each patient underwent LGE imaging twice, once after administration of 0.15 mmol/kg gadobutrol (r1 = 5.2 l mmol(-1) s(-1)) and after 0.22 mmol/kg Gd-DOTA (r1 = 3.6 l mmol(-1) s(-1)). Two readers independently determined infarct size and contrast-to-noise ratios of infarcted myocardium to remote myocardium (CNR(remote)) and to the left ventricular lumen (CNR(lumen)).Results: LGE was present in 14 patients. Infarct sizes determined after administration of gadobutrol [23.4 ml; 95 % CI (14.4; 32.5)] and Gd-DOTA [22.1 ml; 95 % CI (13.0; 31.1)] were not statistically different (P = 0.22). The CNR(remote) of LGE in infarcted myocardium on gadobutrol- and Gd-DOTA-enhanced images was 44.1 [95 % CI (31.0; 57.1)] and 45.2 [95 % CI (32.2; 58.3)], respectively (P = 0.73). CNR(lumen) was significantly higher on gadobutrol-enhanced LGE images [12.7; 95 % CI (2.5; 23.0) versus 6.8; 95 % CI (-3.5; 17.0); P = 0.02].Conclusion: At relaxivity-adjusted doses, gadobutrol and Gd-DOTA yielded similar infarct sizes with superior contrast between infarcted myocardium and left ventricular lumen on gadobutrol-enhanced images. [ABSTRACT FROM AUTHOR]

Objectives: Assessment of cartilage lesions and osteoarthritis (OA) of the patellofemoral joint in patients following lateral patellar dislocation using magnetic resonance imaging (MRI).Methods: MR images of 129 knees (mean age 26 years, range 11-56) grouped as acute (A), recurrent (B), and chronic (C) dislocators were analysed regarding the prevalence and severity of patellofemoral cartilage lesions. Grades of OA were assessed using modified WORMS.Results: In groups A, B, and C the prevalence of cartilage lesions was 71%, 82%, and 97%, respectively. Most lesions were located on the central patella in groups A and B (central 69% and 78%; medial 56% and 47%; lateral 31% and 42%), whereas group C revealed all regions affected (73%, 61%, and 67%). Of group A, 14% had mild OA and 64% of group B. Group C showed mild OA in 62% and moderate OA in 18%. Cartilage defect size and prevalence of OA was correlated with number of dislocations (r = 0.41 and r = 0.59; P < 0.001).Conclusions: Cartilage lesions and early OA are common after patellar dislocation and appear to increase with the frequency of dislocation. Both conditions should be considered when interpreting MRI in such patients, because of implications for treatment.Key Points: • Cartilage lesions are very common after patellar dislocation. • The severity of cartilage lesions increases with number of dislocations. • Osteoarthritis is common after recurrent patellar dislocation, even in young patients. • Detecting cartilage lesions is important after patellar dislocation. [ABSTRACT FROM AUTHOR]

Objectives: To investigate image quality of triple-rule-out (TRO) computed tomography (CT) using a 320-row-detector CT system with substantially reduced contrast medium volume at 100 kV.Methods: Forty-six consecutive patients with noncritical, acute chest pain underwent 320-row-detector CT using a two-step TRO protocol consisting of a non-spiral, non-gated chest CT acquisition (150 mA) followed by a non-spiral, electrocardiography-gated cardiac acquisition (200-500 mA based on body mass index (BMI)). Data were acquired using a biphasic injection protocol with a total iodinated contrast medium volume of 60 ml (370 mg/ml). Vessel attenuation and effective doses were recorded. Image quality was scored independently by two readers.Results: Mean attenuation was 584 ± 114 Hounsfield units (HU) in the ascending aorta, 335 ± 63HU in the aortic arch, 658 ± 136HU in the pulmonary trunk, and 521 ± 97HU and 549 ± 102HU in the right and left coronary artery, respectively. In all but one patient, attenuation and image quality allowed accurate visualization of the pulmonary arteries, thoracic aorta, and coronary arteries in a single examination. Ninety-six percent of all coronary artery segments were rated diagnostic. Radiation exposure ranged between 2.0 and 3.3 mSv.Conclusion: Using 320-row-detector CT the investigated low-dose TRO protocol resulted in excellent opacification and image quality with substantial reduction of contrast medium volume compared to recently published TRO protocols. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the role of MRI in diagnosing acute myocarditis by correlation with immunohistological parameters.Methods: A total of 131 patients (85 men, 46 women; mean age, 44.9 years) with suspected acute myocarditis were examined by MRI. The relative water content of the left ventricular myocardium as well as relative and late enhancement was correlated with the immunohistological results in biopsy specimens.Results: Myocardial inflammation was confirmed by immunohistology in 82 of the 131 patients investigated and ruled out in 49 patients. The sensitivity, specificity and accuracy for diagnosing myocarditis in patients with immunohistologically proven disease were 48.8%, 73.8% and 57.3%, respectively, for relative enhancement, 58.3%, 57.1% and 57.9% for relative water content, and 30.6%, 88.1% and 49.6% for late enhancement. A combination of all three parameters had 39,3% sensitivity and 91,3% specificity and 62,7% accuracy. Relative enhancement and late enhancement significantly correlated with the presence of myocarditis but relative oedema did not.Conclusion: Relative and late enhancement significantly correlate with the presence of myocarditis, while there is no significant correlation for relative oedema. Myocarditis cannot be reliably diagnosed using any of the three MRI parameters alone but combinations of parameters will improve specificity. [ABSTRACT FROM AUTHOR]

