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Petersen A, Nagel SN, Hamm B, Elgeti T, Schaafs LA. The influence of left bundle branch block on myocardial T1 mapping. Sci Rep 2024; 14:5379. [PMID: 38438510 PMCID: PMC10912434 DOI: 10.1038/s41598-024-55821-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Accepted: 02/28/2024] [Indexed: 03/06/2024] Open
Abstract
Tissue characterisation using T1 mapping has become an established magnetic resonance imaging (MRI) technique to detect myocardial diseases. This retrospective study aimed to determine the influence of left bundle branch block (LBBB) on T1 mapping at 1.5 T. Datasets of 36 patients with LBBB and 27 healthy controls with T1 mapping (Modified Look-Locker inversion-recovery (MOLLI), 5(3)3 sampling) were included. T1 relaxation times were determined on mid-cavity short-axis images. R2 maps were generated as a pixel-wise indicator for the goodness of the fit of T1 maps. R2 values were significantly lower in patients with LBBB than in healthy controls (whole myocardium/septum, 0.997, IQR, 0.00 vs. 0.998, IQR, 0.00; p = 0.008/0.998, IQR, 0.00 vs. 0.999, IQR, 0.00; p = 0.027). Manual correction of semi-automated evaluation tended to improve R2 values but not significantly. Strain analysis was performed and the systolic dyssynchrony index (SDIglobal) was calculated as a measure for left ventricular dyssynchrony. While MRI is generally prone to artefacts, lower goodness of the fit in LBBB may be mainly attributable to asynchronous contraction. Therefore, careful checking of the source data and, if necessary, manual post-processing is important. New techniques might improve the goodness of the fit of T1 mapping by reducing sampling in the motion prone diastole of LBBB patients.
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Affiliation(s)
- Antonia Petersen
- Department of Radiology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Hindenburgdamm 30, 12203, Berlin, Germany.
| | - Sebastian Niko Nagel
- Academic Department of Diagnostic and Interventional Radiology and Paediatric Radiology, Protestant Hospital of the Bethel Foundation, Bielefeld University, Medical School and University Medical Center East Westphalia-Lippe, Burgsteig 13, 33617, Bielefeld, Germany
| | - Bernd Hamm
- Department of Radiology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Thomas Elgeti
- Department of Radiology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Lars-Arne Schaafs
- Department of Radiology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Hindenburgdamm 30, 12203, Berlin, Germany
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Weidlich M, Hamm B, Schaafs LA, Elgeti T. Epicardial fat volume and its association with cardiac arrhythmias in CT coronary angiography. Pol J Radiol 2024; 89:e122-e127. [PMID: 38510546 PMCID: PMC10953510 DOI: 10.5114/pjr.2024.135797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Accepted: 02/01/2024] [Indexed: 03/22/2024] Open
Abstract
Purpose This retrospective study aimed to investigate the epicardial fat volume in cardiac computed tomography (CT), its relationship with cardiac arrhythmias, and its correlation with the coronary artery disease reporting and data system (CAD-RADS) score. Material and methods Ninety-six patients who underwent CT coronary angiography (CTCA) were included in this study. Patient data, including demographic information, clinical history, and imaging data were collected retrospectively. Epicardial fat volume was quantified using a standardised algorithm, the CAD-RADS scoring system was applied to assess the extent of coronary artery disease (CAD). Descriptive statistics, correlation analyses, and receiver operating characteristics methods were used. Results The study found a significant correlation between epicardial fat volume and CAD-RADS score (r2 = 0.31; p < 0.001), indicating the known influence of epicardial fat on CAD risk. Moreover, patients with higher epicardial fat volumes were more likely to experience cardiac tachyarrhythmia (p < 0.001). Receiver operating characteristic analysis established a threshold value of 123 cm3 for epicardial fat volume to predict tachyarrhythmia with 80% sensitivity (AUC = 0.69). Conclusions In this study a volume of at least 123 cm3 epicardial fat in native coronary calcium scans is associated with cardiac tachyarrhythmia. In these patients, careful selection of suitable imaging protocols is advised.
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Affiliation(s)
- Matthias Weidlich
- Department of Radiology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Bernd Hamm
- Department of Radiology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Lars-Arne Schaafs
- Department of Radiology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Thomas Elgeti
- Department of Radiology, Charité-Universitätsmedizin Berlin, Berlin, Germany
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Alhazmi A, de Carvalho Fischer C, Schaafs LA, Seifarth C. [Epiploic appendagitis: an uncommon and nonsurgical cause of abdominal pain]. Chirurgie (Heidelb) 2023; 94:954-958. [PMID: 37698617 DOI: 10.1007/s00104-023-01960-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 07/29/2023] [Indexed: 09/13/2023]
Abstract
BACKGROUND Epiploic appendagitis (AE) is a rare cause of acute abdomen and is often misdiagnosed as other common causes of acute abdomen, such as acute appendicitis, cholecystitis or diverticulitis due to its low incidence and its nonspecific clinical picture. This study presents the clinical course of AE and typical radiological features for an early and correct diagnosis in order to emphasize the importance of an early and correct diagnosis of AE. METHODS This is a retrospective review of 43 patients diagnosed with AE between June 2010 and September 2022 at the Charité - University Hospital Berlin, Campus Benjamin Franklin. The medical records were reviewed regarding clinical und radiological features, anatomical location of the AE und treatment methods. RESULTS A total of 43 patients (29 male, 11 female) were diagnosed with AE and almost all patients presented with abdominal pain, except in 8 cases (18.6%). Specific findings in computer tomography (CT) with a typical picture of AE were found in 33 patients (76.7%). AE was mostly localized in the left colon: 12 were found in the sigmoid colon (27.9%), 16 in the descending colon (37.2%) and 5 at the junction of the descending colon and the sigmoid colon (11.6%). Of the patients 28 (65.1%) were admitted for conservative treatment and the rest of the patients were treated as outpatients. No patient underwent surgery, all were treated with analgesics (NSAID) and 17 patients received antibiotics in addition. CONCLUSION AE is a self-limiting disease and a common mimic of other serious causes of abdominal pain. Due to the emergence of the widespread use of imaging modalities, an early diagnosis of AE and a conservative approach as first choice of treatment in patients with AE could be established.
