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Purpose: To investigate whether potential differences in staging between a traditional staging imaging algorithm and 18 F-FDG PET/MR lead to a change in patient management in breast carcinoma and to compare the diagnostic accuracy between the traditional staging algorithm and 18 F-FDG PET/MR for the TNM classification., Method: In this prospective cohort study from two university hospitals 56 women with newly diagnosed, therapy-naive breast cancer and increased pre-test probability for distant metastases were included. All patients were examined by a traditional staging imaging algorithm (X-ray mammography, breast ultrasonography, chest plain radiography, bone scintigraphy, and ultrasonography of the liver and axillary fossa) and whole-body 18 F-FDG PET/MR including dedicated 18 F-FDG PET/MR breast examinations. Each patient was discussed two times in a separate tumor board session to determine a total of three therapy recommendations based on histopathological data of the primary tumor and (1) traditional algorithm only, (2) traditional algorithm and 18 F-FDG PET/MR, and (3) 18 F-FDG PET/MR only. Major changes in therapy recommendations and differences between the traditional staging algorithm and 18 F-FDG PET/MR for the TNM classification were evaluated., Results: Staging by 18 F-FDG PET/MR led to a difference in treatment compared the traditional staging algorithm in 8/56 cases (14%). Therapy changes included therapy of the breast, locoregional nodes and systemic therapy. A trend to staging superiority was found for 18 F-FDG PET/MRI without statistical significance (p = 0.3827)., Conclusion: In conclusion, for breast cancer patients with elevated pre-test probability for distant metastases a change of the therapy regiment occurs in 14 % of patients when staged by 18 F-FDG PET/MR and confirmed by histopathology compared to a traditional staging algorithm. In particular with regard to the amendment of the guideline further assessment of 18 F-FDG-PET/MR in this setting is necessary to assess the true value of this modality., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Objectives: To investigate the diagnostic value of different MR sequences and 18F-FDG PET data for whole-body restaging of breast cancer patients utilizing PET/MRI., Methods: A total of 36 patients with suspected tumor recurrence of breast cancer based on clinical follow-up or abnormal findings in follow-up examinations (e.g. CT, MRI) were prospectively enrolled in this study. All patients underwent a PET/CT and subsequently an additional PET/MR scan. Two readers were instructed to identify the occurrence of a tumor relapse in subsequent MR and PET/MR readings, utilizing different MR sequence constellations for each session. The diagnostic confidence for the determination of a malignant or benign lesion was qualitatively rated (3-point ordinal scale) for each lesion in the different reading sessions and the lesion conspicuity (4-point ordinal scale) for the three different MR sequences was additionally evaluated., Results: Tumor recurrence was present in 25/36 (69%) patients. All three PET/MRI readings showed a significantly higher accuracy as well as higher confidence levels for the detection of recurrent breast cancer lesions when compared to MRI alone (p<0.05). Furthermore, all three PET/MR sequence constellations showed comparable diagnostic accuracy for the identification of a breast cancer recurrence (p>0.05), yet the highest confidence levels were obtained, when all three MR sequences were used for image interpretation. Moreover, contrast-enhanced T1-weighted VIBE imaging showed significantly higher values for the delineation of malignant and benign lesions when compared to T2w HASTE and diffusion-weighted imaging., Conclusion: Integrated PET/MRI provides superior restaging of breast cancer patients over MRI alone. Facing the need for appropriate and efficient whole-body PET/MR protocols, our results show the feasibility of fast and morphologically adequate PET/MR protocols. However, considering an equivalent accuracy for the detection of breast cancer recurrences in the three PET/MR readings, the application of contrast-agent and the inclusion of DWI in the study protocol seems to be debatable., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Purpose: To investigate imaging findings in patients with primary breast sarcoma (PBS)., Materials and Methods: A retrospective search in the databases of 10 radiological departments in Germany from 2000 to 2011 was performed. Only histologically proven cases of PBS were included into the study. Mammography was available in 31 patients (33 lesions), ultrasound images in 24 patients (24 lesions), and for 10 patients (14 lesions) magnetic resonance imaging (MRI) of the breast was performed. The breast findings were classified according to the American College of Radiology Breast Imaging