New magnetic resonance imaging (MRI) gradient technology enables the acquisition of ultrahigh b-value diffusion-weighted imaging (DWI). We assessed its impact on image quality and Prostate Imaging Reporting and Data System (PI-RADS) scores in prostate MRI. Participants with cancer suspicion prospectively underwent 3-T prostate MRI (maximum gradient strength 200 mT/m). Sequences with b-values of 0/800, 1,500, 2,500, 3,500, and 4,500 s/mm² were acquired. Lesion conspicuity was rated from 1 (non-diagnostic) to 5 (excellent). Apparent signal-to-noise ratios (aSNR) and acquisition times were determined. Cumulative link mixed-effects models, repeated measures ANOVA, and Cohen/Fleiss κ statistics were used. A total of 107 participants, aged 67 ± 8 years (mean ± standard deviation), were included. Compared to DWI(b1500), the DWI(b2500), DWI(b3500), and DWI(b4500) acquisitions were worse regarding both lesion conspicuity (median score, 5 [interquartile interval 4–5] versus 4 [3–4] versus 2 [2–3] versus 2 [1–2], respectively; all p < 0.001) and aSNR (19.0 ± 7.5 versus 12.7 ± 4.8 versus 11.8 ± 4.1 versus 11.4 ± 2.6, respectively; all p < 0.001). Acquisition times increased from DWI(b1500) (107 ± 9 s) to DWI(b4500) (329 ± 26 s). Cohen κ for PI-RADS score agreement was good to moderate (DWI(b2500): 0.87 [confidence interval 0.81, 0.94]; DWI(b3500): 0.75 [0.65, 0.84]; DWI(4500): 0.61 [0.49, 0.72]). Acquired ultrahigh gradient DWI sequences with ultrahigh b-values in prostate MRI had worse image quality than standard b-values, while PI-RADS agreement between DWI(b1500) and DWI(b2500) was good. However, diagnostic estimates for clinically significant prostate carcinoma remained limited due to a small biopsy sample size (50/107 patients). Ultrahigh b-value DWI showed no improved diagnostic performance in comparison to standard b-value DWI regarding the identification of potential prostate cancer. Ultrahigh b-value should not replace standard high b-values (1,500 s/mm²) for imaging workup of patients with suspicion for prostate cancer.

The aim was to evaluate visual breast lesion assessment using single binary index maps (IDf) in comparison to the use of combined regions of interest (ROI) analysis of estimated diffusion coefficient (D′) AND perfusion fraction (f′), which proved to be the best method in a previous simplified intravoxel incoherent motion DWI, if diffusion-weighted imaging (DWI) is used as stand-alone tool. IDf, was constructed voxel-wise from cut-off values of D′ and f′. The cut-off values, the data of 105 malignant and 86 benign lesions and the ROIs were re-used. For visual assessment, IDf was displayed as two-colour b800 overlay with red representing “malignant” and green “benign” voxels. A lesion was rated as “malignant”, if a red hot spot was found within translucent hyperintensity on b800, otherwise as “benign”. Intraindividual comparison of quantitative analysis and visual assessment of IDf showed comparable accuracy, both to each other and to combined ROI-analysis of D′ and f′ maps (0.927 vs. 0.937, p = 0.157, and 0.921 vs. 0.937, p = 0.157, respectively). Thus, visual assessment of IDf can replace combined ROI analysis of D′ and f′ without loss in accuracy enabling a considerable facilitation in clinical routine.