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Affiliation(s)
- Ahmad Alhazmi
- Klinik für Allgemein- und Viszeralchirurgie, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Hindenburgdamm 30, 12203, Berlin, Deutschland.
| | - Cynthia de Carvalho Fischer
- Klinik für Allgemein- und Viszeralchirurgie, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Hindenburgdamm 30, 12203, Berlin, Deutschland
| | - Lars-Arne Schaafs
- Klinik für Radiologie, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Hindenburgdamm 30, 12203, Berlin, Deutschland
| | - Claudia Seifarth
- Klinik für Allgemein- und Viszeralchirurgie, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Hindenburgdamm 30, 12203, Berlin, Deutschland
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Jensen LJ, Kim D, Elgeti T, Steffen IG, Schaafs LA, Hamm B, Nagel SN. The role of parametric feature maps to correct different volume of interest sizes: an in vivo liver MRI study. Eur Radiol Exp 2023; 7:48. [PMID: 37670193 PMCID: PMC10480134 DOI: 10.1186/s41747-023-00362-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Accepted: 06/13/2023] [Indexed: 09/07/2023] Open
Abstract
BACKGROUND Different volume of interest (VOI) sizes influence radiomic features. This study examined if translating images into feature maps before feature sampling could compensate for these effects in liver magnetic resonance imaging (MRI). METHODS T1- and T2-weighted sequences from three different scanners (two 3-T scanners, one 1.5-T scanner) of 66 patients with normal abdominal MRI were included retrospectively. Three differently sized VOIs (10, 20, and 30 mm in diameter) were drawn in the liver parenchyma (right lobe), excluding adjacent structures. Ninety-three features were extracted conventionally using PyRadiomics. All images were also converted to 93 parametric feature maps using a pretested software. Agreement between the three VOI sizes was assessed with overall concordance correlation coefficients (OCCCs), while OCCCs > 0.85 were rated reproducible. OCCCs were calculated twice: for the VOI sizes of 10, 20, and 30 mm and for those of 20 and 30 mm. RESULTS When extracted from original images, only 4 out of the 93 features were reproducible across all VOI sizes in T1- and T2-weighted images. When the smallest VOI was excluded, 5 features (T1-weighted) and 7 features (T2-weighted) were reproducible. Extraction from parametric maps increased the number of reproducible features to 9 (T1- and T2-weighted) across all VOIs. Excluding the 10-mm VOI, reproducibility improved to 16 (T1-weighted) and 55 features (T2-weighted). The stability of all other features also increased in feature maps. CONCLUSIONS Translating images into parametric maps before feature extraction improves reproducibility across different VOI sizes in normal liver MRI. RELEVANCE STATEMENT The size of the segmented VOI influences the feature quantity of radiomics, while software-based conversion of images into parametric feature maps before feature sampling improves reproducibility across different VOI sizes in MRI of normal liver tissue. KEY POINTS • Parametric feature maps can compensate for different VOI sizes. • The effect seems dependent on the VOI sizes and the MRI sequence. • Feature maps can visualize features throughout the entire image stack.
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Affiliation(s)
- Laura Jacqueline Jensen
- Charité-Universitätsmedizin Berlin, Department of Radiology, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Hindenburgdamm 30, 12203, Berlin, Germany.
| | - Damon Kim
- Charité-Universitätsmedizin Berlin, Department of Radiology, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Hindenburgdamm 30, 12203, Berlin, Germany.
| | - Thomas Elgeti
- Charité-Universitätsmedizin Berlin, Department of Radiology, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Ingo Günter Steffen
- Charité-Universitätsmedizin Berlin, Department of Radiology, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Lars-Arne Schaafs
- Charité-Universitätsmedizin Berlin, Department of Radiology, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Bernd Hamm
- Charité-Universitätsmedizin Berlin, Department of Radiology, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Sebastian Niko Nagel
- Charité-Universitätsmedizin Berlin, Department of Radiology, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Hindenburgdamm 30, 12203, Berlin, Germany
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Elgeti T, Fröhlich M, Wismayer KK, Tzschätzsch H, Hamm B, Sack I, Schaafs LA. The effect of smoking on quantification of aortic stiffness by ultrasound time-harmonic elastography. Sci Rep 2022; 12:17759. [PMID: 36273020 PMCID: PMC9588008 DOI: 10.1038/s41598-022-22638-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Accepted: 10/18/2022] [Indexed: 01/19/2023] Open
Abstract
Smoking is a significant cardiovascular risk factor that causes stiffening of the central arteries, especially the aorta. While vessel stiffness can be determined indirectly by measuring pulse wave velocity, elastography allows image-based determination of vessel stiffness while at the same time providing information on vascular morphology. This study compares abdominal aortic wall stiffness as measured by ultrasound time-harmonic elastography (THE) in fifteen smokers and fifteen age-matched non-smoking controls without a history of cardiovascular disease. Smokers had a significantly higher abdominal aortic wall stiffness with a mean shear wave speed of 2.66 m/s (95% confidence interval (CI) 2.59-2.72 m/s) compared to 2.40 m/s (95% CI 2.34-2.47 m/s) (p < 0.01) in the group of non-smokers. All other baseline characteristics including aortic diameter showed no significant differences. Inter-rater variability was excellent with an intraclass correlation coefficient of 0.99 (95% CI 0.98-0.99). Our results show that THE is sensitive to subclinical stiffening of the aorta in young and middle-aged smokers even before morphological changes occur and may therefore has the potential to serve as a screening tool for early aortic abnormalities and longitudinal risk factors for cardiovascular health.
