MR-Guided Transurethral Ultrasound Ablation of Prostate Cancer: Initial Experience of Monitoring Tumor Response by Dynamic Apparent Diffusion Coefficient Measurements at 3.0 T.

INTRODUCTION: Diffusion-weighted imaging (DWI) as part of multiparametric magnetic resonance imaging (mpMRI) is an important sequence for the detection of prostate cancer (PCa). The objective of this retrospective analysis was to evaluate changes in apparent diffusion coefficient (ADC) measurements in biopsy-proven PCa undergoing TULSA-PRO (MR-guided transurethral ultrasound ablation of the prostate) at 3.0 T after 1, 3, and 6-12 months posttreatment. METHODS: Nineteen patients underwent follow-up examinations after 1, 3, and 6-12 months including mpMRI at 3.0 T and urological-clinical examinations with quantitative analysis of ADCs. RESULTS: In PCa, a significant increase of ADC values after 6-12 months was measured after TULSA-PRO treatment by 29.1% (pre-TULSA: 0.79 ± 0.16 × 10-3 mm2/s, 6-12 months: 1.02 ± 0.35 × 10-3 mm2/s), while the corresponding value in the reference tissue decreased by 48.5% (pre-TULSA: 1.20 ± 0.15 × 10-3 mm2/s, 6-12 months: 0.91 ± 0.29 × 10-3 mm2/s). The mean ADC values in the early follow-up groups at 1 and 3 months did not change significantly. CONCLUSION: DWI with ADC as part of mpMRI can serve as a biomarker to dynamically monitor the follow-up after TULSA after 6-12 months. For early posttreatment progression, it is not suitable due to too many confounding variables.

Concepts in the Establishment of Interdisciplinary Ultrasound Centers: The Role of Radiology. / Konzepte im Aufbau von interdisziplinären Ultraschallzentren: Die Rolle der Radiologie.

BACKGROUND: Ultrasound (US) is widely used as a fast and cost-efficient first-choice imaging technique without relevant side effects for a variety of diagnostic tasks. Due to technical advances, more complex and sophisticated methods such as color-coded duplex ultrasound, image fusion, contrast-enhanced ultrasound (CEUS), and ultrasound-guided interventions have become increasingly important in diagnostic algorithms. METHOD: This study presents an overview of all aspects regarding the establishing of an interdisciplinary US center based on five representative examples in Germany. These aspects include topics of ultrasound education, research, economics, and administration. RESULTS: The goal of an interdisciplinary US center is to bundle the use of equipment, staff, rooms, and infrastructure resources (optimization of equipment availability and use of new techniques) to expand the range of examinations, to promote resident training, and to boost continuing medical education of residents. This should result in better patient care and has additionally improved patient care while considering the added value for the participating institutions involved. Interdisciplinary US centers allow a reduction of the number of US devices needed in a hospital and more efficient use of available equipment through bedside time optimization by central organization within interdisciplinary management. The focused application of special US techniques such as CEUS or image fusion for complex, difficult interventions as well as the training and education of younger colleagues in using these techniques is centrally organized by experts and can be improved through the multidisciplinary experience available. CONCLUSION: Organizational structures, sharing of materials, and standardization of diagnostic reports facilitate and accelerate cooperation with the referring specialty. KEY POINTS: · Interdisciplinary US centers foster clinical collaboration, research, and jointly organized, standardized training.. · Economic aspects include optimization of available equipment, use of the latest US techniques, and centralization of organizational structures.. · Common terminology and standardized reporting increase the satisfaction of referring doctors. CITATION FORMAT: · Clevert DA, Jung EM, Weber M et al. Concepts in the Establishment of Interdisciplinary Ultrasound Centers: The Role of Radiology. Fortschr Röntgenstr 2022; 194: 1322 - 1332.

Effect of Contrast Agent Dose Reduction on Vascular Enhancement and Image Quality in Thoracoabdominal Dynamic 3-Dimensional Magnetic Resonance Angiography: A Systematic Intraindividual Analysis in Pigs.