Dynamic contrast-enhanced MRI enables noninvasive analysis of prostate vascularization as well as tumour angiogenesis and capillary permeability characteristics in prostate cancers. Pharmacokinetic models summarizing the complex information provided by signal intensity-time curves for a few quantitative pharmacokinetic parameters are increasingly being used in the routine clinical setting. This review consists of two parts. The first part discusses the advantages and disadvantages of the MR pulse sequences that can be used for performing DCE-MRI and also of the most widely used pharmacokinetic parameters and models and the parameters they describe. The second part outlines the range of current and potential future clinical applications of DCE-MRI and pharmacokinetic parametric maps in patients with prostate cancer, with reference to the current scientific literature on the topic. The potential clinical applications of DCE-MRI for prostate cancer include detection, localization, and staging, differentiation of recurrent cancer and estimation of the patient's prognosis, as well as monitoring of treatment response. [ABSTRACT FROM AUTHOR]

Objective: Coronary angiography using multidetector computed tomography (MDCT) allows non-invasive assessment of non-calcified, calcified and mixed plaques. Progression of coronary plaques may be influenced by statins.Methods: Sixty-three consecutive patients underwent MDCT as a follow-up to their original CT angiography in a retrospective longitudinal study. MDCT was performed by using a voxel size of 0.5 × 0.35 × 0.35 mm(3) at two time points 25 ± 3 months apart. Non-calcified, calcified and mixed coronary plaque components were analysed by using volumetric measurement. The influence of statin, low-density lipoprotein (LDL) and risk factors was assessed by using a linear random intercept model for plaque growth.Results: The volumes of non-calcified, calcified and mixed coronary plaques significantly (P < 0.001) increased from baseline (medians/interquartile ranges = 21/15-39, 7/3-20 and 36/16-69 mm(3)) to follow-up (29/17-44, 13/6-29 and 41/20-75 mm(3)). Statins significantly slowed the growth of non-calcified plaques (statin coefficient β = -0.0036, P = 0.01) but did not significantly affect the growth rate of mixed or calcified plaques. The effect of statin treatment on non-calcified plaques remained significant after adjusting for LDL levels and cardiac risk factors.Conclusion: Quantification using MDCT shows that progression of non-calcified coronary plaques may be slowed by statins. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the feasibility and safety of a novel LITT applicator for thermal ablation of liver malignancies in 1.0-T high-field open MRI.Methods: A miniaturised 6-F double-tubed protective catheter with a closed cooling circuit was used with a flexible laser fibre, connected to a 1,064-nm Nd:YAG laser and evaluated in non-perfused porcine livers (18-30 W for 10-20 min, 2-W and 2-min increments; n = 210/applicator) in reference to an established 9-F system. As a proof of concept, MR-guided LITT was performed in two healthy domestic pigs in high-field open MRI.Results: Ex-vivo, the coagulation volumes induced by the 6-F system with maximum applicable power of 24 W for 20 min (33.0 ± 4.4 cm(3)) did not differ significantly from those set with the 9-F system at 30 W for 20 min (35.8 ± 4.9 cm(3)) (p = 0.73). A flow-rate of 15 ml/min of the cooling saline solution was sufficient. MR navigation and thermometry were feasible.Conclusion: The miniaturised 6-F applicator can create comparable coagulation sizes to those of the 9-F system. Applicator guidance and online-thermometry in high-field open MRI are feasible. [ABSTRACT FROM AUTHOR]