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Affiliation(s)
- Thomas Elgeti
- grid.6363.00000 0001 2218 4662Charité – Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Radiology, Hindenburgdamm 30, 12203 Berlin, Germany
| | - Matthias Fröhlich
- grid.6363.00000 0001 2218 4662Charité – Universitätsmedizin Berlin, Charité – Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Neonatology, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Kim Kathrin Wismayer
- grid.6363.00000 0001 2218 4662Charité – Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Radiology, Hindenburgdamm 30, 12203 Berlin, Germany
| | - Heiko Tzschätzsch
- grid.6363.00000 0001 2218 4662Charité – Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Radiology, Hindenburgdamm 30, 12203 Berlin, Germany
| | - Bernd Hamm
- grid.6363.00000 0001 2218 4662Charité – Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Radiology, Hindenburgdamm 30, 12203 Berlin, Germany
| | - Ingolf Sack
- grid.6363.00000 0001 2218 4662Charité – Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Radiology, Hindenburgdamm 30, 12203 Berlin, Germany
| | - Lars-Arne Schaafs
- grid.6363.00000 0001 2218 4662Charité – Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Department of Radiology, Hindenburgdamm 30, 12203 Berlin, Germany
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Petersen A, Nagel SN, Hamm B, Elgeti T, Schaafs LA. Cardiac magnetic resonance imaging in patients with left bundle branch block: Patterns of dyssynchrony and implications for late gadolinium enhancement imaging. Front Cardiovasc Med 2022; 9:977414. [PMID: 36337885 PMCID: PMC9631472 DOI: 10.3389/fcvm.2022.977414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 09/30/2022] [Indexed: 11/16/2022] Open
Abstract
Background Left bundle branch block (LBBB) is a ventricular conduction delay with high prevalence. Aim of our study is to identify possible recurring patterns of artefacts in late gadolinium enhancement (LGE) imaging in patients with LBBB who undergo cardiac magnetic resonance imaging (MRI) and to define parameters of mechanical dyssynchrony associated with artefacts in LGE images. Materials and methods Fifty-five patients with LBBB and 62 controls were retrospectively included. Inversion time (TI) scout and LGE images were reviewed for artefacts. Dyssynchrony was identified using cardiac MRI by determining left ventricular systolic dyssynchrony indices (global, septal segments, and free wall segments) derived from strain analysis and features of mechanical dyssynchrony (apical rocking and septal flash). Results Thirty-seven patients (67%) with LBBB exhibited inhomogeneous myocardial nulling in TI scout images. Among them 25 (68%) patients also showed recurring artefact patterns in the septum or free wall on LGE images and artefacts also persisted in 18 (72%) of those cases when utilising phase sensitive inversion recovery. Only the systolic dyssynchrony index of septal segments allowed differentiation of patient subgroups (artefact/no artefact) and healthy controls (given as median, median ± interquartile range); LBBB with artefact: 10.44% (0.44–20.44%); LBBB without artefact: 6.82% (-2.18–15.83%); controls: 4.38% (1.38–7.38%); p < 0.05 with an area under the curve of 0.863 (81% sensitivity, 89% specificity). Septal flash and apical rocking were more frequent in the LBBB with artefact group than in the LBBB without artefact group (70 and 62% versus 33 and 17%; p < 0.05). Conclusion Patients with LBBB show recurring artefact patterns in LGE imaging. Use of strain analysis and evaluation of mechanical dyssynchrony may predict the occurrence of such artefacts already during the examination and counteract misinterpretation.
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Jensen LJ, Kim D, Elgeti T, Steffen IG, Schaafs LA, Hamm B, Nagel SN. Enhancing the stability of CT radiomics across different volume of interest sizes using parametric feature maps: a phantom study. Eur Radiol Exp 2022; 6:43. [PMID: 36104519 PMCID: PMC9474978 DOI: 10.1186/s41747-022-00297-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Accepted: 07/05/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In radiomics studies, differences in the volume of interest (VOI) are often inevitable and may confound the extracted features. We aimed to correct this confounding effect of VOI variability by applying parametric maps with a fixed voxel size. METHODS Ten scans of a cup filled with sodium chloride solution were scanned using a multislice computed tomography (CT) unit. Sphere-shaped VOIs with different diameters (4, 8, or 16 mm) were drawn centrally into the phantom. A total of 93 features were extracted conventionally from the original images using PyRadiomics. Using a self-designed and pretested software tool, parametric maps for the same 93 features with a fixed voxel size of 4 mm3 were created. To retrieve the feature values from the maps, VOIs were copied from the original images to preserve the position. Differences in feature quantities between the VOI sizes were tested with the Mann-Whitney U-test and agreement with overall concordance correlation coefficients (OCCC). RESULTS Fifty-five conventionally extracted features were significantly different between the VOI sizes, and none of the features showed excellent agreement in terms of OCCCs. When read from the parametric maps, only 8 features showed significant differences, and 3 features showed an excellent OCCC (≥ 0.85). The OCCCs for 89 features substantially increased using the parametric maps. CONCLUSIONS This phantom study shows that converting CT images into parametric maps resolves the confounding effect of VOI variability and increases feature reproducibility across VOI sizes.
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Affiliation(s)
- Laura J Jensen
- Klinik für Radiologie, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt- Universität zu Berlin, Hindenburgdamm 30, 12203, Berlin, Germany.
| | - Damon Kim
- Klinik für Radiologie, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt- Universität zu Berlin, Hindenburgdamm 30, 12203, Berlin, Germany.
| | - Thomas Elgeti
- Klinik für Radiologie, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt- Universität zu Berlin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Ingo G Steffen
- Klinik für Radiologie, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt- Universität zu Berlin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Lars-Arne Schaafs
- Klinik für Radiologie, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt- Universität zu Berlin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Bernd Hamm
- Klinik für Radiologie, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt- Universität zu Berlin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Sebastian N Nagel
- Klinik für Radiologie, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt- Universität zu Berlin, Hindenburgdamm 30, 12203, Berlin, Germany
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Elsholtz FHJ, Ro SR, Shnayien S, Dinkelborg P, Hamm B, Schaafs LA. Impact of double reading on NI-RADS diagnostic accuracy in reporting oral squamous cell carcinoma surveillance imaging - a single-center study. Dentomaxillofac Radiol 2022; 51:20210168. [PMID: 34233509 PMCID: PMC8693328 DOI: 10.1259/dmfr.20210168] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
OBJECTIVES The Neck Imaging Reporting and Data System (NI-RADS) is an increasingly utilized risk stratification tool for imaging surveillance after treatment for head and neck cancer. This study aims to measure the impact of supervision by subspecialized radiologists on diagnostic accuracy of NI-RADS when initial reading is performed by residents. METHODS 150 CT and MRI datasets were initially read by two trained residents, and then supervised by two subspecialized radiologists. Recurrence rates by NI-RADS category were calculated, and receiver operating characteristic (ROC) curves were plotted. After dichotomization of the NI-RADS system (category 1 vs categories 2 + 3+4 and categories 1 + 2 vs 3 + 4), sensitivity, specificity, positive and negative predictive value were calculated. RESULTS 26% of the reports were modified by the supervising radiologists. Area under the curve of ROC plots values of the supervision session were higher than those of the initial reading session for both the primary site (0.89 vs 0.86) and the neck (0.94 vs 0.91), but the difference was not statistically significant. For dichotomized NI-RADS category assignments, differences between the initial reading and the supervision session were statistically significant regarding specificity and PPV for the primary site (1 + 2 vs 3 + 4 and 1 vs 2 + 3+4) or even for both sites combined (1 vs 2 + 3+4). CONCLUSION NI-RADS enables trained resident radiologists to report surveillance imaging in patients with treated oral squamous cell carcinoma with high discriminatory power. Additional supervision by a subspecialized head and neck radiologist particularly improves specificity of radiological reports.