Reporting and Data Systems (BI-RADS) 5th edition categories. Collected data were evaluated by means of descriptive statistics., Results: Forty-two female patients (mean age 62.0 years, range, 30-86 years) were included in the study. Clinically, all women had painless lumps. Irregular (53.3% [16/30]) or oval (30.0% [9/30]) mass with indistinct (73.3% [22/30]) or microlobulated (10% [3/30]) margins were common findings on mammograms. Ultrasound revealed typically an irregular (79.2% [19/24]), hypoechoic (62.5% [15/24]) mass, with indistinct margins (79.2% [19/24]), and posterior acoustic shadowing (79.2% [19/24]). MRI showed irregular masses (81.8% [9/11]) with irregular or spiculated margins, and a rapid initial signal increase with a delayed washout in kinetic analysis., Conclusion: Overall, PBS has no pathognomonic imaging features and can mimic those of invasive mammary carcinoma. Breast sarcoma should be taken into the differential diagnosis of breast findings described above., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Objectives: To compare the diagnostic performance of (18)F-fluordesoxyglucose positron emission tomography/magnetic resonance imaging ((18)F-FDG PET/MRI) with (18)F-FDG PET/computed tomography ((18)F-FDG PET/CT), MRI, and CT in whole-body staging of recurrent breast cancer., Material and Methods: Twenty-one consecutive patients (age 59.4 ± 11.5 years, range 38.5-76.9 years; 20 female, 1 male) with suspected breast cancer recurrence underwent a clinically indicated (18)F-FDG PET/CT and subsequently a (18)F-FDG PET/MRI examination in a single injection protocol (mean injected activity: 257 ± 44 MBq (18)F-FDG). Each (18)F-FDG PET/MRI, (18)F-FDG PET/CT, as well as the CT component of PET/CT (CTPET/CT) and MR images of PET/MRI (MRIPET/MRI) were separately evaluated by two radiologists regarding lesion count, lesion localization, and lesion categorization (benign/malignant). The reference standard was based on histopathological results as well as prior and follow-up imaging. A Wilcoxon test assessed differences in SUVmax between (18)F-FDG PET/MRI and (18)F-FDG PET/CT. Correlation of SUVmax between (18)F-FDG PET/MRI and (18)F-FDG PET/CT was calculated using Pearson's correlation coefficient. Interobserver agreement on dignity ratings was evaluated using Cohen's kappa., Results: According to the reference standard, 17 patients had breast cancer recurrence. (18)F-FDG PET/MRI, (18)F-FDG PET/CT, and MRIPET/MRI correctly identified each of the 17 patients, whereas CTPET/CT correctly identified 15 of the 17 patients. A total of 134 lesions were described (116 malignant, 18 benign). (18)F-FDG PET/MRI detected all 134 lesions, of which (18)F-FDG PET/CT, MRIPET/MRI, and CTPET/CT detected 97.0%, 96.2%, and 74.6%, respectively. (18)F-FDG PET/MRI yielded the highest proportion of correctly categorized lesions (98.5%) compared with (18)F-FDG PET/CT (94.8%), MRIPET/MRI (88.1%), and CTPET/CT (57.5%). SUVmax was strongly correlated (r=0.72) but measured significantly higher on (18)F-FDG PET/MRI than on (18)F-FDG PET/CT in corresponding PET-positive lesions (SUVmax: 5.6 ± 2.8 vs. 4.9 ± 1.8; p=0.001). Interobserver agreement on lesion dignity was substantial with (18)F-FDG PET/MRI (k=0.65; p<0.001) and (18)F-FDG PET/CT (k=0.65; p<0.001). With MRIPET/MRI interobserver analysis yielded a moderate agreement (k=0.56; p<0.001), whereas there was only fair agreement evaluating the CTPET/CT datasets (k=0.31; p=0.002)., Conclusions: (18)F-FDG PET/MRI offered the highest diagnostic performance compared with (18)F-FDG PET/CT, MRI and CT. Thus, (18)F-FDG PET/MRI should be regarded as a valuable alternative in whole-body staging of recurrent breast cancer., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

Purpose: To implement a protocol for PET/MR enterography for a multimodal assessment of intestinal pathologies., Materials and Methods: 19 patients with bowel malignancies, Crohn's disease or fever of unknown origin (male: n=14, female: n=5, age: 57±13years) underwent PET/MR enterography with either [(18)F]FDG (n=10) or [(68)Ga]-DOTATOC (n=9) using an integrated scanner. For small bowel distension a contrast solution (1500 cm(3) of mannitol and locust bean gum) was ingested. The following sequences were acquired: (a) coronal TrueFISP; (b) coronal T2w HASTE; (c) coronal dynamic T1w VIBE; (d) axial and coronal T1w FLASH post gadolinium. All datasets were reviewed by two readers with regard to co-registration of anatomical structures based on a 3-point ordinal scale as well as overall image quality using a 4-point ordinal scale. Furthermore, visualization of intestinal and extra-intestinal pathologies was assessed., Results: PET/MR enterography was well tolerated by all patients. High overall MR image quality was achieved (mean score: 3.2±0.6) with good co-registration of PET and MRI (mean scores: 2.6 to 3.0). PET/MR enterography allowed for an excellent visualization of both intestinal as well as extra-intestinal pathologies., Conclusion: PET/MR enterography is technically feasible and offers good co-registration of bowel structures. This novel method enables a multimodal assessment of bowel lesions in malignant and inflammatory disease., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