Objective: To assess reduced volumes of contrast agent on image quality for coronary computed tomography angiography (CCTA) by using single-beat cardiac imaging with 320-slice CT.Materials and Methods: Forty consecutive male patients (mean age: 55.8 years) undergoing CCTA with body weight or=55% were included. Image acquisition protocol was standardized (120 kV, 400 mA, and prospective ECG-triggered single-beat nonspiral CCTA). Patients were randomly assigned to one of four groups (G1: received 40 ml, G2: 50 ml, G3: 60 ml, G4: 70 ml). Groups were compared with respect to aortic attenuation, image noise, and image quality.Results: CT values (mean +/- standard deviation) in the aortic root were measured as 423 +/- 38 HU in G1, and 471 +/- 68, 463 +/- 60, and 476 +/- 78 HU in G2-4, respectively. There were no statistically significant differences in attenuation among the groups (P > 0.068). All 40 CT datasets were rated diagnostic, and image noise and image quality were not statistically different among groups.Conclusion: Using 320-slice volume CT, diagnostic image quality can be achieved with 40 ml of contrast material in CCTA in patients with normal body weight, cardiac function, and low heart rate. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the accuracy of MDCT for preoperative assessment of hepatic vascular anatomy and the identification of liver-transplantation (OLT) patients at risk of developing subsequent splenic artery steal syndrome (SASS). A total of 145 patients with liver cirrhosis who had undergone OLT and had pre-operative three-phase MDCT (4- to 64-rows) within 100 days before OLT were enrolled retrospectively. MDCT and 3Ds were reviewed by two independent blinded observers (O1/O2). Pre-operative imaging findings were correlated with intra-operative results; findings indicative for SASS were correlated with clinical data and DSA. Among all 145 patients, 16 patients (11%) showed accessory hepatic arteries (accuracy O1/O2, 97%; with 3Ds, 100%); 32 (22%) patients had replaced hepatic arteries (accuracy O1, 97%; O2, 95%; with 3Ds, 100%; kappa = 0.87 and 0.89, P < 0.001). Among 119 patients, 12 patients developed SASS after OLT. The logistic regression model revealed the spleen volume (P = 0.0105) as a predictive factor of SASS. With spleen volumes >or=829 ml, an accuracy of 75% for prediction of SASS was obtained. MDCT with three-dimensional post-processing (3Ds) was highly accurate for pre-operative hepatic vessel evaluation in patients before OLT. In addition, spleen volume was a predictive factor for developing SASS after OLT. [ABSTRACT FROM AUTHOR]

This study was performed to prospectively compare multidetector computed tomography (MDCT) with 16 simultaneous sections and magnetic resonance imaging (MRI) for the assessment of global right ventricular function in 50 patients. MDCT using a semiautomatic analysis tool showed good correlation with MRI for end-diastolic volume (EDV, r=0.83, p<0.001), end-systolic volume (ESV, r=0.86, p<0.001) and stroke volume (SV, r=0.74, p<0.001), but only a moderate correlation for the ejection fraction (EF, r=0.67, p<0.001). Bland Altman analysis revealed a slight, but insignificant overestimation of EDV (4.0 ml, p=0.08) and ESV (2.4 ml, p=0.07), and underestimation of EF (0.1%, p=0.92) with MDCT compared with MRI. All limits of agreement between both modalities (EF: +/-15.7%, EDV: +/-31.0 ml, ESV: +/-18.0 ml) were in a moderate but acceptable range. Interobserver variability of MDCT was not significantly different from that of MRI. For MDCT software, the post-processing time was significantly longer (19.6+/-5.8 min) than for MRI (11.8+/-2.6 min, p<0.001). Accurate assessment of right ventricular volumes by 16-detector CT is feasible but still rather time-consuming. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess a possible association between breast malignancy and ipsilateral higher vascularity on gadolinium-enhanced MR angiography. One hundred six patients were examined by dynamic gadolinium-enhanced 3D MR imaging. Magnetic resonance angiographic views were generated by image subtraction and maximum intensity projection. The study included 85 patients with unilateral malignant breast neoplasms and 21 with unilateral benign lesions. Three blinded readers independently reviewed the MR angiograms after masking the lesions and the corresponding contralateral sites. The readers were asked to determine whether vascularity was higher on the right side, higher on the left side, or equal on both sides. The results were analyzed by the Kappa statistic and Pearson's chi-square test. The blood vessels of the breasts were clearly seen in all cases. There was good agreement among the observers (kappa > 0.54) in assessing vascularity on both sides. Breasts harboring malignant neoplasms were found to have a higher vascularity than the contralateral breasts (p < 0.005). This sign of malignancy had a sensitivity of 76.5%, a specificity of 57%, and an accuracy of 72.6%. Blood vessels of the breast can be depicted by MR angiography. Unilateral malignant neoplasms are associated with a higher ipsilateral vascularity. In conjunction with other indications of malignancy on gadolinium-enhanced MR images, a higher ipsilateral vascularity may serve as an additional sign of malignancy. [ABSTRACT FROM AUTHOR]