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Affiliation(s)
- Fabian Henry Jürgen Elsholtz
- Department of Radiology, Charité – Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Campus Benjamin Franklin, Berlin, Germany
| | - Sa-Ra Ro
- Department of Radiology, Charité – Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Campus Benjamin Franklin, Berlin, Germany
| | - Seyd Shnayien
- Department of Radiology, Charité – Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Campus Benjamin Franklin, Berlin, Germany
| | - Patrick Dinkelborg
- Department of Oral and Maxillofacial Surgery, Charité – Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Campus Benjamin Franklin, Berlin, Germany
| | - Bernd Hamm
- Department of Radiology, Charité – Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Campus Benjamin Franklin, Berlin, Germany
| | - Lars-Arne Schaafs
- Department of Radiology, Charité – Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Campus Benjamin Franklin, Berlin, Germany
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Elsholtz FHJ, Reiter R, Marticorena Garcia SR, Braun J, Sack I, Hamm B, Schaafs LA. Multifrequency magnetic resonance elastography-based tomoelastography of the parotid glands-feasibility and reference values. Dentomaxillofac Radiol 2022; 51:20210337. [PMID: 34558305 PMCID: PMC8693321 DOI: 10.1259/dmfr.20210337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
OBJECTIVES Accurate radiological differentiation of parotid tumors remains challenging despite recent technical advances in quantitative medical imaging. Multifrequency magnetic resonance elastography (MRE) could provide additional information on viscoelastic properties of normal and abnormal biological tissues. This study investigates the feasibility of MRE of the parotid glands in healthy participants and provides first reference values. METHODS 20 healthy participants underwent multifrequency MRE of both parotid glands at 3 Tesla. Shear waves at frequencies of 25, 30, 40, and 50 Hz were introduced into the participants' heads through the occiput using pressurized-air actuators. Shear wave speed (SWS) and loss angle of the shear modulus (φ) were reconstructed by tomoelastography post-processing as surrogate parameters for tissue stiffness and viscosity or fluidity. 10 participants underwent repeated MRE to determine test-retest reliability based on intraclass correlation coefficients. RESULTS All MRE datasets acquired could be included in the analysis. Mean SWS was 0.97 ± 0.13 m/s, and mean φ was 0.59 ± 0.05 rad, each for both sides combined and without notable lateral difference (p = 0.88/0.87). Test-retest reliability was good for SWS (ICC = 0.84 for both sides/ICC = 0.77 for the right side/ICC = 0.79 for the left side) and good to excellent for φ(ICC = 0.94/0.86/0.90). CONCLUSIONS Multifrequency MRE of the parotid glands is feasible and reliable. This technique, therefore, is a promising method for investigating the viscoelastic properties of salivary gland tumors in future studies.
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Affiliation(s)
- Fabian Henry Jürgen Elsholtz
- Department of Radiology, Charité – Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Campus Benjamin Franklin, Berlin, Germany
| | | | - Stephan Rodrigo Marticorena Garcia
- Department of Radiology, Charité – Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Campus Charité Mitte, Berlin, Germany
| | - Jürgen Braun
- Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Institute of Medical Informatics, Campus Charité Mitte, Berlin, Germany
| | - Ingolf Sack
- Department of Radiology, Charité – Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Campus Charité Mitte, Berlin, Germany
| | - Bernd Hamm
- Department of Radiology, Charité – Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Campus Benjamin Franklin, Berlin, Germany
| | - Lars-Arne Schaafs
- Department of Radiology, Charité – Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Campus Benjamin Franklin, Berlin, Germany
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Schaafs LA, Wyschkon S, Elgeti M, Nagel SN, Knebel F, Steffen IG, Makowski MR, Hamm B, Elgeti T. Diagnosis of Left Ventricular Diastolic Dysfunction Using Cardiac Magnetic Resonance Imaging: Comparison of Volume-Time Curves Derived from Long- and Short-Axis Cine Steady-State Free Precession Datasets. ROFO-FORTSCHR RONTG 2020; 192:764-775. [PMID: 32106325 DOI: 10.1055/a-1108-1892] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
PURPOSE To evaluate the diagnostic performance of diastolic function parameters derived from long-axis (LAX) planimetry compared with short-axis (SAX) volumetry in cardiac magnetic resonance imaging. MATERIALS AND METHODS Cine steady-state free precession (SSFP) datasets of 15 healthy participants (8 young and 7 middle aged) and 25 patients with echocardiographically proven diastolic dysfunction (9 mild, 9 moderate, and 7 severe) were retrospectively included. Volume-time curves for assessing left ventricular (LV) function were obtained by manually contouring the LV endocardial borders in SAX and LAX datasets. The time needed for contouring was recorded for each dataset. The following LV parameters were determined: end-diastolic volume (EDV), end-systolic volume (ESV), ejection fraction (EF), myocardial mass (MM), time to peak filling rate (TPFR), normalized peak filling rate (nPFR), and the ratio of early to late peak filling rate (E/A ratio). A Wilcoxon signed-rank test was used to compare subgroups based on age and severity of diastolic dysfunction for statistical differences. Intraclass correlation coefficients were used to assess intermethod and interobserver reliability. RESULTS Accuracy for the diagnosis of diastolic dysfunction was highest for E/A (mild diastolic dysfunction) and nPFR (any stage of diastolic dysfunction) derived from LAX datasets (E/A: area under the curve (AUC) = 0.97, sensitivity of 68 % and specificity of 100 %; nPFR: AUC = 0.84, sensitivity of 84 % and specificity of 80 %). Diastolic parameters showed a moderate to good intraclass correlation between both methods. The mean differences in EDV, ESV, EF, and MM were 5.3 ml, 1.9 ml, 3.5 %, and 11 g, respectively (each p < 0.001). Significantly less time was needed to derive volume-time curves from LAX images (median 14:45 min, interquartile range 14:15-15:53 min versus median 29:25 min, interquartile range 28:12-32:22 min; p = 0.001). The interobserver reliability was generally good to excellent. CONCLUSION Diastolic function parameters derived from left ventricular LAX planimetry have high diagnostic performance and can be obtained in significantly less time compared with SAX volumetry. These findings may pave the way for routine use of LAX planimetry in the clinical diagnosis of diastolic dysfunction. KEY POINTS · Diastolic function parameters derived from long-axis datasets have high diagnostic performance.. · Generation of volume-time curves using long-axis datasets requires significantly less time.. · This time savings may allow use of cardiac MRI for the diagnosis of diastolic dysfunction in the clinical routine.. CITATION FORMAT · Schaafs LA, Wyschkon S, Elgeti M et al. Diagnosis of Left Ventricular Diastolic Dysfunction Using Cardiac Magnetic Resonance Imaging: Comparison of Volume-Time Curves Derived from Long- and Short-Axis Cine Steady-State Free Precession Datasets. Fortschr Röntgenstr 2020; 192: 764 - 775.
