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Feuerriegel GC, Marcus RP, Goller SS, Marth AA, Wieser K, Bouaicha S, Sutter R. A visual marker for early atrophy of the supraspinatus muscle on conventional MRI: introduction of the blackbird sign. Eur Radiol 2024:10.1007/s00330-024-10946-7. [PMID: 38992107 DOI: 10.1007/s00330-024-10946-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Revised: 05/10/2024] [Accepted: 06/15/2024] [Indexed: 07/13/2024]
Abstract
OBJECTIVES The aim of this study was to introduce the blackbird sign as a fast, qualitative measure of early supraspinatus (SSP) muscle atrophy and to correlate the sign with quantitatively assessed muscle volume and intramuscular fat fraction (FF) in patients with full-thickness SSP tears. MATERIALS AND METHODS The blackbird sign describes the asymmetric pattern of early SSP atrophy: on sagittal MR images, the supero-posterior contour of the muscle becomes concave, resembling the shape of a blackbird. MRIs of patients with full-thickness SSP tears were retrospectively reviewed for the presence of the blackbird and tangent signs. Patients were then divided into group 1: negative tangent sign and negative blackbird sign (n = 67), group 2: negative tangent sign and positive blackbird sign (n = 31), and group 3: positive tangent sign (n = 32). A 2-point Dixon sequence was acquired in all patients from which quantitative FF and muscle volumes were calculated. RESULTS In total 130 patients (mean age 67 ± 11 years) were included. Mean SSP volume was significantly smaller in group 3 (15.8 ± 8.1 cm3) compared to group 2 (23.9 ± 7.0 cm3, p = 0.01) and group 1 (29.7 ± 9.1 cm3, p < 0.01). Significantly lower muscle volumes were also found in group 2 compared to group 1 (p = 0.02), confirming that the blackbird sign is able to identify early SSP atrophy. Mean FF in the SSP was significantly higher in group 3 (18.5 ± 4.4%) compared to group 2 (10.9 ± 4.7%, p < 0.01) and group 1 (6.1 ± 2.6%, p < 0.01). CONCLUSION Visual assessment of early muscle atrophy of the SSP is feasible and reproducible using the blackbird sign, allowing the diagnosis of early SSP atrophy. CLINICAL RELEVANCE STATEMENT In routine clinical practice, the blackbird sign may be a useful tool for assessing early muscle degeneration before the risk of postoperative rotator cuff re-tears increases with progressive muscle atrophy and fatty infiltration. KEY POINTS Quantitative measurements of rotator cuff injuries require time, limiting clinical practicality. The proposed blackbird sign is able to identify early SSP atrophy. Reader agreement for the blackbird sign was substantial, demonstrating reproducibility and ease of implementation in the clinical routine.
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Affiliation(s)
- Georg C Feuerriegel
- Department of Radiology, Balgrist University Hospital, Faculty of Medicine, University of Zurich, Zurich, Switzerland.
| | - Roy P Marcus
- Department of Radiology, Balgrist University Hospital, Faculty of Medicine, University of Zurich, Zurich, Switzerland
| | - Sophia S Goller
- Department of Radiology, Balgrist University Hospital, Faculty of Medicine, University of Zurich, Zurich, Switzerland
| | - Adrian A Marth
- Department of Radiology, Balgrist University Hospital, Faculty of Medicine, University of Zurich, Zurich, Switzerland
- Swiss Center for Musculoskeletal Imaging, Balgrist Campus AG, Zurich, Switzerland
| | - Karl Wieser
- Department of Orthopedics, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Samy Bouaicha
- Department of Orthopedics, Balgrist University Hospital, University of Zurich, Zurich, Switzerland
| | - Reto Sutter
- Department of Radiology, Balgrist University Hospital, Faculty of Medicine, University of Zurich, Zurich, Switzerland
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Rau A, Jungmann PM, Diallo TD, Reisert M, Kellner E, Eisenblaetter M, Bamberg F, Jung M. Application of diffusion microstructure imaging in musculoskeletal radiology - translation from head to shoulders. Eur Radiol 2023; 33:1565-1574. [PMID: 36307552 PMCID: PMC9935724 DOI: 10.1007/s00330-022-09202-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 09/14/2022] [Accepted: 09/25/2022] [Indexed: 11/25/2022]
Abstract