Aim was to evaluate accelerated diffusion-weighted imaging (DWI) of the prostate using echo planar imaging with compressed SENSE based reconstruction (EPICS) and assess its performance in comparison to conventional DWI with parallel imaging. In this single-center, prospective study, 35 men with clinically suspected prostate cancer underwent prostate MRI at 3T. In each patient, two different DWI sequences, one with 3 b-values (b = 100, 400, 800s/mm²) for ADC-calculation and one with b = 1500s/mm², were acquired with conventional SENSE and with EPICS. Quantitative evaluation was done by regions-of-interest (ROIs) analysis of prostate lesions and normal appearing peripheral zones (PZ). Apparent contrast-to-noise (aCNR) and apparent signal-to-noise ratios (aSNR) were calculated. Mean ADC and coefficient of variation (CV) of ADC were compared. For qualitative assessment, artifacts, lesion conspicuity, and overall image quality were rated using a 5-point-Likert-scale (1: nondiagnostic to 5: excellent). Additionally, the Prostate Imaging Reporting and Data System (PIRADS 2.1) was rated for DWI. The average total scan time reduction with EPICS was 43%. Quantitative analysis showed no significant differences between conventional SENSE and EPICS, neither for aSNRLesion (e.g. b1500conv: 24.37 ± 10.28 vs. b1500EPICS: 24.08 ± 12.2; p = 0.98) and aCNRLesion (e.g. b1500conv:9.53 ± 7.22 vs. b1500EPICS:8.88 ± 6.16; p = 0.55) nor for aSNRPZ (e.g. b1500conv:15.18 ± 6.48 vs. b1500EPICS: 15 ± 7.4; p = 0.94). Rating of artifacts, lesion conspicuity, overall image quality and PIRADS-scores yielded comparable results for the two techniques (e.g. lesion conspicuity for ADCconv: 4(2–5) vs. ADCEPICS 4(2–5); p = 0.99 and for b1500conv: 4(2–5) vs. b1500EPICS 4(2–5); p = 0.25). Overall, accelerated DWI of the prostate using EPICS significantly reduced acquisition time without compromising image quality compared to conventional DWI.

Abstract Objectives To implement and evaluate a super-fast and high-quality biparametric MRI (bpMRI) protocol for prostate imaging acquired at a new ultra-high gradient 3.0-T MRI system. Methods Participants with clinically suspected prostate cancer prospectively underwent a multiparametric MRI (mpMRI) on a new 3.0-T MRI scanner (maximum gradient strength: 200 mT/m, maximum slew rate: 200 T/m/s). The bpMRI protocol was extracted from the full mpMRI protocol, including axial T2-weighted and diffusion-weighted (DWI) sequences (b0/800, b1500). Overall image quality was rated by two readers on a five-point Likert scale from (1) non-diagnostic to (5) excellent. PI-RADS 2.1 scores were assessed by three readers separately for the bpMRI and mpMRI protocols. Cohen’s and Fleiss’ κ were calculated for PI-RADS agreement between protocols and interrater reliability between readers, respectively. Results Seventy-seven male participants (mean age, 66 ± 8 years) were included. Acquisition time of the bpMRI protocol was reduced by 62% (bpMRI: 5 min, 33 ± 21 s; mpMRI: 14 min, 50 ± 42 s). The bpMRI protocol showed excellent overall image quality for both the T2-weighted (median score both readers: 5 [IQR: 4–5]) and DWI (b1500) sequence (median score reader 1: 4 [IQR: 4–5]; reader 2: 4 [IQR: 4–4]). PI-RADS score agreement between protocols was excellent (Cohen’s κ range: 0.91–0.95 [95% CI: 0.89, 0.99]) with an overall good interrater reliability (Fleiss’ κ, 0.86 [95% CI: 0.80, 0.92]). Conclusion Ultra-high gradient MRI allows the establishment of a high-quality and rapidly acquired bpMRI with high PI-RADS agreement to a full mpMRI protocol. Trials registration Clinicaltrials.gov, NCT06244680, Registered 06 February 2024, retrospectively registered, https://classic.clinicaltrials.gov/ct2/show/NCT06244680. Critical relevance statement A novel 3.0-Tesla MRI system with an ultra-high gradient performance enabled high-quality biparametric prostate MRI in 5.5 min while achieving excellent PI-RADS agreement with a standard multiparametric protocol. Key Points Multi- and biparametric prostate MRIs were prospectively acquired utilizing a maximum gradient of 200 mT/m. Super-fast biparametric MRIs showed excellent image quality and had high PI-RADS agreement with multiparametric MRIs. Implementation of high gradient MRI in clinical routine allows accelerated and high-quality biparametric prostate examinations. Graphical Abstract