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Affiliation(s)
- Lars-Arne Schaafs
- Department of Radiology, Charité-Universitätsmedizin Berlin, Germany
| | | | - Matthias Elgeti
- Jules-Eye-Stein-Institute, University of California Los Angeles, United States
| | | | - Fabian Knebel
- Department of Cardiology, Charité-Universitätsmedizin Berlin, Germany
| | - Ingo G Steffen
- Department of Radiology, Charité-Universitätsmedizin Berlin, Germany
| | - Marcus R Makowski
- Department of Radiology, Charité-Universitätsmedizin Berlin, Germany
| | - Bernd Hamm
- Department of Radiology, Charité-Universitätsmedizin Berlin, Germany
| | - Thomas Elgeti
- Department of Radiology, Charité-Universitätsmedizin Berlin, Germany.,Department of Nuclear Medicine, Charité-Universitätsmedizin Berlin, Germany
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Schaafs LA, Tzschätzsch H, Figiel C, van der Giet M, Reshetnik A, Hamm B, Sack I, Elgeti T. Quantitative Time-Harmonic Ultrasound Elastography of the Abdominal Aorta and Inferior Vena Cava. Ultrasound Med Biol 2019; 45:2349-2355. [PMID: 31201021 DOI: 10.1016/j.ultrasmedbio.2019.05.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 02/18/2019] [Accepted: 05/20/2019] [Indexed: 06/09/2023]
Abstract
The purpose of this study was to evaluate the sensitivity of quantitative time-harmonic ultrasound elastography (THE) of the inferior vena cava (IVC) and abdominal aorta (AA) to changes in central volume status. THE of the IVC and AA was performed in 20 healthy volunteers before and after oral intake of 1 L of water and before or during passive leg raising to augment venous filling. Compound maps of shear wave speed (SWS) as surrogate measures of vessel wall stiffness were generated within the full field of view from multifrequency harmonic wave fields. SWS was measured in regions of the IVC and AA. Blood pressure, stroke volume, cardiac output and pulse wave velocity were recorded. Statistical significance of SWS changes was tested using one-way repeated-measures analysis of variance. SWS measured in the IVC increased from 1.71 ± 0.1 m/s before water intake to 1.82 ± 0.1 m/s during passive leg raising and, further, to 1.87 ± 0.1 m/s after hydration and to 1.95 ± 0.1 m/s with hydration plus passive leg raising (p < 0.001). SWS in the AA did not change significantly after hydration (2.14 ± 0.13 m/s vs. 2.15 ± 0.16 m/s; p = 0.792). SWS was significantly higher in the AA than in the IVC across all experiments (p < 0.001). Water drinking did not significantly influence blood pressure, pulse wave velocity and cardiac output (all p values >0.1), whereas stroke volume increased significantly (p = 0.031). Time-harmonic ultrasound elastography enables quantification of the wall stiffness of the large abdominal vessels and is sensitive to different volume and pressure states in the IVC.
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Affiliation(s)
- Lars-Arne Schaafs
- Department of Radiology, Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin and Campus Mitte, Berlin, Germany.
| | - Heiko Tzschätzsch
- Department of Radiology, Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin and Campus Mitte, Berlin, Germany
| | - Christin Figiel
- Department of Radiology, Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin and Campus Mitte, Berlin, Germany
| | - Markus van der Giet
- Department of Nephrology, Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin, Berlin, Germany
| | - Alexander Reshetnik
- Department of Nephrology, Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin, Berlin, Germany
| | - Bernd Hamm
- Department of Radiology, Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin and Campus Mitte, Berlin, Germany
| | - Ingolf Sack
- Department of Radiology, Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin and Campus Mitte, Berlin, Germany
| | - Thomas Elgeti
- Department of Radiology, Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin and Campus Mitte, Berlin, Germany; Department of Nuclear Medicine, Charité-Universitätsmedizin Berlin, Campus Virchow Klinikum, Berlin, Germany
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Schaafs LA, Pfeil J, Köhlitz T, Hamm B, Niehues SM. LOW-DOSE COMPUTED TOMOGRAPHY OF THE PARANASAL SINUSES: PERFORMANCE OF TWO DIFFERENT ITERATIVE RECONSTRUCTION ALGORITHMS. Radiat Prot Dosimetry 2019; 183:386-392. [PMID: 30165539 DOI: 10.1093/rpd/ncy153] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 06/29/2018] [Accepted: 08/02/2018] [Indexed: 06/08/2023]
Abstract
To evaluate the performance of two iterative reconstruction algorithms in low-dose paranasal sinus computed tomography (CT). Sinus CT scans were reconstructed using Adaptive Iterative Dose Reduction 3D (AIDR 3D, n = 36 patients) or Sinogram Affirmed Iterative Reconstruction (SAFIRE, n = 32 patients). Reconstructed images were evaluated regarding subjective image quality, depiction of anatomic landmarks and noise (HU). Dose-length product (DLP), calculated effective dose (ED) and CT dose index (CTDIvol) were documented for each scan. Images were not significantly different in subjective image quality (p = 0.09) and conspicuity of anatomic landmarks (p = 0.28). Noise was significantly lower in images reconstructed with AIDR 3D (p = 0.012). DLP, ED and CTDIvol were significantly lower in the SAFIRE datasets (each p < 0.001). The results indicate that iterative reconstruction, independent of the manufacturer, enables for imaging the paranasal sinuses with an ED below 0.1 mSv while ensuring diagnostic image quality.