OBJECTIVE: High spatial and temporal resolution contrast-enhanced magnetic resonance angiography (MRA) with gadolinium-based contrast agents (GBCAs) at standard dose offers both detailed anatomic information on both arterial and venous vessels and hemodynamic characteristics. Several preclinical and clinical dynamic 3-dimensional (3D) MRA studies that focused on arterial vessels only proposed that high image quality may also be achieved with significantly reduced GBCA doses, calling into question the need to use standard doses. A systematic analysis of GBCA doses and resulting image quality for both arteries and veins has not yet been performed. The purpose of this study was therefore to systematically analyze dose-dependent vascular enhancements in dynamic 3D-MRA of the thoracoabdominal vasculature at 1.5 T in an animal model to determine the optimal contrast agent protocol for optimized vascular assessment. MATERIALS AND METHODS: The vascular enhancement in thoracoabdominal dynamic 3D-MRA (time-resolved angiography with interleaved stochastic trajectories, TWIST at 1.5 T) was interindividually and intraindividually compared in 5 anesthetized Göttingen minipigs using gadobutrol at the standard dose (0.1 mmol/kg body weight, ie, 0.1 mL/kg) and at reduced doses (0.08, 0.06, 0.04, 0.02 mmol/kg) in a randomized order. All injections were performed at 2 mL/s followed by 20 mL saline. Images were quantitatively analyzed, measuring signal intensities in 5 regions that covered the passage of the GBCA through the body at different representative stages of circulation (pulmonary, arterial, and venous system). The evaluation of GBCA dose-dependent signal intensity changes in the different vascular regions was performed by linear regression analysis.The qualitative image analysis of dynamic 3D-MRA by 3 independent radiologists included the visibility of 25 arterial and venous vessel segments at different stages of GBCA passage. Possible quality losses were statistically tested by comparing image quality ratings at the reduced dose with that of the standard dose using Friedman test followed by Dunn post hoc test for multiple comparison. Significance was stated at P < 0.05. RESULTS: Quantitative analysis revealed shorter time-to-peak intervals and bolus durations in line with decreasing GBCA dose and volume in all vessels. Although the peak signal was almost independent of the administered GBCA dose at the level of the pulmonary trunk, a linear signal decrease in the abdominal aorta ( r2 = 0.96), the renal arteries ( r2 = 0.99), the inferior vena cava ( r2 = 0.99), and the portal vein ( r2 = 0.97) was observed. Cumulative analysis of arterial segments revealed significantly lower image quality at doses below 40% of the standard dose, whereas in venous segments, significantly lower image quality was observed at doses below 60% of the standard dose. CONCLUSIONS: In dynamic 3D-MRA at 1.5 T, dose reduction leads to a signal loss that is most pronounced in the venous system and results in significantly lower image quality according to the dose and vessels of interest. Careful dose reduction is thus required according to the specific diagnostic needs. For dynamic 3D-MRA of the arterial and venous system, GBCA doses of at least 60% of the standard dose up to the full dose are preferable, whereas 40% of the standard dose seems feasible if only the arterial system is to be imaged.

Antibody-mediated procoagulant platelets in SARS-CoV-2-vaccination associated immune thrombotic thrombocytopenia.

The COVID-19 pandemic has resulted in significant morbidity and mortality worldwide. To prevent severe infection, mass COVID-19 vaccination campaigns with several vaccine types are currently underway. We report pathological and immunological findings in 8 patients who developed vaccine-induced immune thrombotic thrombocytopenia (VITT) after administration of SARS-CoV-2 vaccine ChAdOx1 nCoV-19. We analyzed patient material using enzyme immune assays, flow cytometry and heparin-induced platelet aggregation assay and performed autopsies on two fatal cases. Eight patients (5 female, 3 male) with a median age of 41.5 years (range, 24 to 53) were referred to us with suspected thrombotic complications 6 to 20 days after ChAdOx1 nCoV-19 vaccination. All patients had thrombocytopenia at admission. Patients had a median platelet count of 46.5 x109/L (range, 8 to 92). Three had a fatal outcome and 5 were successfully treated. Autopsies showed arterial and venous thromboses in various organs and the occlusion of glomerular capillaries by hyaline thrombi. Sera from VITT patients contain high titer antibodies against platelet factor 4 (PF4) (OD 2.59±0.64). PF4 antibodies in VITT patients induced significant increase in procoagulant markers (P-selectin and phosphatidylserine externalization) compared to healthy volunteers and healthy vaccinated volunteers. The generation of procoagulant platelets was PF4 and heparin dependent. We demonstrate the contribution of antibody-mediated platelet activation in the pathogenesis of VITT.

Synovial inflammation analyzed by 3-T magnetic resonance imaging in etanercept-treated patients with rheumatoid arthritis indicates persistent disease activity despite of clinical remission: A pilot study.