Background To evaluate simplified intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI) for differentiating malignant versus benign breast lesions as (i) stand-alone tool and (ii) add-on to dynamic contrast-enhanced magnetic resonance imaging. Methods 1.5-T DWI data ( b = 0, 50, 250, 800 s/mm 2 ) were retrospectively analysed for 126 patients with malignant or benign breast lesions. Apparent diffusion coefficient (ADC) ADC (0, 800) and IVIM-based parameters D 1 ′ = ADC (50, 800), D 2 ′ = ADC (250, 800), f 1 ′ = f (0, 50, 800), f 2 ′ = f (0, 250, 800) and D *′ = D * (0, 50, 250, 800) were voxel-wise calculated without fitting procedures. Regions of interest were analysed in vital tumour and perfusion hot spots. Beside the single parameters, the combined use of D 1 ′ with f 1 ′ and D 2 ′ with f 2 ′ was evaluated. Lesion differentiation was investigated for lesions (i) with hyperintensity on DWI with b = 800 s/mm 2 ( n = 191) and (ii) with suspicious contrast-enhancement ( n = 135). Results All lesions with suspicious contrast-enhancement appeared also hyperintense on DWI with b = 800 s/mm 2 . For task (i), best discrimination was reached for the combination of D 1 ′ and f 1 ′ using perfusion hot spot regions-of-interest (accuracy 93.7%), which was higher than that of ADC (86.9%, p = 0.003) and single IVIM parameters D 1 ′ (88.0%) and f 1 ′ (87.4%). For task (ii), best discrimination was reached for single parameter D 1 ′ using perfusion hot spot regions-of-interest (92.6%), which were slightly but not significantly better than that of ADC (91.1%) and D 2 ′ (88.1%). Adding f 1 ′ to D 1 ′ did not improve discrimination. Conclusions IVIM analysis yielded a higher accuracy than ADC. If stand-alone DWI is used, perfusion analysis is of special relevance.

Abstract The second part of this review deals with experiences in neuroradiological and pediatric examinations using modern magnetic resonance imaging systems with 1.5 T and 3 T, with special attention paid to experiences in pediatric cardiac imaging. In addition, whole-body examinations, which are widely used for diagnostic purposes in systemic diseases, are compared with respect to the image quality obtained in different body parts at both field strengths. A systematic overview of the technical differences at 1.5 T and 3 T has been presented in part 1 of this review, as well as several organ-based magnetic resonance imaging applications including musculoskeletal imaging, abdominal imaging, and prostate diagnostics.

To compare and combine the diagnostic performance of the apparent diffusion coefficient (ADC) derived from diffusion-weighted imaging (DWI) and proton density fat fraction (PDFF) derived from chemical-shift encoding (CSE)-based water-fat magnetic resonance imaging (MRI) for distinguishing benign and malignant vertebral bone marrow lesions (VBML). A total of 55 consecutive patients with 53 benign (traumatic, inflammatory and primary) and 36 malignant (metastatic and hematologic) previously untreated VBMLs were prospectively enrolled in this IRB-approved study and underwent sagittal DWI (single-shot spin-echo echo-planar with multi-slice short TI inversion recovery fat suppression) and CSE-based MRI (gradient-echo 6‑point modified Dixon) in addition to routine clinical spine MRI at 1.5 T or 3.0 T. Diagnostic reference standard was established according to histopathology or imaging follow-up. The ADC = ADC (0, 800) and PDFF = fat / (water + fat) were calculated voxel-wise and examined for differences between benign and malignant lesions. The ADC and PDFF values of malignant lesions were significantly lower compared to benign lesions (mean ADC 861 × 10−6 mm2/s vs. 1323 × 10−6 mm2/s, p < 0.001; mean PDFF 3.1% vs. 28.2%, p < 0.001). The areas under the curve (AUC) and diagnostic accuracies were 0.847 (p < 0.001) and 85.4% (cut-off at 1084.4 × 10−6 mm2/s) for ADC and 0.940 (p < 0.001) and 89.9% for PDFF (cut-off at 7.8%), respectively. The combined use of ADC and PDFF improved the diagnostic accuracy to 96.6% (malignancy if ADC ≤ 1118.2 × 10−6 mm2/s and PDFF ≤ 20.0%, otherwise benign). Quantitative evaluation of both ADC and PDFF was useful in differentiating benign VBMLs from malignancy. The combination of ADC and PDFF improved the diagnostic performance and yielded high diagnostic accuracy for the differentiation of benign and malignant VBMLs.