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Affiliation(s)
- Lars-Arne Schaafs
- Department of Radiology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Campus Benjamin Franklin, Hindenburgdamm 30, Berlin, Germany
| | - Julian Pfeil
- Department of Radiology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Campus Benjamin Franklin, Hindenburgdamm 30, Berlin, Germany
| | - Torsten Köhlitz
- Department of Radiology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Campus Benjamin Franklin, Hindenburgdamm 30, Berlin, Germany
| | - Bernd Hamm
- Department of Radiology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Campus Benjamin Franklin, Hindenburgdamm 30, Berlin, Germany
| | - Stefan Markus Niehues
- Department of Radiology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Campus Benjamin Franklin, Hindenburgdamm 30, Berlin, Germany
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Elsholtz FHJ, Schaafs LA, Erxleben C, Hamm B, Niehues SM. Periradicular infiltration of the lumbar spine: is iterative reconstruction software necessary to establish ultra-low-dose protocols? A quantitative and qualitative approach. Radiol Med 2018; 123:827-832. [PMID: 29923084 DOI: 10.1007/s11547-018-0913-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Accepted: 06/12/2018] [Indexed: 12/18/2022]
Abstract
PURPOSE Computed tomography (CT)-guided periradicular infiltration therapy has emerged as an effective treatment option for patients with low back pain. Concern about radiation exposure requires approaches allowing significant dose reduction. The purpose of this study is to evaluate the need for iterative reconstruction software in CT-guided periradicular infiltration therapy with an ultra-low-dose protocol. MATERIALS AND METHODS One hundred patients underwent CT-guided periradicular infiltration therapy of the lumbar spine using an ultra-low-dose protocol with adaptive iterative dose reduction 3D (AIDR 3D) for image reconstruction. In addition, images were reconstructed with filtered back-projection (FBP). Four experienced raters evaluated both reconstruction types for conspicuity of anatomical and instrumental features important for ensuring safe patient treatment. Image noise was measured as a quantitative marker of image quality. RESULTS Interrater agreement was good for both AIDR 3D (Kendall's W = 0.83) and FBP (0.78) reconstructions. Readers assigned the same scores for all features and both reconstruction algorithms in 81.3% of cases. Image noise was significantly lower (average SD of 60.07 vs. 99.54, p < 0.05) for AIDR 3D-reconstructed images. CONCLUSION Although it significantly lowers image noise, iterative reconstruction software is not mandatory to achieve adequate image quality with an ultra-low-dose CT protocol for guiding periradicular infiltration therapy of the lumbar spine.
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Affiliation(s)
- Fabian Henry Jürgen Elsholtz
- Klinik und Hochschulambulanz für Radiologie, Charité- Universitätsmedizin Berlin, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany.
| | - Lars-Arne Schaafs
- Klinik und Hochschulambulanz für Radiologie, Charité- Universitätsmedizin Berlin, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Christoph Erxleben
- Klinik und Hochschulambulanz für Radiologie, Charité- Universitätsmedizin Berlin, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Bernd Hamm
- Klinik und Hochschulambulanz für Radiologie, Charité- Universitätsmedizin Berlin, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Stefan Markus Niehues
- Klinik und Hochschulambulanz für Radiologie, Charité- Universitätsmedizin Berlin, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany
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Elsholtz FHJ, Schaafs LA, Köhlitz T, Hamm B, Niehues SM. Periradicular infiltration of the lumbar spine: testing the robustness of an interventional ultra-low-dose protocol at different body mass index levels. Acta Radiol 2017; 58:1364-1370. [PMID: 28273743 DOI: 10.1177/0284185117694508] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Background Computed tomography (CT)-guided periradicular infiltration remains a frequent interventional procedure for treatment of low back pain. Purpose To present an interventional ultra-low-dose protocol for CT-guided periradicular infiltration therapy and assess its application at different body mass index (BMI) levels. Material and Methods Over a period of 14 months, 79 patients underwent 183 CT-guided interventions for single-site lumbar periradicular therapy using an ultra-low-dose protocol with a basic setup of 100 kV and 5 mAs. Procedures were performed via intermittent fluoroscopy. A retrospective review was performed to analyze the parameters tube current and tube voltage, dose-length product, and BMI. Results The interventional ultra-low-dose protocol allowed safe treatment of 91.1% of the patients without a need for adapting the protocol. In seven patients with a higher BMI (range, 31-38 kg/m2; mean, 34 kg/m2), the tube current had to be increased to retain sufficient image quality. Only patients with a BMI of 30 and higher showed a significant correlation between BMI and dose-length product ( P value = 0.02), resulting in a slightly increased dose ( P value = 0.002). Conclusion The protocol presented for the interventional part of CT-guided periradicular infiltration allows to safely treat patients with a median calculated effective dose of 0.045 mSv (converted from a dose-length-product of 2.26 mGy*cm). Patients with a BMI of 30 and higher required a higher calculated effective dose with just one patient slightly exceeding 0.1 mSv.
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Affiliation(s)
| | | | | | - Bernd Hamm
- Charité-Universitätsmedizin Berlin, Berlin, Germany
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Schaafs LA, Tzschätzsch H, van der Giet M, Reshetnik A, Steffen IG, Hamm B, Braun J, Sack I, Elgeti T. Time-Harmonic Ultrasound elastography of the Descending Abdominal Aorta: Initial Results. Ultrasound Med Biol 2017; 43:2550-2557. [PMID: 28818306 DOI: 10.1016/j.ultrasmedbio.2017.07.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2017] [Revised: 06/28/2017] [Accepted: 07/07/2017] [Indexed: 06/07/2023]
Abstract
Stiffening of central large vessels is considered a key pathophysiologic factor within the cardiovascular system. Current diagnostic parameters such as pulse wave velocity (PWV) indirectly measure aortic stiffness, a hallmark of coronary diseases. The aim of the present study was to perform elastography of the proximal abdominal aorta based on externally induced time-harmonic shear waves. Experiments were performed in 30 healthy volunteers (25 young, 5 old, >50 y) and 5 patients with longstanding hypertension (PWV >10 m/s). B-Mode-guided sonographic time-harmonic elastography was used for measurement of externally induced shear waves at 30-Hz vibration frequency. Thirty-hertz shear wave amplitudes (SWAs) within the abdominal aorta were measured and displayed in real time and processed offline for differences in SWA between systole and diastole (ΔSWA). Data were analyzed using the Kruskal-Wallis test and receiver operating characteristic curve analysis. The change in SWA over the cardiac cycle was reduced significantly in all patients as assessed with ΔSWA (volunteers: mean = 10 ± 5 μm, patients: mean = 4 ± 1 μm; p < 0.001). The best separation of healthy volunteers from patients was obtained with a ΔSWA threshold of 4.7 μm, resulting in a sensitivity of 0.9 and a specificity of 1.0, with an overall area under the curve of 0.96. Time harmonic elastography of the abdominal aorta is feasible and shows promise for the exploitation of time-varying shear wave amplitudes as a diagnostic marker for aortic wall stiffening. Patients with elevated PWVs suggesting increased aortic wall stiffness were best identified by ΔSWA-a parameter that could be related to the ability of the vessel walls to distend on passages of the pulse wave.