OBJECTIVES: To evaluate joint inflammation using 3-T MRI in rheumatoid arthritis (RA) patients treated with conventional disease modifying anti-rheumatic drugs (cDMARDs) as compared to inhibitors for tumor necrosis factor α (TNFi) over 12 months. METHODS: Prospective epidemiologic clinical pilot study using the RA MRI system (RAMRIS), the visual analog scale (VAS, 0-100) and the Disease Activity Score 28-joint count (DAS28) at baseline, 4, and 12 months after initiation of etanercept (ETA). Ten patients with inadequate response to two cDMARDs were treated with ETA and compared to 10 patients responding to cDMARDs. RESULTS: In cDMARD patients, parameters at baseline and 12 months did not change: VAS: 21.0 ± 11.3 and 20.2 ± 24.6; DAS28: 2.1 ± 0.6 and 2.9 ± 1.0; and RAMRIS: 11.0 ± 2.3 and 11.8 ± 2.8, respectively. In contrast, in the ETA-patients the same parameters were as follows at baseline, 4, and 12 months: VAS: 46.3 ± 7.9, 23.9 ± 7.1, and 24.0 ± 6.3 (each p = .04); DAS28: 3.8 ± 0.4, 2.8 ± 0.3 (ns), and 2.5 ± 0.3 (p = .01); and RAMRIS: 28.9 ± 5.0, 25.8 ± 4.7 (ns), and 24.6 ± 4.5 (ns). Comparing ETA and cDMARD patients, RAMRIS was significantly different. CONCLUSION: The data suggest that synovial inflammation and DAS28 remission are separate entities in RA. MRI scoring before starting a treatment may therefore indicate the requirement for TNFi.

Contrast Media in Time-Resolved MRA at 3T: A Systematic Quantitative and Qualitative Analysis of Concentration and Dose Effects on Image Parameters in Minipigs.

PURPOSE: Quantitative and qualitative analysis of gadopentetate dimeglumine (GD) versus standard-dose (sGb) and half-dose (hGb) gadobutrol in thoracoabdominal time-resolved contrast-enhanced magnetic resonance angiography (4D-MRA) with dynamic computed tomography (dCT) as the quantitative reference in minipigs. MATERIALS AND METHODS: 7 anesthetized Goettingen minipigs received thoracoabdominal dCT (0.37 s rotation time) and transverse 4D-MRA (0.3 s/dynamic frame;) using sGb and hGb. 8 other minipigs received coronal 4D-MRA (1.3 s/dynamic frame; sGb, hGb, SGD). dCT attenuation levels were converted into absolute gadolinium concentrations and compared to 4D-MRA peak signal intensities (SI). Bolus lengths were quantified by full width at half maximum (FWHM) measurements. After this comparison of dose effects on SI in transverse 4D-MRA, coronal 4D-MRAs were analyzed regarding both quantitative and qualitative parameters. RESULTS: In dCT (transverse 4D-MRA) hGb showed 39.0 % (14.5 %) lower arterial peak gadolinium concentrations (peak SIs) and 20.6 % (33.8 %) shorter FWHM compared to sGb. The difference was due to peak plateaus or reversals in 4D-MRA in 5/7 animals. While sGb led to the highest peak SIs, image quality ratings of arteries were rated similarly high with all contrast agent protocols despite a slightly higher SI with sGb. In contrast, venous peak SIs and image quality ratings were significantly higher when using sGb. CONCLUSION: Peak Gd concentrations and 4D-MRA peak SIs are highest with sGB. These differences are most evident in the venous phase leading to superior image quality in multi-phase 4D-MRA. KEY POINTS: · Standard-dose gadobutrol offers high vascular gadolinium concentrations and 4D-MRA peak signals.. · Absolute vascular gadolinium concentrations and 4D-MRA peak signal intensities at 3 T diverge.. · Peak plateaus or reversals cause decreased arterial 4D-MRA peak signals at 3 T.. · Arterial image quality is rated similarly high using different contrast agent protocols.. · Venous vessel visibility in 4D-MRA is significantly better using standard dose gadobutrol.. CITATION FORMAT: · Hadizadeh DR, Keil VC, Jost G et al. Contrast Media in Time-Resolved MRA at 3T: A Systematic Quantitative and Qualitative Analysis of Concentration and Dose Effects on Image Parameters in Minipigs. Fortschr Röntgenstr 2018; 190: 747 - 757.

Characterization of Severe Arterial Phase Respiratory Motion Artifact on Gadoxetate Disodium-Enhanced MRI - Assessment of Interrater Agreement and Reliability.

