Introduction: To investigate how ASiR-V and kVp changes in Computed tomography (CT) affect radiation dose and image quality, when using automatic tube current modulation (ATCM) for different sized phantoms.
Methods: A liver-phantom with two different liver inserts (QRM, Moehrendorf, Germany), with extension rings, representing fat, were additionally applied to the phantom to simulate patients of different sizes (small: 30cm diameter, medium: 35cm and large: 40cm). Abdominal scans were performed on a 256 slice CT scanner (GE Healthcare, Milwaukee, WI, USA), with consistent pitch (0.992), rotation time (0.5s), slice thickness (0.625mm) and collimation (80mm), while other parameters were varied (kVp: 80/100/120/140; Noise Index: 13/22; mA interval 80-720, ASiR-V: 30/60/100%). CTDI and DLP was recorded for each scan and image quality was assessed using objective metrics in predefined anatomic areas (HU and noise). Radiation dose and image quality metrics were compared between protocols.
Results: CTDI decreased by 80% from ASIR-V 30% to ASiR-V 100% for prescribed NI 13, and by 79% for the prescribed NI of 22. For 100% ASiR-V and a prescribed NI of 22 the CTDI remained the same regardless of phantom size for the different kVp settings. Pairwise comparison revealed significant differences in CTDI (p < 0.0001) for all combinations of prescribed NI and ASIR-V levels, except the difference between ASIR-V levels of 30 and 60%, with a prescribed NI of 13 (p = 0.124). When data from the three phantom sizes were combined, increasing ASIR-V from 30-100%, resulted in noise decreases of 22% for NI of 13 and by 8% for NI of 22. Notably, image quality in the low contrast area of the liver insert was impaired when the large phantom was scanned with 100% ASiR-V and either 80/100kVp (NI 22), because of the large reduction in tube current applied (down to 80 mA).
Conclusion: Substantial radiation dose reductions (up to 80%) resulted from increasing ASiR-V levels. However, image quality deteriorates when 100% ASiR-V is applied due to low applied tube current by the ATCM.
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http://dx.doi.org/10.1016/j.jmir.2022.06.008 | DOI Listing |
JAMA Netw Open
January 2025
Medical Oncology, The Ottawa Hospital Cancer Centre, University of Ottawa Faculty of Medicine, Ottawa, Ontario, Canada.
Importance: Evolving breast cancer treatments have led to improved outcomes but carry a substantial financial burden. The association of treatment costs with the cost-effectiveness of screening mammography is unknown.
Objective: To determine the cost-effectiveness of population-based breast cancer screening in the context of current treatment standards.
EJNMMI Phys
January 2025
Department of Nuclear Medicine, Lanzhou University Second Hospital, Lanzhou, 730030, China.
Purpose: The aim of the study was to investigate the value of SwiftScan Step-and-Shoot Continuous (SSC) scanning mode in enhancing image quality and to explore appropriate scanning parameters for reducing scan time.
Methods: This study was composed of a phantom study and two clinical tests. The differences in visual image quality scores, coefficient of variance (COV) of the background, image signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and recovery coefficient (RC) of the sphere were compared between SSC mode and traditional Step-and-Shoot (SS) mode in the phantom study.
Neurol Sci
January 2025
International Ph.D. Program in Medicine, College of Medicine, Taipei Medical University, Taipei, 110, Taiwan.
Objectives: Fibromyalgia imposes a considerable burden of disability worldwide, and its therapies include rehabilitation interventions. However, the overall brain modulatory effects of rehabilitation interventions and their effects on clinical improvements in patients with fibromyalgia remain unclear. This systematic review of magnetic resonance imaging studies synthesised evidence for the brain modulatory effects of rehabilitation in patients with fibromyalgia.
View Article and Find Full Text PDFFollowing fracture fixation, fracture-related infection (FRI) is a common complication and requires systematic evaluation to allow for an optimal treatment strategy. A high index of suspicion is necessary for early and timely diagnosis, to diagnose occult infection, and to prevent untreated infections from worsening. Diagnosis of FRI includes evaluation based on history and clinical examination, surgical exploration, serum inflammatory markers, imaging modalities, microbiology, histopathology, and, when needed, molecular biology.
View Article and Find Full Text PDFJ Med Radiat Sci
January 2025
Discipline of Medical Imaging Sciences, Faculty of Medicine and Health, University of Sydney, Camperdown, New South Wales, Australia.
Introduction: Quality assurance (QA) in medical imaging ensures consistently high-quality images at acceptable radiation doses. However, the applicability of the chest X-ray (CXR) QA tool in images with pathology, particularly infectious diseases like COVID-19, has not been explored. This study examines the utility of the European Guidelines for image quality in QA of CXRs with varying severity and types of infectious disease.
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