Objectives: To develop and test zone-specific prostate-specific antigen density (sPSAD) combined with PI-RADS to guide prostate biopsy decision strategies (BDS)., Methods: This retrospective study included consecutive patients, who underwent prostate MRI and biopsy (01/2012-10/2018). The whole gland and transition zone (TZ) were segmented at MRI using a retrained deep learning system (DLS; nnU-Net) to calculate PSAD and sPSAD, respectively. Additionally, sPSAD and PI-RADS were combined in a BDS, and diagnostic performances to detect Grade Group ≥ 2 (GG ≥ 2) prostate cancer were compared. Patient-based cancer detection using sPSAD was assessed by bootstrapping with 1000 repetitions and reported as area under the curve (AUC). Clinical utility of the BDS was tested in the hold-out test set using decision curve analysis. Statistics included nonparametric DeLong test for AUCs and Fisher-Yates test for remaining performance metrics., Results: A total of 1604 patients aged 67 (interquartile range, 61-73) with 48% GG ≥ 2 prevalence (774/1604) were evaluated. By employing DLS-based prostate and TZ volumes (DICE coefficients of 0.89 (95% confidence interval, 0.80-0.97) and 0.84 (0.70-0.99)), GG ≥ 2 detection using PSAD was inferior to sPSAD (AUC, 0.71 (0.68-0.74)/0.73 (0.70-0.76); p < 0.001). Combining PI-RADS with sPSAD, GG ≥ 2 detection specificity doubled from 18% (10-20%) to 43% (30-44%; p < 0.001) with similar sensitivity (93% (89-96%)/97% (94-99%); p = 0.052), when biopsies were taken in PI-RADS 4-5 and 3 only if sPSAD was ≥ 0.42 ng/mL/cc as compared to all PI-RADS 3-5 cases. Additionally, using the sPSAD-based BDS, false positives were reduced by 25% (123 (104-142)/165 (146-185); p < 0.001)., Conclusion: Using sPSAD to guide biopsy decisions in PI-RADS 3 lesions can reduce false positives at MRI while maintaining high sensitivity for GG ≥ 2 cancers., Clinical Relevance Statement: Transition zone-specific prostate-specific antigen density can improve the accuracy of prostate cancer detection compared to MRI assessments alone, by lowering false-positive cases without significantly missing men with ISUP GG ≥ 2 cancers., Key Points: • Prostate biopsy decision strategies using PI-RADS at MRI are limited by a substantial proportion of false positives, not yielding grade group ≥ 2 prostate cancer. • PI-RADS combined with transition zone (TZ)-specific prostate-specific antigen density (PSAD) decreased the number of unproductive biopsies by 25% compared to PI-RADS only. • TZ-specific PSAD also improved the specificity of MRI-directed biopsies by 9% compared to the whole gland PSAD, while showing identical sensitivity., (© 2024. The Author(s).)