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Affiliation(s)
- Lars-Arne Schaafs
- Klinik und Hochschulambulanz für Radiologie, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Heiko Tzschätzsch
- Klinik und Hochschulambulanz für Radiologie, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Markus van der Giet
- Medizinische Klinik mit Schwerpunkt Nephrologie, Transplantationszentrum-Hypertoniezentrum, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Alexander Reshetnik
- Medizinische Klinik mit Schwerpunkt Nephrologie, Transplantationszentrum-Hypertoniezentrum, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Ingo G Steffen
- Klinik und Hochschulambulanz für Radiologie, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Bernd Hamm
- Klinik und Hochschulambulanz für Radiologie, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Jürgen Braun
- Institut für Medizinische Informatik, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Ingolf Sack
- Klinik und Hochschulambulanz für Radiologie, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Thomas Elgeti
- Klinik und Hochschulambulanz für Radiologie, Charité-Universitätsmedizin Berlin, Berlin, Germany.
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Schaafs LA, Grozdanovic Z. A 76-Year-Old Woman With Chest Pain and Tarry Stool. Dtsch Arztebl Int 2017; 114:544. [PMID: 28835331 PMCID: PMC5624278 DOI: 10.3238/arztebl.2017.0544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Affiliation(s)
- Lars-Arne Schaafs
- *Klinik und Hochschulambulanz für Radiologie, Campus Benjamin Franklin, Charité-Universitätsmedizin Berlin,
| | - Zarko Grozdanovic
- *Klinik und Hochschulambulanz für Radiologie, Campus Benjamin Franklin, Charité-Universitätsmedizin Berlin,
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Schaafs LA, Lenk J, Hamm B, Niehues SM. Reducing the dose of CT of the paranasal sinuses: potential of an iterative reconstruction algorithm. Dentomaxillofac Radiol 2016; 45:20160127. [PMID: 27351346 DOI: 10.1259/dmfr.20160127] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE To evaluate the feasibility and image quality of low-dose CT of the paranasal sinuses using iterative reconstruction with adaptive-iterative dose reduction in three dimensions (AIDR 3D) in comparison with conventional image protocols of older scanner generations. METHODS Sinus CT scans of 136 patients were assessed retrospectively. Patients underwent CT either with low-dose settings (Protocol A: 80 kV, 30 mA s; Protocol B: 120 kV, 15 mA s or C: 80 kV, 90 mA s) reconstructed using AIDR 3D (Protocols A and B) or filtered back projection (FBP) (Protocol C) or with standard dose (Protocol D: 120 kV, 80 mA s) and FBP. Image quality was assessed in consensus by two blinded readers scoring the diagnostic image quality (from 1 = excellent to 5 = non-diagnostic) and conspicuity of important anatomic landmarks (from 0 = not visible to 2 = completely visible; maximum score of 16 points) as well as osseous structures (maximum score of 12 points). Dose-length product, effective dose (ED), CT dose index and scan length were retrieved for each scan and compared. RESULTS Mean ED could be lowered by 82% when using Protocol A. The best image quality was found using Protocol B (mean score = 2.1 ± 0.51). Conspicuity of relevant anatomic landmarks was best with Protocol A (mean score = 11.97 ± 1.88). Protocol B provided the highest conspicuity of osseous structures (mean score = 8.27 ± 1.58). Image noise was highest in images obtained using Protocol A. CONCLUSIONS AIDR 3D allows a significant dose reduction while maintaining a good diagnostic image quality and conspicuity of relevant anatomic structures.
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Affiliation(s)
- Lars-Arne Schaafs
- Department of Radiology, Campus Benjamin Franklin, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Julian Lenk
- Department of Radiology, Campus Benjamin Franklin, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Bernd Hamm
- Department of Radiology, Campus Benjamin Franklin, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Stefan Markus Niehues
- Department of Radiology, Campus Benjamin Franklin, Charité-Universitätsmedizin Berlin, Berlin, Germany
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Preuß A, Schaafs LA, Werncke T, Steffen IG, Hamm B, Elgeti T. Run-Off Computed Tomography Angiography (CTA) for Discriminating the Underlying Causes of Intermittent Claudication. PLoS One 2016; 11:e0152780. [PMID: 27054846 PMCID: PMC4824428 DOI: 10.1371/journal.pone.0152780] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Accepted: 03/19/2016] [Indexed: 12/21/2022] Open
Abstract
Aim To evaluate run-off computed tomography angiography (CTA) of abdominal aorta and lower extremities for detecting musculoskeletal pathologies and clinically relevant extravascular incidental findings in patients with intermittent claudication (IC) and suspected peripheral arterial disease (PAD). Does run-off CTA allow image-based therapeutic decision making by discriminating the causes of intermittent claudication in patients with suspected peripheral arterial disease PAD? Material and Methods Retrospective re-evaluation of CTAs performed in patients with acute or chronic intermittent claudication (i.e., Fontaine stages I to IIB) between January 2005 and October 2013. Allocation to one of three categories of underlying causes of IC symptoms: vascular, musculoskeletal (MSK) or both. Clinically relevant extravascular incidental findings were evaluated. Medical records were reviewed to verify specific therapies as well as main and incidental findings. Results While focused on vascular imaging, CTA image quality was sufficient for evaluation of the MSK system in all cases. The underlying cause of IC was diagnosed in run-off CTA as vascular, MSK and a combination in n = 138 (65%), n = 10 (4%), and n = 66 (31%) cases, respectively. Specific vascular or MSK therapy was recorded in n = 123 and n = 9 cases. In n = 82, no follow-up was possible. Clinically relevant extravascular incidental findings were detected in n = 65 patients (30%) with neoplasia, ascites and pleural effusion being the most common findings. Discussion Run-off CTA allows identification of vascular, MSK, and combined causes of IC in patients with suspected PAD and can guide specific therapy. CTA also allowed confident detection of crEVIF although detection did not necessarily trigger workup or treatment.