This study investigated the impact of different ROI placement and analysis methods on the diagnostic performance of simplified IVIM-DWI for differentiating liver lesions. 1.5/3.0-T DWI data from a respiratory-gated MRI sequence (b = 0, 50, 250, 800 s/mm 2 ) were analyzed in patients with malignant (n = 74/54) and benign (n = 35/19) lesions. Apparent diffusion coefficient ADC = ADC(0,800) and IVIM parameters D 1 ′ = ADC(50,800), D 2 ′ = ADC(250,800), f 1 ′ = f(0,50,800), f 2 ′ = f(0,250,800), and D*' = D*(0,50,250,800) were calculated voxel-wise. For each lesion, a representative 2D-ROI, a 3D-ROI whole lesion, and a 3D-ROI from “good” slices were placed, including and excluding centrally deviating areas (CDA) if present, and analyzed with various histogram metrics. The diagnostic performance of 2D- and 3D-ROIs was not significantly different; e.g. AUC (ADC/D 1 ′/f 1 ′) were 0.958/0.902/0.622 for 2D- and 0.942/0.892/0.712 for whole lesion 3D-ROIs excluding CDA at 1.5 T ( p > 0.05). For 2D- and 3D-ROIs, AUC (ADC/D 1 ′/D 2 ′) were significantly higher, when CDA were excluded. With CDA included, AUC (ADC/D 1 ′/D 2 ′/f 1 ′/D*') improved when low percentiles were used instead of averages, and was then comparable to the results of average ROI analysis excluding CDA. For lesion differentiation the use of a representative 2D-ROI is sufficient. CDA should be excluded from ROIs by hand or automatically using low percentiles of diffusion coefficients.

ABSTRACT Whole-body magnetic resonance imaging (MRI) systems with a field strength of 3 T have been offered by all leading manufacturers for approximately 2 decades and are increasingly used in clinical diagnostics despite higher costs. Technologically, MRI systems operating at 3 T have reached a high standard in recent years, as well as the 1.5-T devices that have been in use for a longer time. For modern MRI systems with 3 T, more complexity is required, especially for the magnet and the radiofrequency (RF) system (with multichannel transmission). Many clinical applications benefit greatly from the higher field strength due to the higher signal yield (eg, imaging of the brain or extremities), but there are also applications where the disadvantages of 3 T might outweigh the advantages (eg, lung imaging or examinations in the presence of implants). This review describes some technical features of modern 1.5-T and 3-T whole-body MRI systems, and reports on the experience of using both types of devices in different clinical settings, with all sections written by specialist radiologists in the respective fields.This first part of the review includes an overview of the general physicotechnical aspects of both field strengths and elaborates the special conditions of diffusion imaging. Many relevant aspects in the application areas of musculoskeletal imaging, abdominal imaging, and prostate diagnostics are discussed.

Abstract Background To evaluate the feasibility of two-colour index maps containing combined diffusion and perfusion information from simplified intravoxel incoherent motion (IVIM) for liver lesion malignancy assessment. Methods Diffusion-weighted data from a respiratory-gated 1.5-T magnetic resonance sequence were analysed in 109 patients with liver lesions. With three b values (0, 50, 800 s/mm2) estimated diffusion coefficient D′, perfusion fraction f′, and apparent diffusion coefficient (ADC) maps were calculated and analysed for regions of interest (ROIs). D′ and f′ cutoff values were determined by differentiating haemangiomas from other lesions and focal nodular hyperplasias from other lesions, respectively. Combined IDf index maps were generated with a voxel value set to 100, if both D′ and f′ voxel values were lower than their cutoff values (1,529.4 × 10-6 mm2/s and 114.4 × 10-3, respectively), otherwise to 0. Moreover, IADC index maps were generated from ADC cutoff value (1,338.5 × 10-6 mm2/s) obtained by differentiating benign from malignant lesions. Discriminatory power was assessed for both IDf and IADC. Index maps were displayed as two-colour overlays to b-800 images and visually assessed within the translucent hyperintense areas. Results For IDf, the same diagnostic accuracy was achieved as for the combined use of parameters D′ and f′ (93.6%). Compared to IADC, IDf showed a higher diagnostic accuracy. Visual judgment of IDf yielded an accuracy (95.4%) similar to that of quantitative analysis (93.6%). Conclusion Voxel-wise combined two-colour index maps IDf provide similar diagnostic accuracy as ROI-based combination of estimated IVIM parameters D′ and f′ and are suitable for visual assessment of liver lesion malignancy.