PURPOSE: To assess the interrater agreement and reliability of experienced abdominal radiologists in the characterization and grading of arterial phase gadoxetate disodium-related respiratory motion artifact on liver MRI. MATERIALS AND METHODS: This prospective multicenter study was initiated by the working group for abdominal imaging within the German Roentgen Society (DRG), and approved by the local IRB of each participating center. 11 board-certified radiologists independently reviewed 40 gadoxetate disodium-enhanced liver MRI datasets. Motion artifacts in the arterial phase were assessed on a 5-point scale. Interrater agreement and reliability were calculated using the intraclass correlation coefficient (ICC) and Kendall coefficient of concordance (W), with p < 0.05 deemed significant. RESULTS: The ICC for interrater agreement and reliability were 0.983 (CI 0.973 - 0.990) and 0.985 (CI 0.978 - 0.991), respectively (both p < 0.0001), indicating excellent agreement and reliability. Kendall's W for interrater agreement was 0.865. A severe motion artifact, defined as a mean motion score ≥ 4 in the arterial phase was observed in 12 patients. In these specific cases, a motion score ≥ 4 was assigned by all readers in 75 % (n = 9/12 cases). CONCLUSION: Differentiation and grading of arterial phase respiratory motion artifact is possible with a high level of inter-/intrarater agreement and interrater reliability, which is crucial for assessing the incidence of this phenomenon in larger multicenter studies. KEY POINTS: · Inter- and intrarater agreement for motion artifact scoring is excellent among experienced readers.. · Interrater reliability for motion artifact scoring is excellent among experienced readers.. · Characterization of severe motion artifacts proved feasible in this multicenter study.. CITATION FORMAT: · Ringe KI, Luetkens JA, Fimmers R et al. Characterization of Severe Arterial Phase Respiratory Motion Artifact on Gadoxetate Disodium-Enhanced MRI - Assessment of Interrater Agreement and Reliability. Fortschr Röntgenstr 2017; 190: 341 - 347.

Influence of Chitosan Treatment on Surrogate Serum Markers of Cholesterol Metabolism in Obese Subjects.

Chitosan treatment results in significantly lower serum low density lipoprotein (LDL) cholesterol concentrations. To assess the working mechanisms of chitosan, we measured serum surrogate markers of cholesterol absorption (campesterol, sitosterol, cholestanol), synthesis (lathosterol, lanosterol, desmosterol), and degradation to bile acids (7α-hydroxy-cholesterol, 27-hydroxy-cholesterol), corrected for cholesterol concentration (R_sterols). Over 12 weeks, 116 obese subjects (Body Mass Index, BMI 31.7, range 28.1-38.9 kg/m²) were studied under chitosan (n = 61) and placebo treatments (n = 55). The participants were briefly educated regarding improvement of nutrition quality and energy expenditure. Daily chitosan intake was 3200 mg. Serum LDL cholesterol concentration decreased significantly more (p = 0.0252) under chitosan (-8.67 ± 18.18 mg/dL, 5.6%) than under placebo treatment (-1.00 ± 24.22 mg/dL, 0.9%). This reduction was not associated with the expected greater decreases in markers of cholesterol absorption under chitosan treatment. Also, increases in markers of cholesterol synthesis and bile acid synthesis under chitosan treatment were not any greater than under placebo treatment. In conclusion, a significant selective reduction of serum LDL cholesterol under chitosan treatment is neither associated with a reduction of serum surrogate markers of cholesterol absorption, nor with increases of markers for cholesterol and bile acid synthesis.

Revised PROPELLER for T2-weighted imaging of the prostate at 3 Tesla: impact on lesion detection and PI-RADS classification.

PURPOSE: To evaluate revised PROPELLER (RevPROP) for T2-weighted imaging (T2WI) of the prostate as a substitute for turbo spin echo (TSE). MATERIALS AND METHODS: Three-Tesla MR images of 50 patients with 55 cancer-suspicious lesions were prospectively evaluated. Findings were correlated with histopathology after MRI-guided biopsy. T2 RevPROP, T2 TSE, diffusion-weighted imaging, dynamic contrast enhancement, and MR-spectroscopy were acquired. RevPROP was compared to TSE concerning PI-RADS scores, lesion size, lesion signal-intensity, lesion contrast, artefacts, and image quality. RESULTS: There were 41 carcinomas in 55 cancer-suspicious lesions. RevPROP detected 41 of 41 carcinomas (100%) and 54 of 55 lesions (98.2%). TSE detected 39 of 41 carcinomas (95.1%) and 51 of 55 lesions (92.7%). RevPROP showed fewer artefacts and higher image quality (each p < 0.001). No differences were observed between single and overall PI-RADS scores based on RevPROP or TSE (p = 0.106 and p = 0.107). Lesion size was not different (p = 0.105). T2-signal intensity of lesions was higher and T2-contrast of lesions was lower on RevPROP (each p < 0.001). CONCLUSION: For prostate cancer detection RevPROP is superior to TSE with respect to motion robustness, image quality and detection rates of lesions. Therefore, RevPROP might be used as a substitute for T2WI. KEY POINTS: • Revised PROPELLER can be used as a substitute for T2-weighted prostate imaging. • Revised PROPELLER detected more carcinomas and more suspicious lesions than TSE. • Revised PROPELLER showed fewer artefacts and better image quality compared to TSE. • There were no significant differences in PI-RADS scores between revised PROPELLER and TSE. • The lower T2-contrast of revised PROPELLER did not impair its diagnostic quality.