Objectives: To compare the diagnostic competence of FAST-PET/MRI and PET/CT for whole-body staging of female patients suspect for a recurrence of a pelvic malignancy., Methods: 24 female patients with a suspected tumor recurrence underwent a PET/CT and subsequent PET/MRI examination. For PET/MRI readings a whole-body FAST-protocol was implemented. Two readers separately evaluated the PET/CT and FAST PET/MRI datasets regarding identification of all tumor lesions and qualitative assessment of visual lesion-to-background contrast (4-point ordinal scale)., Results: Tumor relapse was present in 21 of the 24 patients. Both, PET/CT and PET/MRI allowed for correct identification of tumor recurrence in 20 of 21 cases. Lesion-based sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy for the detection of malignant lesions were 82%, 91%, 97%, 58% and 84% for PET/CT and 85%, 87%, 96%, 63% and 86% for PET/MRI, lacking significant differences. Furthermore, no significant difference for lesion-to-background contrast of malignant and benign lesions was found., Conclusion: FAST-PET/MRI provides a comparably high diagnostic performance for restaging gynecological cancer patients compared to PET/CT with slightly prolonged scan duration, yet enabling a markedly reduced radiation exposure., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

Introduction: Detailed knowledge of the biliary anatomy is essential to avoid complications in living donor liver transplantation. The aim of this study was to determine the optimal dosage of Gd-EOB-DTPA for contrast-enhanced magnetic resonance cholangiography (ce-MRC) with reference to contrast-enhanced CT cholangiography (ce-CTC)., Materials and Methods: 30 potential living liver donors (PLLD) underwent both ce-CTC and ce-MRC. Ten candidates each received single, double or half-dose Gd-EOB-DTPA. Ce-MRC images with and without inversion recovery pulses (T1w±IR) were acquired 20-30min after intravenous contrast injection. Image data was quantitatively and qualitatively reviewed by two radiologists based on a on a 5-point scale. Data sets were compared using a Mann-Whitney-U-test or Wilcoxon-rank-sum-test. Kappa values were also calculated., Results: All image series provided sufficient diagnostic information both showing normal biliary anatomy and variant bile ducts. Ce-CTC showed statistically significant better results compared to all ce-MRC data sets. T1w MRC with single dose Gd-EOB-DTPA proved to be superior to half and double dose in subjective and objective evaluation without a statistically significant difference., Conclusions: Ce-MRC is at any dosage inferior to ce-CTC. As far as preoperative planning of bile duct surgery is focused on the central biliary anatomy, ce-MRC can replace harmful ce-CTC strategies, anyway. Best results were seen with single dose GD-EOB-DTPA on T1w MRC+IR., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Objectives: Preoperative magnetic resonance (MR) guided wire localization is a frequently used tool to target MR-only visible breast lesions. Different techniques are available. Targeting can be performed using automated software or a manual approach. Aim of this study therefore was to compare manually and automated software assisted wire localization of suspicious breast lesions regarding to image time and accurate positioning., Methods: 60 females with suspicious breast lesions underwent MR-guided wire localization. In 30 patients a manual target calculation and in another 30 patients a software calculated approach was used. Time measurements for MR imaging as well as calculation of the target coordinates were performed. Furthermore size measurements of (i) lesions, (ii) distance to wire anchor as well as, (iii) distance to skin were performed. A Mann-Whitney-test was used for statistical evaluation., Results: Total imaging time was shorter for the automated software calculated approach but failed to show a statistical significant difference (p=0.13). Time for localization of the lesions was significantly shorter for the software based method (p<0.001). Lesion sizes, distances to wire anchor and skin showed no statistically significant differences., Conclusions: Preoperative MR-guided wire localization of suspicious lesions that are accessible horizontally, a manually or automated software generated target calculation can be used. As MR guided wire localization of breast lesions needs its time in total, a minimal time consuming approach and therefore an automated software calculated targeting (if available) should be preferred., (Copyright © 2013. Published by Elsevier Ireland Ltd.)