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Affiliation(s)
- Alexandra Preuß
- Department of Radiology, Charité-Universitätsmedizin, Berlin, Germany
| | - Lars-Arne Schaafs
- Department of Radiology, Charité-Universitätsmedizin, Berlin, Germany
- * E-mail:
| | - Thomas Werncke
- Institute for Radiology, Medizinische Hochschule Hannover, Hannover, Germany
| | - Ingo G. Steffen
- Department of Radiology, Charité-Universitätsmedizin, Berlin, Germany
| | - Bernd Hamm
- Department of Radiology, Charité-Universitätsmedizin, Berlin, Germany
| | - Thomas Elgeti
- Department of Radiology, Charité-Universitätsmedizin, Berlin, Germany
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Schaafs LA, Porter D, Audebert HJ, Fiebach JB, Villringer K. Optimising MR perfusion imaging: comparison of different software-based approaches in acute ischaemic stroke. Eur Radiol 2016; 26:4204-4212. [PMID: 26852218 DOI: 10.1007/s00330-016-4244-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Revised: 01/05/2016] [Accepted: 01/22/2016] [Indexed: 11/29/2022]
Abstract
OBJECTIVES Perfusion imaging (PI) is susceptible to confounding factors such as motion artefacts as well as delay and dispersion (D/D). We evaluate the influence of different post-processing algorithms on hypoperfusion assessment in PI analysis software packages to improve the clinical accuracy of stroke PI. METHODS Fifty patients with acute ischaemic stroke underwent MRI imaging in the first 24 h after onset. Diverging approaches to motion and D/D correction were applied. The calculated MTT and CBF perfusion maps were assessed by volumetry of lesions and tested for agreement with a standard approach and with the final lesion volume (FLV) on day 6 in patients with persisting vessel occlusion. RESULTS MTT map lesion volumes were significantly smaller throughout the software packages with correction of motion and D/D when compared to the commonly used approach with no correction (p = 0.001-0.022). Volumes on CBF maps did not differ significantly (p = 0.207-0.925). All packages with advanced post-processing algorithms showed a high level of agreement with FLV (ICC = 0.704-0.879). CONCLUSIONS Correction of D/D had a significant influence on estimated lesion volumes and leads to significantly smaller lesion volumes on MTT maps. This may improve patient selection. KEY POINTS • Assessment on hypoperfusion using advanced post-processing with correction for motion and D/D. • CBF appears to be more robust regarding differences in post-processing. • Tissue at risk is estimated more accurately by correcting software algorithms. • Advanced post-processing algorithms show a higher agreement with the final lesion volume.
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Affiliation(s)
- Lars-Arne Schaafs
- Department of Radiology, Charité-Universitätsmedizin, Hindenburgdamm 30, 12203, Berlin, Germany. .,Academic Neuroradiology, Department of Neurology and Center for Stroke Research, Charité-Universitätsmedizin, Berlin, Germany.
| | - David Porter
- Fraunhofer Institute for Medical Image Computing MEVIS, Bremen, Germany
| | - Heinrich J Audebert
- Department of Neurology with Experimental Neurology, Charité-Universitätsmedizin, Berlin, Germany
| | - Jochen B Fiebach
- Academic Neuroradiology, Department of Neurology and Center for Stroke Research, Charité-Universitätsmedizin, Berlin, Germany
| | - Kersten Villringer
- Academic Neuroradiology, Department of Neurology and Center for Stroke Research, Charité-Universitätsmedizin, Berlin, Germany
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Villringer K, Grittner U, Schaafs LA, Nolte CH, Audebert H, Fiebach JB. IV t-PA influences infarct volume in minor stroke: a pilot study. PLoS One 2014; 9:e110477. [PMID: 25350762 PMCID: PMC4211677 DOI: 10.1371/journal.pone.0110477] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Accepted: 09/13/2014] [Indexed: 11/18/2022] Open
Abstract
Background There is an ongoing debate whether stroke patients presenting with minor or moderate symptoms benefit from thrombolysis. Up until now, stroke severity on admission is typically measured with the NIHSS, and subsequently used for treatment decision. Hypothesis Acute MRI lesion volume assessment can aid in therapy decision for iv-tPA in minor stroke. Methods We analysed 164 patients with NIHSS 0–7 from a prospective stroke MRI registry, the 1000+ study (clinicaltrials.org NCT00715533). Patients were examined in a 3 T MRI scanner and either received (n = 62) or did not receive thrombolysis (n = 102). DWI (diffusion weighted imaging) and PI (perfusion imaging) at admission were evaluated for diffusion - perfusion mismatch. Our primary outcome parameter was final lesion volume, defined by lesion volume on day 6 FLAIR images. Results The association between t-PA and FLAIR lesion volume on day 6 was significantly different for patients with smaller DWI volume compared to patients with larger DWI volume (interaction between DWI and t-PA: p = 0.021). Baseline DWI lesion volume was dichotomized at the median (0.7 ml): final lesion volume at day 6 was larger in patients with large baseline DWI volumes without t-PA treatment (median difference 3, IQR −0.4–9.3 ml). Conversely, in patients with larger baseline DWI volumes final lesion volumes were smaller after t-PA treatment (median difference 0, IQR −4.1–5 ml). However, this did not translate into a significant difference in the mRS at day 90 (p = 0.577). Conclusion Though this study is only hypothesis generating considering the number of cases, we believe that the size of DWI lesion volume may support therapy decision in patients with minor stroke. Trial Registration Clinicaltrials.org NCT00715533
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Affiliation(s)
- Kersten Villringer
- Academic Neuroradiology, Department of Neurology and Center for Stroke Research, Charité, Berlin, Germany
- * E-mail:
| | - Ulrike Grittner
- Department for Biostatistics and Clinical Epidemiology and Center for Stroke Research, Charité, Berlin, Germany
| | - Lars-Arne Schaafs
- Academic Neuroradiology, Department of Neurology and Center for Stroke Research, Charité, Berlin, Germany
| | - Christian H. Nolte
- Department of Neurology and Center for Stroke Research, Charité, Berlin, Germany
| | - Heinrich Audebert
- Department of Neurology and Center for Stroke Research, Charité, Berlin, Germany
| | - Jochen B. Fiebach
- Academic Neuroradiology, Department of Neurology and Center for Stroke Research, Charité, Berlin, Germany
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Niehues S, Schaafs LA, Hamm B. Potential der iteraktiven Rekonstruktion bei CT-Datensätzen der Nasennebenhöhlen. ROFO-FORTSCHR RONTG 2014. [DOI: 10.1055/s-0034-1373147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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