Percutaneous Isolated Hepatic Perfusion as a Treatment for Isolated Hepatic Metastases of Uveal Melanoma: Patient Outcome and Safety in a Multi-centre Study.

PURPOSE: Percutaneous isolated hepatic perfusion (PIHP) with Melphalan has been developed as a treatment for patients with isolated hepatic metastases of uveal melanoma. We discuss patient outcome and safety in a retrospective multi-centre study. MATERIALS AND METHODS: Between 2012 and 2016 18 patients with un-resectable isolated hepatic metastases of uveal melanoma received single or repeated PIHP with Melphalan (n = 35) at seven sites. Progression-free time, overall survival time (OS) and tumour response by means of RECIST 1.1 criteria were evaluated. Peri- and post-procedural adverse events (AE) were registered. Patients' life quality was assessed using four-point scale questionnaires. RESULTS: Of 18 patients, initial PIHP treatment resulted in partial response (PR) in eight, stable disease (SD) in seven and progressive disease (PD) in three cases. Nine patients underwent second PIHP with PR in eight cases and PD in one case. Six patients were evaluated after third PIHP with PR in five patients and SD in one patient. Two patients received fourth PIHP with PD in both cases. Median OS was 9.6 months (range 1.6-41.0 months). Median progression-free survival time was 12.4 months (range 0.9-41.0 months) with 1-year survival of 44%. Most common post-procedural AE grade 3 and 4 were temporary leukopenia (n = 11) and thrombocytopenia (n = 8). Patients' self-assessments showed good ratings for overall health and quality of life with only slight changes after PIHP, and a high degree of satisfaction with PIHP treatment. CONCLUSION: PIHP with Melphalan proved to be a relatively safe, minimal-invasive and repeatable treatment for patients with non-resectable hepatic metastases of uveal melanoma.

MRI of the Prostate: Recommendations on Patient Preparation and Scanning Protocol.

The Working Group Uroradiology and Urogenital Diagnosis of the German Roentgen Society has developed uniform recommendations for the preparation and implementation of prostate MRI. In the first part detailed recommendations are given in tabular form regarding 1. anamnestic data before prostate MRI, 2. termination of examinations and preparation of examinations, 3. examination protocol and 4. MRI-guided in-bore biopsy. In the second part, the recommendations are discussed in detail and relevant background information is provided. Key Points: · Uniform recommendations for prostate MRI has been developed from the Working Group Uroradiology and Urogenital Diagnosis of the German Roentgen Society.. · Necessary anamnestic data, recommendations for termination of examinations and prepararion of examinations, examination protocol and MRI guided in-bore biopsy are detailed expressed and documented.. Citation Format · Franiel T., Quentin M., Mueller-Lisse U. G. et al. MRI of the Prostate: Recommendations on Patient Preparation and Scanning Protocol. Fortschr Röntgenstr 2017; 189: 21 - 28.

In-bore transrectal MRI-guided prostate biopsies: Are there risk factors for complications?

PURPOSE: To systematically analyze risk factors for complications of in-bore transrectal MRI-guided prostate biopsies (MRGB). MATERIALS AND METHODS: 90 patients, who were scheduled for MRGB were included for this study. Exclusion criteria were coagulation disorders, therapy with anticoagulant drugs, and acute infections of the urinary and the lower gastrointestinal tract. Directly after, one week and one year after the biopsy, we assessed biopsy related complications (e.g. hemorrhages or signs of prostatitis). Differences between patients with and without complications were analyzed regarding possible risk factors: age, prostate volume, number of taken samples, biopsy duration, biopsy of more than one lesion, diabetes, arterial hypertension, hemorrhoids, benign prostate hyperplasia, carcinoma or prostatitis (according to histopathological analysis), and lesion localization. Complications were classified according to the Clavien-Dindo classification. RESULTS: We observed 15 grade I complications in 90 biopsies (16.7%) with slight hematuria in 9 cases (10%), minor vasovagal reactions in 4 cases (4.4%), and urinary retention and positioning-related facial dysesthesia in 1 case each (1.1%). One patient showed acute prostatitis requiring antibiotics as the only grade II complication (1.1%). There were no adverse events that occurred later than one week. Complications grade III or higher such as pelvic abscesses, urosepsis or severe hemorrhages were not seen. There were no significant associations between the assessed risk factors and biopsy-related complications. CONCLUSION: In-bore transrectal MRI-guided prostate biopsies can be considered safe procedures in the diagnosis of prostate cancer with very low complication rates. There seem to be no risk factors for complications.