The original version of this article, published on 08 April 2019, unfortunately contained a mistake. The following correction has therefore been made in the original: The caption of Fig.2 is wrong. The corrected version is given below.

Neben malignen Läsionen können auch benigne Knochenmarksveränderungen ein malignomtypisches Signalverhalten in der MRT aufweisen und damit die Interpretation der Untersuchung erschweren. Von benignen Knochenmarksveränderungen ist bekannt, dass Sie im Vergleich zu malignen Läsionen höhere Mengen mikroskopischen Fettes und einen höheren scheinbaren Diffusionskoeffizienten (ADC) in der diffusionsgewichteten MRT (DWI) aufweisen. Ziel der Studie war es, die diagnostische Genauigkeit der Protonendichte-Fett-Fraktion (PDFF) und der DWI hinsichtlich ihrer diagnostischen Genauigkeit zur Differenzierung benigner und maligner Knochenmarksläsionen zu vergleichen.

The original version of this article, published on 08 April 2019, unfortunately contained a mistake. The following correction has therefore been made in the original: The caption of Fig. 2 is wrong. The corrected version is given below.

The objective of this study was to evaluate a simplified intravoxel incoherent motion (IVIM) approach of diffusion-weighted imaging (DWI) with four b-values for liver lesion characterisation at 1.5 T.

Objectives To evaluate measurement repeatability of parameters derived from simplified intravoxel incoherent motion (IVIM) analysis of diffusion-weighted imaging (DWI) using 3 b-values. Materials and Methods 24 patients (16 male, 8 female, mean age: 67 years) with hepatic malignancy (HCC: 10, metastases: 14) underwent 29 liver MRI examinations at 1.5 T. Respiratory-triggered DWI (b = 0, 50, 800 s/mm2) was acquired twice. Parameter maps of the apparent diffusion coefficient ADC(0,800), estimated diffusion coefficient D' and perfusion fraction f' were calculated. Measurement repeatability for a region of interest (ROI) placed in one lesion and liver parenchyma per lobe was assessed by intra-session variation coefficients (CV). Results 86 ROIs (43 lesions, 43 parenchymas) were analyzed. Parameters did not significantly differ between measurements. Repeatability was excellent for ADC(0,800) and D' and good for f' in parenchyma (CVs: 7.3 %, 9.8 %, 13.0 %) and lesions (CVs: 7.5 %, 8.5 %, 11.0 %). Differences in CV-values between liver and lesions were not significant. Repeatability was better for the right than for the left lobe by tendency, for parenchyma (CVs: 6.4 % vs 8.4 %, 8.8 % vs 10.9 %, 10.5 % vs 16.0 %) and for lesions (CVs: 6.9 % vs 8.1 %, 7.5 % vs 9.5 %, 9.5 % vs 12.7 %). Conclusion Measurement repeatability is excellent for ADC(0,800) and D' values and good for f' values using the simplified IVIM approach, both in lesions and liver parenchyma. Repeatability was better for lesions in the right compared to the left liver lobe. Key points: Citation Format

Purpose To directly compare different methods proposed for enhanced conspicuity and discriminability of prostate cancer on diffusion-weighted imaging (DWI) and to compare the results to original DWI images and conventional apparent diffusion coefficient (ADC) maps. Materials and Methods Clinical routine prostate DWI datasets (b = 0, 50, 800 s/mm(2), acquired at a field strength of 3 T) of 104 consecutive patients with subsequent MR-guided prostate biopsy were included in this retrospective study. For each dataset exponential ADC maps (eADC), computed DWI images (cDWI), and additionally eADC maps for computed b-values of 2000 and 3000 s/mm(2) were generated (c_eADC). For each of 123 lesions, the contrast (CR) and contrast-to-noise ratio (CNR) were determined. Differences in the CR and CNR of malignant lesions (n = 83) between the different image types and group differences between benign (n = 40), low-risk (n = 53) and high-risk (n = 30) lesions were assessed by repeated measures ANOVA and one-way ANOVA with post-hoc tests. The ability to differentiate between benign and malignant and between low-risk and high-risk lesions was assessed by receiver operating characteristic (ROC) curve analyses. Results The CR and CNR were higher for computed DWI and related c_eADC at b = 3000 s/mm(2) and 2000 s/mm(2) compared to original DWI, conventional ADC and standard eADC. For differentiation of benign and malignant lesions, conventional ADC and CR of conventional ADC were best suited. For discrimination of low-risk from high-risk lesions, the CR of c_eADC was best suited followed by the CR of cDWI. Conclusion Computed cDWI or related c_eADC maps at b-values between 2000 and 3000 s/mm2 were superior to the original DWI, conventional ADC and eADC in the detection of prostate cancer.

