A5075630875- Radiation Dose and Imaging
- Advanced X-ray and CT Imaging
- Medical Imaging Techniques and Applications
- Cardiac Imaging and Diagnostics
- Radiology practices and education
- Ultrasound in Clinical Applications
- Venous Thromboembolism Diagnosis and Management
- Advanced MRI Techniques and Applications
- Cardiovascular Function and Risk Factors
- MRI in cancer diagnosis
- Gallbladder and Bile Duct Disorders
- Pancreatic and Hepatic Oncology Research
- Pediatric Hepatobiliary Diseases and Treatments
- Dental Radiography and Imaging
- Congenital Heart Disease Studies
- Gastrointestinal disorders and treatments
- Cholangiocarcinoma and Gallbladder Cancer Studies
- Hepatocellular Carcinoma Treatment and Prognosis
- Digital Radiography and Breast Imaging
- Adrenal and Paraganglionic Tumors
- Vascular Procedures and Complications
- Autopsy Techniques and Outcomes
- Radiomics and Machine Learning in Medical Imaging
- Biliary and Gastrointestinal Fistulas
- Aortic aneurysm repair treatments
Kantonsspital Aarau
2017-2024
University Hospital of Basel
2012-2024
University of Bern
2005-2022
University Hospital of Zurich
2020
University of Basel
2012-2019
Swiss Society of Radiology
2018
Klinik und Poliklinik für Nuklearmedizin
2016
Siemens Healthcare (Germany)
2016
University Hospital of Bern
2005-2014
University Health Network
2013-2014
To investigate whether an adaptive statistical iterative reconstruction (ASIR) algorithm improves the image quality at low-tube-voltage (80-kVp), high-tube-current (675-mA) multidetector abdominal computed tomography (CT) during late hepatic arterial phase.This prospective, single-center HIPAA-compliant study was institutional review board approved. Informed patient consent obtained. Ten patients (six men, four women; mean age, 63 years; age range, 51-77 years) known or suspected to have...
Dual-energy CT provides information about how substances behave at different energies, the ability to generate virtual unenhanced datasets, and improved detection of iodine-containing on low-energy images. Knowing a substance behaves two energies can provide tissue composition beyond that obtainable with single-energy techniques. The term K edge refers spike in attenuation occurs energy levels just greater than K-shell binding because increased photoelectric absorption these levels. K-edge...
Abstract Objective To determine patient, institution, and machine characteristics that contribute to variation in radiation doses used for computed tomography (CT). Design Prospective cohort study. Setting Data were assembled analyzed from the University of California San Francisco CT International Dose Registry. Participants Standardized data over 2.0 million examinations adults who underwent between November 2015 August 2017 151 institutions, across seven countries (Switzerland,...
To intraindividually compare a low tube voltage (80 kVp), high current computed tomographic (CT) technique with standard CT protocol (140 kVp) in terms of image quality, radiation dose, and detection malignant hypervascular liver tumors during the late hepatic arterial phase.This prospective single-center HIPAA-compliant study had institutional review board approval, written informed consent was obtained. Forty-eight patients (31 men, 17 women; age range, 35-77 years) 60 (mean diameter, 20.1...
Purpose: To prospectively evaluate, for the depiction of simulated hypervascular liver lesions in a phantom, effect low tube voltage, high current computed tomographic (CT) technique on image noise, contrast-to-noise ratio (CNR), lesion conspicuity, and radiation dose. Materials Methods: A custom phantom containing 16 cylindric cavities (four each 3, 5, 8, 15 mm diameter) filled with various iodinated solutions to simulate was scanned 64-section multi–detector row CT scanner at 140, 120,...
To compare the low-contrast detectability and image quality of computed tomography (CT) at different radiation dose levels reconstructed with iterative reconstruction (IR) filtered back projection (FBP).A custom liver phantom 12 simulated hypoattenuating tumors (diameters 5, 10, 15, 20 mm; tumor-to-liver contrast values -10, -20, -40 HU) was designed. The scanned a standard abdominal CT protocol volume index 21.6 mGy (equivalent 100% dose) four low-dose protocols (20%, 40%, 60%, 80% dose)....
To intraindividually compare a low-tube-voltage (80 kVp), high-tube-current (675 mA) computed tomographic (CT) technique with high-tube-voltage (140 kVp) CT protocol for the detection of pancreatic tumors, image quality, and radiation dose during parenchymal phase.This prospective, single-center, HIPAA-compliant study was approved by institutional review board, written informed consent obtained. Twenty-seven patients (nine men, 18 women; mean age, 64 years) 23 solitary tumors underwent...