Objectives: Diagnostic performance of imaging for regional lymph node assessment in gastric cancer is still limited, and there is a lack of consensus on radiological evaluation. At the same time, there is an increasing demand for structured reporting using Reporting and Data Systems (RADS) to standardize oncological imaging. We aimed at investigating the diagnostic performance of Node-RADS compared to the use of various individual criteria for assessing regional lymph nodes in gastric cancer using histopathology as reference., Methods: In this retrospective single-center study, consecutive 91 patients (median age, 66 years, range 33-91 years, 54 men) with CT scans and histologically proven gastric adenocarcinoma were assessed using Node-RADS assigning scores from 1 to 5 for the likelihood of regional lymph node metastases. Additionally, different Node-RADS criteria as well as subcategories of altered border contour (lobulated, spiculated, indistinct) were assessed individually. Sensitivity, specificity, and Youden's index were calculated for Node-RADS scores, and all criteria investigated. Interreader agreement was calculated using Cohen's kappa., Results: Among all criteria, best performance was found for Node-RADS scores ≥ 3 and ≥ 4 with a sensitivity/specificity/Youden's index of 56.8%/90.7%/0.48 and 48.6%/98.1%/0.47, respectively, both with substantial interreader agreement (κ = 0.73 and 0.67, p < 0.01). Among individual criteria, the best performance was found for short-axis diameter of 10 mm with sensitivity/specificity/Youden's index of 56.8%/87.0%/0.44 (κ = 0.65, p < 0.01)., Conclusion: This study shows that structured reporting of combined size and configuration criteria of regional lymph nodes in gastric cancer slightly improves overall diagnostic performance compared to individual criteria including short-axis diameter alone. The results show an increase in specificity and unchanged sensitivity., Clinical Relevance Statement: The results of this study suggest that Node-RADS may be a suitable tool for structured reporting of regional lymph nodes in gastric cancer., Key Points: • Assessment of lymph nodes in gastric cancer is still limited, and there is a lack of consensus on radiological evaluation. • Node-RADS in gastric cancer improves overall diagnostic performance compared to individual criteria including short-axis diameter. • Node-RADS may be a suitable tool for structured reporting of regional lymph nodes in gastric cancer., (© 2023. The Author(s).)

Objectives: Differentiation between high-grade glioma (HGG) and post-treatment-related effects (PTRE) is challenging, but advanced imaging techniques were shown to provide benefit. We aim to investigate microstructure characteristics of metabolic compartments identified from amino acid PET and to evaluate the diagnostic potential of this multimodal and integrative O-(2- 18 F-fluoroethyl)-L-tyrosine-(FET)-PET and fast diffusion kurtosis imaging (DKI) approach for the detection of recurrence and IDH genotyping., Methods: Fifty-nine participants with neuropathologically confirmed recurrent HGG (n = 39) or PTRE (n = 20) were investigated using static 18 F-FET PET and a fast-DKI variant. PET and advanced diffusion metrics of metabolically defined (80-100% and 60-75% areas of 18 F-FET uptake) compartments were assessed. Comparative analysis was performed using Mann-Whitney U tests with Holm-Šídák multiple-comparison test and Wilcoxon signed-rank test. Receiver operating characteristic (ROC) curves, regression, and Spearman's correlation analysis were used for statistical evaluations., Results: Compared to PTRE, recurrent HGG presented increased 18 F-FET uptake and diffusivity (MD60), but lower (relative) mean kurtosis tensor (rMKT60) and fractional anisotropy (FA60) (respectively p < .05). Diffusion metrics determined from the metabolic periphery showed improved diagnostic performance - most pronounced for FA60 (AUC = 0.86, p < .001), which presented similar benefit to 18 F-FET PET (AUC = 0.86, p < .001) and was negatively correlated with amino acid uptake (rs =  - 0.46, p < .001). When PET and DKI metrics were evaluated in a multimodal biparametric approach, TBRmax + FA60 showed highest diagnostic accuracy (AUC = 0.93, p < .001), which improved the detection of relapse compared to PET alone (difference in AUC = 0.069, p = .04). FA60 and MD60 distinguished the IDH genotype in the post-treatment setting., Conclusion: Detection of glioma recurrence benefits from a multimodal and integrative PET/DKI approach, which presented significant diagnostic advantage to the assessment based on PET alone., Clinical Relevance Statement: A multimodal and integrative 18 F-FET PET/fast-DKI approach for the non-invasive microstructural characterization of metabolic compartments provided improved diagnostic capability for differentiation between recurrent glioma and post-treatment-related changes, suggesting a role for the diagnostic workup of patients in post-treatment settings., Key Points: • Multimodal PET/MRI with integrative analysis of 18 F-FET PET and fast-DKI presents clinical benefit for the assessment of CNS cancer, particularly for the detection of recurrent high-grade glioma. • Microstructure markers of the metabolic periphery yielded biologically pertinent estimates characterising the tumour microenvironment, and, thereby, presented improved diagnostic accuracy with similar accuracy to amino acid PET. • Combined 18 F-FET PET/fast-DKI achieved the best diagnostic performance for detection of high-grade glioma relapse with significant benefit to the assessment based on PET alone., (© 2023. The Author(s).)