OBJECTIVES Quantitative MRI techniques, such as diffusion microstructure imaging (DMI), are increasingly applied for advanced tissue characterization. We determined its value in rotator cuff (RC) muscle imaging by studying the association of DMI parameters to isometric strength and fat fraction (FF). METHODS Healthy individuals prospectively underwent 3T-MRI of the shoulder using DMI and chemical shift encoding-based water-fat imaging. RC muscles were segmented and quantitative MRI metrics (V-ISO, free fluid; V-intra, compartment inside of muscle fibers; V-extra, compartment outside of muscle fibers, and FF) were extracted. Isometric shoulder strength was quantified using specific clinical tests. Sex-related differences were assessed with Student's t. Association of DMI-metrics, FF, and strength was tested. A factorial two-way ANOVA was performed to compare the main effects of sex and external/internal strength-ratio and their interaction effects on quantitative imaging parameters ratios of infraspinatus/subscapularis. RESULTS Among 22 participants (mean age: 26.7 ± 3.1 years, 50% female, mean BMI: 22.6 ± 1.9 kg/m2), FF of the individual RC muscles did not correlate with strength or DMI parameters (all p > 0.05). Subjects with higher V-intra (r = 0.57 to 0.87, p < 0.01) and lower V-ISO (r = -0.6 to -0.88, p < 0.01) had higher internal and external rotation strength. Moreover, V-intra was higher and V-ISO was lower in all RC muscles in males compared to female subjects (all p < 0.01). There was a sex-independent association of external/internal strength-ratio with the ratio of V-extra of infraspinatus/subscapularis (p = 0.02). CONCLUSIONS Quantitative DMI parameters may provide incremental information about muscular function and microstructure in young athletes and may serve as a potential biomarker. KEY POINTS • Diffusion microstructure imaging was successfully applied to non-invasively assess the microstructure of rotator cuff muscles in healthy volunteers. • Sex-related differences in the microstructural composition of the rotator cuff were observed. • Muscular microstructural metrics correlated with rotator cuff strength and may serve as an imaging biomarker of muscular integrity and function.
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Affiliation(s)
- Alexander Rau
- Department of Diagnostic and Interventional Radiology, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Breisacher Str. 64, 79106, Freiburg, Germany.
- Department of Neuroradiology, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, 79106, Freiburg, Germany.
| | - Pia M Jungmann
- Department of Diagnostic and Interventional Radiology, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Breisacher Str. 64, 79106, Freiburg, Germany
| | - Thierno D Diallo
- Department of Diagnostic and Interventional Radiology, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Breisacher Str. 64, 79106, Freiburg, Germany
| | - Marco Reisert
- Medical Physics, Department of Diagnostic and Interventional Radiology, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, 79106, Freiburg, Germany
- Department of Stereotactic and Functional Neurosurgery, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, 79106, Freiburg, Germany
| | - Elias Kellner
- Medical Physics, Department of Diagnostic and Interventional Radiology, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, 79106, Freiburg, Germany
| | - Michel Eisenblaetter
- Department of Diagnostic and Interventional Radiology, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Breisacher Str. 64, 79106, Freiburg, Germany
| | - Fabian Bamberg
- Department of Diagnostic and Interventional Radiology, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Breisacher Str. 64, 79106, Freiburg, Germany
| | - Matthias Jung
- Department of Diagnostic and Interventional Radiology, Medical Center, University of Freiburg, Faculty of Medicine, University of Freiburg, Breisacher Str. 64, 79106, Freiburg, Germany
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Assessing breast density using the chemical-shift encoding-based proton density fat fraction in 3-T MRI. Eur Radiol 2022; 33:3810-3818. [PMID: 36538074 PMCID: PMC10182116 DOI: 10.1007/s00330-022-09341-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 11/22/2022] [Accepted: 11/29/2022] [Indexed: 12/24/2022]
Abstract
Abstract
Objectives
There is a clinical need for a non-ionizing, quantitative assessment of breast density, as one of the strongest independent risk factors for breast cancer. This study aims to establish proton density fat fraction (PDFF) as a quantitative biomarker for fat tissue concentration in breast MRI and correlate mean breast PDFF to mammography.
Methods
In this retrospective study, 193 women were routinely subjected to 3-T MRI using a six-echo chemical shift encoding-based water-fat sequence. Water-fat separation was based on a signal model accounting for a single T2* decay and a pre-calibrated 7-peak fat spectrum resulting in volumetric fat-only, water-only images, PDFF- and T2*-values. After semi-automated breast segmentation, PDFF and T2* values were determined for the entire breast and fibroglandular tissue. The mammographic and MRI-based breast density was classified by visual estimation using the American College of Radiology Breast Imaging Reporting and Data System categories (ACR A-D).