Purpose To assess the diagnostic accuracy, image quality, and radiation dose of an iterative reconstruction algorithm compared with a filtered back projection (FBP) for abdominal computed tomography (CT) at different tube voltages. Materials Methods A custom liver phantom 45 simulated hypovascular tumors (diameters 5, 10, 15 mm; tumor-to-liver contrast 25, 50 HU) was placed in cylindrical water container that mimicked intermediate-sized patient. The scanned 120, 100, 80 kVp. CT data sets...
The aim of this study was to investigate the image quality, radiation dose, and accuracy virtual noncontrast images iodine quantification split-filter dual-energy computed tomography (CT) using a single x-ray source in phantom patient study.In study, objective quality were evaluated for mode tin gold filter. In dose compared thoracoabdominal CT 50 patients between standard single-energy mode. estimated by size-specific estimate. To evaluate imaging, attenuation measurements liver, spleen,...
Objective: Measures to reduce radiation exposure and injected iodine mass are becoming more important with the widespread often repetitive use of pulmonary CT angiography (CTA) in patients suspected embolism. In this retrospective study, we analyzed capability 2 low-kilovoltage CTA-protocols achieve these goals. Materials Methods: Ninety weighing less than 100 kg were examined by a CTA protocol using either kVp (group A) or 80 B). Volume flow rate contrast medium reduced group B (75 mL at 3...
To compare image quality and radiation dose of thoracoabdominal computed tomography (CT) angiography at 80 100 kVp to assess the feasibility reducing contrast medium volume from 60 45 mL kVp.This retrospective study had institutional review board approval; informed consent was waived. Seventy-five patients who undergone 64-section multidetector-row CT were divided into 3 groups 25 each. Patients A (tube voltage, kVp) B received 4 mL/s. group C Mean aortoiliac attenuation, noise,...
The purpose of this study was to evaluate in a phantom the effect patient size on radiation dose for abdominal MDCT with automatic tube current modulation.One or two 4-cm-thick circumferential layers fat-equivalent material were added abdomen an anthropomorphic simulate patients three sizes: small (cross-sectional dimensions, 18 x 22 cm), average (26 30 and oversize (34 38 cm). Imaging performed 64-MDCT scanner combined z-axis xy-axis modulation according protocols: protocol A had noise...
Rising concerns of radiation exposure from computed tomography have caused various advances in dose reduction technologies. While proper justification and optimization scans has been the main focus to address increasing doses, value management largely overlooked. The purpose this article is explain importance management, provide an overview available options for tracking, discuss a dedicated team. authors also describe how digital tracking software can be used analyzing big data on doses...
To prospectively determine quantitatively and qualitatively the timing of maximal enhancement normal small-bowel wall by using contrast material-enhanced multi-detector row computed tomography (CT).This HIPAA-compliant study was approved institutional review board. After information on radiation risk given, written informed consent obtained from 25 participants with no history disease (mean age, 58 years; 19 men) who had undergone single-level dynamic CT. Thirty seconds after intravenous...
The detection rate of pulmonary emboli (PE) with computed tomography angiography (CTA) using either a standard or low-dose protocol, combining reduced radiation exposure and iodine delivery rate, was retrospectively analyzed in matched cohort 120 patients.The study performed according to the regulations institutional review board. Four groups 30 patients each, body weight less than 100 kg receiving CTA were by age (range, 21-87 years), gender (female/male, 48/72), 41-99 kg), cross sectional...
Abstract The European Directive 2013/59/Euratom requires member states of the Union to ensure justification and optimisation radiological procedures store information on patient exposure for analysis quality assurance. EuroSafe Imaging campaign Society Radiology created a working group (WG) “Dose Management” with aim provide recommendations implementation dose management systems (DMS) in clinical practice. WG follows Action 4: “Promote establish local, national, diagnostic reference levels...
The European Society of Radiology identified 10 common indications for computed tomography (CT) as part the Study on Clinical Diagnostic Reference Levels (DRLs, EUCLID), to help standardize radiation doses. objective this study is generate DRLs and median doses these using data from UCSF CT International Dose Registry.
The purpose of our study was to evaluate the efficacy CT histogram analysis for further characterization lipid-poor adenomas on unenhanced CT.One hundred thirty-two adrenal nodules were identified in 104 patients with lung cancer who underwent PET/CT. Sixty-five classified as lipid-rich if they had an attenuation less than or equal 10 H. Thirty-one masses greater H and stability more 1 year. Thirty-six metastases showed rapid growth year (n = 27) biopsy-proven 9). Histogram performed all...
To evaluate the capability of spectral computed tomography (CT) to improve characterization cystic high-attenuation lesions in a renal phantom and test hypothesis that CT will differentiation with high protein content those have undergone hemorrhage or malignant contrast-enhancing transformation.A contained grouped nonenhancing cyst series an iodine-enhancing was developed. Spectral is based on new detector designs may possess energy-sensitive photon-counting abilities, thereby facilitating...