Intravoxel incoherent motion model-based analysis of diffusion-weighted magnetic resonance imaging with 3 b-values for response assessment in locoregional therapy of hepatocellular carcinoma.

PURPOSE: The aim of this study was to evaluate an intravoxel incoherent motion (IVIM) model-based analysis of diffusion-weighted imaging (DWI) for assessing the response of hepatocellular carcinoma (HCC) to locoregional therapy. PATIENTS AND METHODS: Respiratory-gated DWI (b=0, 50, and 800 s/mm2) was retrospectively analyzed in 25 patients who underwent magnetic resonance imaging at 1.5 T before and 6 weeks following the first cycle of transarterial chemoembolization therapy, transarterial ethanol-lipiodol embolization therapy, and transarterial radioembolization therapy. In addition to the determination of apparent diffusion coefficient, ADC(0,800), an estimation of the diffusion coefficient, D', and the perfusion fraction, f', was performed by using a simplified IVIM approach. Parameters were analyzed voxel-wise. Tumor response was assessed in a central slice by using a region of interest (ROI) covering the whole tumor. HCCs were categorized into two groups, responders and nonresponders, according to tumor size changes on first and second follow ups (if available) and changes of contrast-enhanced region on the first follow up. RESULTS: In total, 31 HCCs were analyzed: 17 lesions were assigned to responders and 14 were to nonresponders. In responders, ADC(0,800) and D' were increased after therapy by ~30% (P=0.00004) and ~42% (P=0.00001), respectively, whereas f' was decreased by ~37% (P=0.00094). No significant changes were found in nonresponders. Responders and nonresponders were better differentiated by changes in D' than by changes in ADC(0,800) (area under the curve =0.878 vs 0.819 or 0.714, respectively). CONCLUSION: In patients with HCCs undergoing embolization therapy, diffusion changes were better reflected by D' than by conventional ADC(0,800), which is influenced by counteracting perfusion changes as assessed by f'.

Yttrium-90 Radioembolization of Advanced, Unresectable Breast Cancer Liver Metastases-A Single-Center Experience.

PURPOSE: To determine value of transarterial radioembolization (TARE) for palliative treatment of unresectable liver-dominant breast metastases (LdBM) and to determine prognostic parameters. MATERIALS AND METHODS: Records of patients undergoing TARE for progressing LdBM between June 2006 and March 2015 were retrospectively reviewed; 44 female patients (mean age 56.1 y; range, 34.9-85.3 y) underwent 69 TAREs (56 resin-based, 13 glass-based). Of 44 patients, 42 had bilobar disease. Mean administered activity was 1.35 GBq ± 0.71. Median clinical and imaging follow-up times were 121 days (range, 26-870 d; n = 42 patients) and 93 days (range, 26-2,037 d; n = 38 patients). Clinical and biochemical toxicities, imaging response (according to Response Evaluation Criteria In Solid Tumors), time to progression, and overall survival (OS) were evaluated. Data were analyzed with stratification according to clinical and procedural parameters. RESULTS: Toxicities included 1 cholecystitis (grade 2) and 1 duodenal ulceration (grade 3); no grade ≥ 4 clinical toxicities were noted. Objective response rate (complete + partial response) was 28.9% (11/38); disease control rate (response + stable disease) was 71.1% (27/38). Median time to progression of treated liver lobe was 101 days (range, 30-2,037 d). During follow-up, 34/42 patients died (median OS after first TARE: 184 d [range 29-2,331 d]). On multivariate analysis, baseline Eastern Cooperative Oncology Group (ECOG) status of 0 (P < .0001, hazard ratio [HR] = 0.146) and low baseline γ-glutamyltransferase (GGT) levels (P = .0146, HR = 0.999) were predictors of longer OS. CONCLUSIONS: TARE can successfully delay progression of therapy-refractory LdBM with low complication rate. Nonelevated baseline ECOG status and low GGT levels were identified as prognostic factors.