Results
The PDFF negatively correlated with mammographic and MRI breast density measurements (Spearman rho: −0.74, p < .001) and revealed a significant distinction between all four ACR categories. Mean T2* of the fibroglandular tissue correlated with increasing ACR categories (Spearman rho: 0.34, p < .001). The PDFF of the fibroglandular tissue showed a correlation with age (Pearson rho: 0.56, p = .03).
Conclusion
The proposed breast PDFF as an automated tissue fat concentration measurement is comparable with mammographic breast density estimations. Therefore, it is a promising approach to an accurate, user-independent, and non-ionizing breast density assessment that could be easily incorporated into clinical routine breast MRI exams.
Key Points
• The proposed PDFF strongly negatively correlates with visually determined mammographic and MRI-based breast density estimations and therefore allows for an accurate, non-ionizing, and user-independent breast density measurement.
• In combination with T2*, the PDFF can be used to track structural alterations in the composition of breast tissue for an individualized risk assessment for breast cancer.
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Wang TY, Nie P, Zhao X, Wang HX, Wan GY, Zhou RZ, Zhong X, Zhang Y, Yu TB, Hao DP. Proton density fat fraction measurements of rotator cuff muscles: Accuracy, repeatability, and reproducibility across readers and scanners. Magn Reson Imaging 2022; 92:260-267. [PMID: 35623416 DOI: 10.1016/j.mri.2022.05.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 05/19/2022] [Accepted: 05/19/2022] [Indexed: 10/18/2022]
Abstract
PURPOSE To determine the accuracy, repeatability, and reproducibility of magnetic resonance imaging-based proton density fat fraction (MRI-PDFF) measurements of rotator cuff muscles between two readers and three different scanners. METHODS Thirty-one volunteers underwent serial shoulder MRI examinations of both left and right sides on one 1.5-T MRI scanner and two 3.0-T MRI scanners. Two independent readers measured muscular PDFF of the supraspinatus, infraspinatus/teres minor muscle, and subscapularis. MR spectroscopy-based proton density fat fraction (MRS-PDFF) was regarded as the reference standard for assessing accuracy. A "coffee break" examination method was used to test the repeatability of each scanner. Bland-Altman plots, Pearson correlation, and linear regression analysis were used to assess bias and linearity. The Wilcoxon signed-rank test and Friedman test were applied to evaluate repeatability and reproducibility. RESULTS MRI-PDFF measurements indicated strong linearity (R2 = 0.749) and small bias (-0.18%) in comparison with the MRS-PDFF measurements. A very strong positive Pearson correlation (r = 0.955-0.986) between the PDFF estimates of the two repeat scans indicated excellent repeatability. The PDFF measurements showed high reproducibility, with a strong positive Pearson correlation (r = 0.668-0.698) and a small mean bias (-0.04 to -0.10%) across different scanners. CONCLUSION MRI-PDFF measurements of rotator cuff muscles were highly accurate, repeatable, and reproducible across different readers and scanners, leading us to the conclusion that PDFF can be a reliable and robust quantitative imaging biomarker for longitudinal or multi-center studies.
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Affiliation(s)
- Tong-Yu Wang
- Department of Radiology, The Affiliated Hospital of Qingdao University, Qingdao 266003, Shandong, China
| | - Pei Nie
- Department of Radiology, The Affiliated Hospital of Qingdao University, Qingdao 266003, Shandong, China
| | - Xia Zhao
- Department of Sports Medicine, The Affiliated Hospital of Qingdao University, Qingdao 266003, Shandong, China
| | - He-Xiang Wang
- Department of Radiology, The Affiliated Hospital of Qingdao University, Qingdao 266003, Shandong, China
| | - Guang-Yao Wan
- Department of Radiology, The Affiliated Hospital of Qingdao University, Qingdao 266003, Shandong, China
| | - Rui-Zhi Zhou
- Department of Radiology, The Affiliated Hospital of Qingdao University, Qingdao 266003, Shandong, China
| | - Xin Zhong
- Department of Radiology, The Affiliated Hospital of Qingdao University, Qingdao 266003, Shandong, China
| | - Yi Zhang
- Department of Sports Medicine, The Affiliated Hospital of Qingdao University, Qingdao 266003, Shandong, China
| | - Teng-Bo Yu
- Department of Sports Medicine, The Affiliated Hospital of Qingdao University, Qingdao 266003, Shandong, China.
| | - Da-Peng Hao
- Department of Radiology, The Affiliated Hospital of Qingdao University, Qingdao 266003, Shandong, China.
