Implications of patient centring on organ dose in computed tomography
Automatic exposure control (AEC) in computed tomography (CT) facilitates optimisation of dose absorbed by the patient. The use of AEC requires appropriate ‘patient centring’ within the gantry, since positioning the patient off-centre may affect both image quality and absorbed dose. The aim of this experimental study was to measure the variation in organ and abdominal surface dose during CT examinations of the head, neck/thorax and abdomen. The dose was compared at the isocenter with two off-centre positions—ventral and dorsal to the isocenter. Measurements were made with an anthropomorphic adult phantom a...
Source: Radiation Protection Dosimetry - June 6, 2016 Category: Radiology Authors: Kataria, B., Sandborg, M., Althen, J. N. Tags: Paper Source Type: research
Assessment of clinical image quality in paediatric abdominal ct examinations: dependency on the level of adaptive statistical iterative reconstruction (asir) and the type of convolution kernel
The purpose of this study was to investigate the effect of different combinations of convolution kernel and the level of Adaptive Statistical iterative Reconstruction (ASiR™) on diagnostic image quality as well as visualisation of anatomical structures in paediatric abdominal computed tomography (CT) examinations. Thirty-five paediatric patients with abdominal pain with non-specified pathology undergoing abdominal CT were included in the study. Transaxial stacks of 5-mm-thick images were retrospectively reconstructed at various ASiR levels, in combination with three convolution kernels. Four paediatric radiologists r...
Source: Radiation Protection Dosimetry - June 6, 2016 Category: Radiology Authors: Larsson, J., Bath, M., Ledenius, K., Caisander, H., Thilander-Klang, A. Tags: Paper Source Type: research
The effect of adaptive statistical iterative reconstruction on the assessment of diagnostic image quality and visualisation of anatomical structures in paediatric cerebral ct examinations
In this study, 60 % ASiR was found to be the optimal level of ASiR for paediatric cerebral CT examinations. This shows that the commonly used 30 % ASiR may not always be the optimal level. (Source: Radiation Protection Dosimetry)
Source: Radiation Protection Dosimetry - June 6, 2016 Category: Radiology Authors: Larsson, J., Bath, M., Ledenius, K., Thilander-Klang, A. Tags: Paper Source Type: research
COMPARISON OF ADAPTIVE STATISTICAL ITERATIVE RECONSTRUCTION (ASIR™) AND MODEL-BASED ITERATIVE RECONSTRUCTION (VEO™) FOR PAEDIATRIC ABDOMINAL CT EXAMINATIONS: AN OBSERVER PERFORMANCE STUDY OF DIAGNOSTIC IMAGE QUALITY
The diagnostic image quality of 75 paediatric abdominal computed tomography (CT) examinations reconstructed with two different iterative reconstruction (IR) algorithms—adaptive statistical IR (ASiR™) and model-based IR (Veo™)—was compared. Axial and coronal images were reconstructed with 70 % ASiR with the Soft™ convolution kernel and with the Veo algorithm. The thickness of the reconstructed images was 2.5 or 5 mm depending on the scanning protocol used. Four radiologists graded the delineation of six abdominal structures and the diagnostic usefulness of the image quality. The Veo reconstruct...
Source: Radiation Protection Dosimetry - June 6, 2016 Category: Radiology Authors: Hultenmo, M., Caisander, H., Mack, K., Thilander-Klang, A. Tags: Paper Source Type: research
Model-based iterative reconstruction enables the evaluation of thin-slice computed tomography images without degrading image quality or increasing radiation dose
In conclusion, IMR enables reduction of the slice thickness while maintaining or even improving image quality versus iDose4. (Source: Radiation Protection Dosimetry)
Source: Radiation Protection Dosimetry - June 6, 2016 Category: Radiology Authors: Aurumskjöld, M.-L., Ydström, K., Tingberg, A., Söderberg, M. Tags: Paper Source Type: research