Intravoxel Incoherent Motion Diffusion-Weighted MR Imaging for Prediction of Early Arterial Blood Flow Stasis in Radioembolization of Breast Cancer Liver Metastases.

PURPOSE: To retrospectively evaluate predictive value of intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI) for early arterial blood flow stasis during transarterial radioembolization (TARE) of liver dominant breast metastases (LdBM). MATERIALS AND METHODS: Preinterventional 1.5T DWI (b0, b1, b2 = 0, 50, 800 s/mm(2)) data for 28 liver lobes of 18 female patients treated by resin-based radioembolization (10 bilobar and 8 unilobar treatments) were analyzed. Apparent diffusion coefficient (ADC) (0, 800) and an estimation of the true diffusion coefficient D' and of the perfusion fraction f' were calculated for the 2 largest metastases. Response rate at 3 months and survival were analyzed. Procedures without full dose application because of early stasis were assigned to group A (n = 15), and procedures with full dose application were assigned to group B (n = 13). RESULTS: Metastases in group A showed significantly lower f' (0.035 ± 0.018 vs 0.076 ± 0.015, P < .0001) and a trend toward lower ADC(0, 800) with values given in 10(-6) mm(2)/s (1,066 ± 141 vs 1,189 ± 176, P = .051); no group difference was shown for D'. Groups were best discriminated by weighted mean f' values of the 2 largest metastases with accuracy of 100%. Mean tumor diameter before and after TARE was 51 mm ± 18 and 50 mm ± 24 in group A and 47 mm ± 27 and 48 mm ± 32 for group B. Imaging response did not differ between groups (P = .545). Overall survival did not differ significantly between group A (230 d) and B (155 d) (P = .124). CONCLUSIONS: Perfusion-sensitive IVIM parameter f' may predict early blood flow stasis in patients undergoing TARE for LdBM. Determination of this parameter before intervention may increase awareness of the interventionalist and increase safety of microsphere administration.

Differentiation of prostatitis and prostate cancer using the Prostate Imaging-Reporting and Data System (PI-RADS).

PURPOSE: To determine if prostate cancer (PCa) and prostatitis can be differentiated by using PI-RADS. MATERIALS AND METHODS: 3T MR images of 68 patients with 85 cancer suspicious lesions were analyzed. The findings were correlated with histopathology. T2w imaging (T2WI), diffusion weighted imaging (DWI), dynamic contrast enhancement (DCE), and MR-Spectroscopy (MRS) were acquired. Every lesion was given a single PI-RADS score for each parameter, as well as a sum score and a PI-RADS v2 score. Furthermore, T2-morphology, ADC-value, perfusion type, citrate/choline-level, and localization were evaluated. RESULTS: 44 of 85 lesions showed PCa (51.8%), 21 chronic prostatitis (24.7%), and 20 other benign tissue such as hyperplasia or fibromuscular tissue (23.5%). The single PI-RADS score for T2WI, DWI, DCE, as well as the aggregated score including and not including MRS, and the PI-RADS v2-score were all significantly higher for PCa than for prostatitis or other tissue (p<0.001). The single PI-RADS score for MRS and the PI-RADS sum score including MRS were significantly higher for prostatitis than for other tissue (p=0.029 and p=0.020), whereas the other parameters were not different. Prostatitis usually presented borderline pathological PI-RADS scores, showed restricted diffusion with ADC≥900mm(2)/s in 100% of cases, was more often indistinctly hypointense on T2WI (66.7%), and localized in the transitional zone (57.1%). An ADC≥900mm(2)/s achieved the highest predictive value for prostatitis (AUC=0.859). CONCLUSION: Prostatitis can be differentiated from PCa using PI-RADS, since all available parameters are more distinct in cases of cancer. However, there is significant overlap between prostatitis and other benign findings, thus PI-RADS is only suitable to a limited extent for the primary assessment of prostatitis. Restricted diffusion with ADC≥900mm(2)/s is believed to be a good indicator for prostatitis. MRS can help to distinguish between prostatitis and other tissue.

Safety of gadobutrol in more than 1,000 pediatric patients: subanalysis of the GARDIAN study, a global multicenter prospective non-interventional study.