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Tan ET, Queler SC, Lin B, Endo Y, Burge AJ, Sternberg J, Potter HG, Sneag DB. Improved nerve conspicuity with water-weighting and denoising in two-point Dixon magnetic resonance neurography. Magn Reson Imaging 2021; 79:103-111. [PMID: 33753136 DOI: 10.1016/j.mri.2021.03.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 03/16/2021] [Accepted: 03/17/2021] [Indexed: 10/21/2022]
Abstract
BACKGROUND T2-weighted, two-point Dixon fast-spin-echo (FSE) is an effective technique for magnetic resonance neurography (MRN) that can provide quantitative assessment of muscle denervation. Low signal-to-noise ratio and inadequate fat suppression, however, can impede accurate interpretation. PURPOSE To quantify effects of principal component analysis (PCA) denoising on tissue signal intensities and fat fraction (FF) and to determine qualitative image quality improvements from both denoising and water-weighting (WW) algorithms to improve nerve conspicuity and fat suppression. STUDY TYPE Prospective. SUBJECTS Twenty-one subjects undergoing MR neurography evaluation (11/10 male/female, mean age = 46.3±13.7 years) with 60 image volumes. Twelve subjects (23 image volumes) were determined to have muscle denervation based on diffusely elevated T2 signal intensity. FIELD STRENGTH/SEQUENCE 3 T, 2D, two-point Dixon FSE. ASSESSMENT Qualitative assessment included overall image quality, nerve conspicuity, fat suppression, pulsation and ringing artifacts by 3 radiologists separately on a three-point scale (1 = poor, 2 = average, 3 = excellent). Quantitative measurements for FF and signal intensity relative to normal muscle were made for nerve, abnormal muscle and subcutaneous fat. STATISTICAL TESTS Linear and ordinal regression models were used for quantitative and qualitative comparisons, respectively; 95% confidence intervals (CIs) and p-values for pairwise comparisons were adjusted using the Holm-Bonferroni method. Inter-rater agreement was assessed using Gwet's agreement coefficient (AC2). RESULTS Simulations showed PCA-denoising reduced FF error from 2.0% to 1.0%, and from 7.6% to 3.1% at noise levels of 10% and 30%, respectively. In human subjects, PCA-denoising did not change signal levels and FF quantitatively. WW decreased fat signal significantly (-83.6%, p < 0.001). Nerve conspicuity was improved by WW (odds ratio, OR = 5.8, p < 0.001). Fat suppression was improved by both PCA (OR = 3.6, p < 0.001) and WW (OR = 2.2, p < 0.001). Overall image quality was improved by PCA + WW (OR = 1.7, p = 0.04). CONCLUSIONS WW and PCA-denoising improved nerve conspicuity and fat suppression in MR neurography. Denoising can potentially provide improved accuracy of FF maps for assessing fat-infiltrated muscle.
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Affiliation(s)
- Ek T Tan
- Department of Radiology and Imaging, Hospital for Special Surgery, New York, NY, USA.