The aim of this study was to investigate the feasibility of dynamic contrast-enhanced 7 T MRI of the liver using an eight-channel radiofrequency (RF) transmit/receive body-coil. 16 healthy subjects were examined on a 7 T MR system utilizing a custom-built eight-channel RF body-coil suitable for RF-shimming. The following data were acquired: (1) steady state free precession imaging, (2) T2w turbo spin echo imaging, (3) T1w in and opposed-phase imaging, (4) T1w 3D FLASH images pre-contrast and in arterial, portal-venous and venous phase and (5) a fat-saturated pre- and post-contrast 2D FLASH sequence. Visual evaluation of (1) the delineation of liver vasculature, (2) the overall image quality, and (3) artifact presence and consequent image impairment was performed. SNR of the liver parenchyma was measured for the contrast-enhanced 2D and 3D FLASH sequences. For statistical analysis, a Wilcoxon-Rank Test was used. Best delineation of non-enhanced liver vasculature and overall image quality was found for 2D FLASH MRI, with only slight improvement in vessel conspicuity after the application of contrast media. T2-weighted TSE imaging remained strongly impaired, falling short of diagnostic relevance and precluding a clinical application. Our results demonstrate the feasibility and diagnostic potential of dedicated contrast-enhanced 7 T liver MRI as well as the potential for non-contrast-enhanced angiographic application., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Purpose: Diffusion weighted imaging (DWI) is an emerging technique for abdominal MR and usually performed before intravenous contrast injection. Recent studies performed in patients with normal liver function have shown that DWI can be performed after gadolinium administration. Aim of this study was to compare DWI before and after administration of different gadolinium compounds in patients with HCC and liver cirrhosis., Materials and Methods: 15 patients with known HCC and liver cirrhosis underwent liver MRI at 1.5T (Magnetom Avanto, Siemens) including DWI on day 1 before and after administration of gadobutrol (Gadovist(®)) and on day 2 after administration of EOB-Gadolinium-DTPA (Primovist(®)). Signal to noise ratios (SNR) and contrast to noise ratios (CNR) of HCC lesions were determined for all DWI data sets. Furthermore, ADC values were compared using a Wilcoxon test. A p-value <0.05 indicated statistically significant differences., Results: There were no statistically significant differences regarding SNR pre-contrast (mean: 48.1), after gadobutrol (mean: 47.7) or after EOB-Gadolinium-DTPA (mean: 50.0; values for b=50s/mm(2)). Similarly, no significant differences were found for CNR (average values:34.4 vs. 32.3 vs. 30.7; b=50s/mm(2)) nor for ADC-values (mean: 1.5 vs. 1.4 vs. 1.5×10(-3)mm(2)/s) of HCC., Conclusion: There is no significant difference regarding DWI in patients with cirrhosis before and after contrast injection. Hence, it is reliable to run DWI after gadolinium either as an alternative for unsuccessful pre-contrast DWI or as a gap filler to spare time in EOB-Gadolinium-DTPA imaging., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

Purpose: Two different forms of biliary anastomosis can be created in patients undergoing liver transplantation: (a) bilio-digestive anastomoses or (b) choledocho-choledochostomy. Aim of this study was to assess the accuracy of MR cholangiopancreatography (MRCP) for the depiction of biliary stenoses in liver transplant patients depending on the type of biliary anastomosis., Method and Materials: 24 liver transplant patients with clinical suspicion of biliary stenosis were studied (each 12 with bilio-digestive anastomosis/choledocho-choledochostomy). MRCP was performed on a 1.5 T scanner (Magnetom Avanto, Siemens) including 2D single shot RARE, 2D T2w HASTE, TrueFISP and 3D high-resolution navigator corrected sequences. Presence of (a) anastomotic stenoses (AST) and (b) NAS (non-anastomotic strictures) were assessed. Percutaneous transhepatic cholangiography (PTC) or endoscopic retrograde cholangiopancreatography (ERCP) were performed within 48h after MRCP and served as the standard of reference., Results: In patients with bilio-digestive anastomoses sensitivities of MRCP for the detection of AST and NAS amounted to 50% and 67%, respectively with specificity values of 83% and 50%. In patients with choledocho-chledochostomy sensitivities (AST: 100%, NAS: 100%) and specificities (AST: 100%, NAS: 88%) were significantly higher., Conclusion: Biliary strictures after liver transplantation can be accurately detected by MRCP in patients after choledocho-chledochostomy. However, the diagnostic value of MRCP is lower if liver transplantation was performed in combination with a bilio-digestive anastomosis. This may be due to the less exact depiction of the anastomosis in the bowel wall. Thus, it is crucial to know the type of biliary anastomosis before choosing a diagnostic procedure., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)