Objective: To evaluate diffusion-weighted whole-body MRI with background body signal suppression (DWIBS) at 3.0 T for pulmonary lesion detection and characterization. Materials and Methods: 19 patients with 25 pulmonary lesions were examined with DWIBS using 2 b-values (b = 0 and 1000 s/mm2) and partly additionally with DWIBS using 3 b-values (b = 0, 50, 1000 s/mm2). DWIBS was compared to FDG PET. For characterization of hyperintense lesions by DWIBS, Lesion-to-Spinal cord Ratio (LSR) and apparent diffusion coefficient ADC were analyzed. From repeated measurements, the Coefficient of Variation (CV) was calculated. From 3-b-value data, the ADC(0,1000) and ADC(50,1000) values were compared in order to assess perfusion influences. Results: Sensitivity and specificity of detecting malignant lesions were comparable for DWIBS and FDG PET. Malignant compared to benign lesions had lower ADC(0,1000) and higher LSR values. CV of LSR was more than a factor of 8 higher than CV of ADC(0,1000) (23.9% vs 2.9%, P = 0.012). Perfusion effects were largest for metastases, medium for adenocarcinoma and benign lesions, and lowest for squamous cell carcinoma. Conclusion: DWIBS at 3.0 T is appropriate for lesion detection and characterization. ADC analysis is superior to signal intensity ratio determination with respect to repeatability. An analysis of perfusion influences provides additional information.

Untersuchung von Änderungen der Intravoxel Incoherent Motion (IVIM) Parameter nach TIPS-Anlage bei Zirrhosepatienten.

To investigate differences in treatment-response characteristics of hepatocellular carcinoma (HCC) after resin- and glass-radioembolization by using intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI). 37 HCC-patients (mean age 68 years) underwent 44 primary radioembolizations (26 resin, 18 glass) with 1.5T liver-MRI including respiratory-gated DWI with b0 = 0, b1 = 50, b2 = 800s/mm2 before and four weeks after treatment. Apparent diffusion coefficient ADC (0,800), estimated diffusion coefficient D' and perfusion fraction f' were determined using a simplified IVIM-approach. One HCC-nodule was analyzed per radioembolization. Data were categorized into "response" (partial response/stable disease) and "non-response" (progressive disease) according to modified RECIST-criteria. 27 HCCs responded (16 resin, 11 glass); 17 did not respond (10 resin, 7 glass). Responders showed significantly larger pre-interventional f'-values than non-responders (p = 0.016) in resin-radioembolization. In contrast, responders to glass-radioembolization showed significantly smaller pre-interventional ADC (0,800)- and D'-values than non-responders (p = 0.0005 and p = 0.001, respectively). After therapy ADC (0,800)- and D'-values increased and f' decreased in responders (resin: p = 0.001, p<0.0001, p<0.0001, respectively; glass: p = 0.006, p = 0.001, p = 0.016, respectively). In non-responders, however, f' increased (p = 0.006) after resin-radioembolization, while ADC (0,800) and D' decreased (p = 0.023 and p = 0.032, respectively) after glass-radioembolization. Responders and non-responders were best differentiated by f'-changes (AUC of 1.0) in resin-radioembolization and D'-changes (AUC of 1.0) in glass-radioembolization. Response-prediction and early response-assessment after radioembolization of HCC is feasible using IVIM-analysis. Responding tumors show increasing diffusion-parameters (indicating necrosis) and decreasing perfusion-parameters (indicating necrosis and embolization) regardless of type of radioembolization. However, response to resin-embolization is indicated rather by perfusion-parameters (dominant embolization effect) and response to glass-radioembolization by diffusion-parameters.

Vergleich der Intravoxel Incoherent Motion (IVIM) Modell basierten Ansprechcharakteristika von hepatozellulären Karzinomen (HCC) nach Radioembolisation (RE) mit Harz- bzw. Glasmikrosphären.