| | - Sophie C Queler
- Department of Radiology and Imaging, Hospital for Special Surgery, New York, NY, USA
| | - Bin Lin
- Department of Radiology and Imaging, Hospital for Special Surgery, New York, NY, USA
| | - Yoshimi Endo
- Department of Radiology and Imaging, Hospital for Special Surgery, New York, NY, USA
| | - Alissa J Burge
- Department of Radiology and Imaging, Hospital for Special Surgery, New York, NY, USA
| | - Julia Sternberg
- Department of Radiology and Imaging, Hospital for Special Surgery, New York, NY, USA
| | - Hollis G Potter
- Department of Radiology and Imaging, Hospital for Special Surgery, New York, NY, USA
| | - Darryl B Sneag
- Department of Radiology and Imaging, Hospital for Special Surgery, New York, NY, USA
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Trudel G, Uhthoff HK, Wong K, Dupuis J, Laneuville O. Adipocyte hyperplasia: the primary mechanism of supraspinatus intramuscular fat accumulation after a complete rotator cuff tendon tear: a study in the rabbit. Adipocyte 2019; 8:144-153. [PMID: 31033395 PMCID: PMC6768259 DOI: 10.1080/21623945.2019.1609201] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Intramuscular fat (IMF) accumulates in muscles of the rotator cuff after tendon tear. The number and cross-sectional area of fat clumps and of adipocytes were quantified on osmium tetroxide stained sections of the proximal, middle and distal quarters of SSP muscles 4, 8 and 12 weeks after SSP tendon division in a rabbit model. Linear mixed-effects models were fitted to the data and statistical significance was evaluated by ANOVA. Both the number (P<0.001) and cross-sectional area (P<0.0005) of fat clumps increased after tendon detachment while time had no significant effect (both at P>0.01). IMF accumulation was more important in the distal quarter of detached SSP muscle near tendon sectioning and characterized by increases of the number (P<0.0005) and cross-sectional area of fat clumps (P<0.0005) compared to the proximal quarter. Adipocyte number increased after tendon detachment (P<0.0005) and over time (P<0.01). The cross-sectional area of adipocytes increased in the detached group compared to controls (P<0.01) while time had no significant effect (P>0.01). Interestingly, the number of adipocytes in the distal quarter increased (P<0.0005) but the cross-sectional area was smaller (P<0.0005) compared to adipocytes in the proximal quarter. Adipocyte hyperplasia localized near tendon sectioning was the main contributor to fat accumulation in the detached SSP muscles.
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Affiliation(s)
- Guy Trudel
- Bone and Joint Research Laboratory, Department of Medicine, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada
- Department of Medicine, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Hans K. Uhthoff
- Bone and Joint Research Laboratory, Department of Medicine, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada
- Department of Surgery, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Kayleigh Wong
- Bone and Joint Research Laboratory, Department of Medicine, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada
| | - Josée Dupuis
- Department of Biostatistics, Boston University School of Public Health, Boston, MA, USA
| | - Odette Laneuville
- Bone and Joint Research Laboratory, Department of Medicine, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
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Editorial Commentary: Do Patients With Femoroacetabular Impingement Syndrome Already Show Hip Muscle Atrophy? Arthroscopy 2019; 35:1454-1456. [PMID: 31054724 DOI: 10.1016/j.arthro.2019.02.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Accepted: 02/17/2019] [Indexed: 02/02/2023]
Abstract
Muscle atrophy, fatty degeneration, and strength deficits of the hip abductors, flexors, and even external rotators are well-known clinical and radiologic findings in patients with advanced hip osteoarthritis. More recently, in the context of prearthritic hip diseases, the role of hip muscle function in femoroacetabular impingement syndrome (FAIS) has gained greater focus for hip surgeons. Several studies have shown that patients with FAIS present with activation deficits of the hip muscles, which may result in hip muscle weakness. Nevertheless, previous studies have yet to determine whether young and mainly active patients with FAIS already show hip muscle atrophy. Future research is required to further characterize hip muscle function in patients with FAIS. Of particular interest is the investigation of whether both qualitative (muscle fatty degeneration) and quantitative (muscle atrophy) morphologic alterations of the hip muscles are present in patients with FAIS, as well as whether these alterations are sex specific and/or related to the underlying hip morphology.
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Jungmann PM, Gersing AS, Woertler K, Dietrich TJ, Baum T, Baumann F, Bensler S. Reliable semiquantitative whole‐joint MRI score for the shoulder joint: The shoulder osteoarthritis severity (SOAS) score. J Magn Reson Imaging 2018; 49:e152-e163. [DOI: 10.1002/jmri.26251] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Accepted: 06/22/2018] [Indexed: 11/06/2022] Open
Affiliation(s)
- Pia M. Jungmann
- Department of NeuroradiologyUniversity Hospital Zurich, University of Zurich Zurich Switzerland
- Department of RadiologyTechnical University of Munich Munich Germany
| | | | - Klaus Woertler
- Department of RadiologyTechnical University of Munich Munich Germany
| | - Tobias J. Dietrich
- Radiology and Nuclear MedicineKantonsspital St. Gallen St. Gallen Switzerland
| | - Thomas Baum
- Department of NeuroradiologyTechnical University of Munich Munich Germany
| | - Frederic Baumann
- Clinical and Interventional AngiologyUniversity Hospital Zurich, University of Zurich Zurich Switzerland
| | - Susanne Bensler
- Institute of RadiologyCantonal Hospital Baden Baden Switzerland
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