BACKGROUND: Gadobutrol is a gadolinium-based contrast agent, uniquely formulated at 1.0 mmol/ml. Although there is extensive safety evidence on the use of gadobutrol in adults, few studies have addressed the safety and tolerability of gadobutrol in pediatric patients. OBJECTIVE: This subanalysis of data from the GARDIAN study evaluated the safety and use of gadobutrol in pediatric patients (age <18 years). MATERIALS AND METHODS: The GARDIAN study was a large phase IV non-interventional prospective multicenter post-authorization safety study performed in Europe, Asia, North America and Africa. A total of 23,708 patients were included who were scheduled to undergo cranial or spinal MRI, liver or kidney MRI, or MR angiography with gadobutrol enhancement. The primary study endpoint was the overall incidence of adverse drug reactions (ADRs) and serious adverse events (SAEs) following gadobutrol administration. RESULTS: The GARDIAN study included 1,142 children (age <18 years) who received gadobutrol at a mean dose of 0.13 (range 0.04-0.50) mmol/kg body weight. Gadobutrol was well tolerated in these children, with low rates of ADRs (0.5%) and no SAEs, consistent with results in adults enrolled in the GARDIAN study. Rates of adverse events and ADRs were unrelated to pediatric age or gadobutrol weight-adjusted dose. There were no symptoms suggestive of nephrogenic systemic fibrosis. Investigators rated the contrast quality of gadobutrol-enhanced images as good or excellent in 97.8% of pediatric patients, similar to the main study population. CONCLUSION: Gadobutrol is very well tolerated and provides excellent contrast quality at the recommended weight-adjusted dose in children (age <18 years), similar to the profile in adults.

A new robotic assistance system for percutaneous CT-guided punctures: Initial experience.

PURPOSE: To evaluate the feasibility of CT-guided bone biopsies using a novel robotic needle guide. MATERIAL AND METHODS: The robotic needle guide iSYS 1.3 (iSYS Medzintechnik, GmbH, Kitzbuehel, Austria) mounted on the standard table of a CT scanner was used for all studies. For preclinical testing, eight vertebral bodies of dead swine were biopsied, trying to place the needle in the center of the vertebral body via a transpedicular access. For clinical evaluation, bone biopsies were taken in three different patients with ambiguous bone lesions. All biopsies were performed under general anesthesia, using a 12G bone biopsy needle. RESULTS: The animal studies demonstrated that the biopsy needle could be placed accurately in the center of the vertebral body in all cases. No readjustment was necessary, the CT scans demonstrated an intrapedicular trajectory avoiding the spinal canal or the neural foramina. Subsequently, following the animal studies, all biopsies could be performed successfully. Needle placement was accurate without any need for readjustment. No complications occurred during the procedure. CONCLUSION: Using the iSYS 1.3 allows for accurate and simple stereotactic biopsies of bone lesions, avoiding the need for needle readjustment. The systems may offer even less experienced teams to take biopsies in regions which are difficult to access.

Colonoscopy detects significantly more flat adenomas than 3-tesla magnetic resonance colonography: a pilot trial.

BACKGROUND AND STUDY AIMS: Colorectal cancer (CRC) is one of the most common cancers worldwide, and several efforts have been made to reduce its occurrence or severity. Although colonoscopy is considered the gold standard in CRC prevention, it has its disadvantages: missed lesions, bleeding, and perforation. Furthermore, a high number of patients undergo this procedure even though no polyps are detected. Therefore, an initial screening examination may be warranted. Our aim was to compare the adenoma detection rate of magnetic resonance colonography (MRC) with that of optical colonoscopy. PATIENTS AND METHODS: A total of 25 patients with an intermediate risk for CRC (17 men, 8 women; mean age 57.6, standard deviation 11) underwent MRC with a 3.0-tesla magnet, followed by colonoscopy. The endoscopist was initially blinded to the results of MRC and unblinded immediately after examining the distal rectum. Following endoscopic excision, the size, anatomical localization, and appearance of all polyps were described according to the Paris classification. RESULTS: A total of 93 lesions were detected during colonoscopy. These included a malignant infiltration of the transverse colon due to gastric cancer in 1 patient, 28 adenomas in 10 patients, 19 hyperplastic polyps in 9 patients, and 45 non-neoplastic lesions. In 5 patients, no lesion was detected. MRC detected significantly fewer lesions: 1 adenoma (P = 0.001) and 1 hyperplastic polyp (P = 0.004). The malignant infiltration was seen with both modalities. Of the 28 adenomas, 23 (82 %) were 5 mm or smaller; only 4 adenomas 10 mm or larger (14 %) were detected. CONCLUSION: MRC does not detect adenomas sufficiently independently of the location of the lesion. Even advanced lesions were missed. Therefore, colonoscopy should still be considered the current gold standard, even for diagnostic purposes.