Impact of image noise levels, scout scan dose and lens shield on image quality and radiation exposure in z-axis dose-modulated neck MSCT on 16- and 64-slice Toshiba Aquilion scanners
Hans-Christian BauknechtCornelia JachGeorg BöhnerHenning MeyerChristian Scheurig‐MuenklerEberhard SiebertRandolf Klingebiel
2
Citation
15
Reference
10
Related Paper
Citation Trend
Keywords:
Image noise
Hounsfield scale
Image noise
Dose area product
Cite
Citations (9)
Image noise
Radon transform
Reconstruction algorithm
Cite
Citations (63)
Subtraction
Image subtraction
Digital subtraction angiography
Cite
Citations (4)
Objective To investigate the differences of image quality and radiation dose of chest CT between sinogram affirmed iterative reconstruction(SAFIRE)algorithm and filtered back projection(FBP)algorithm.Methods Three sets of tube voltage values of 80,100,120kV were defaulted.Using automatic mAs care dose 4Dtechnology,aphantom was scanned with new dual-source CT(Somatom definition flash).Data sets were reconstructed with FBP and SAFIRE(level 1—5),and the noise and CT values of different structures of chest were compared.Two radiologists evaluated the image quality independently.After each scanning,the dose weighted index(CTDIvol)and dose-length product(DLP)were recorded,then effective dose was calculated and compared.Results With the same scan condition,image noise of SAFIRE of chest CT was significantly lower than that of FBP(P0.05).Among different scan conditions,regardless of FBP algorithm or SAFIRE algorithm,image noise of chest CT went lower when tube voltage increased.Image noise of different structures of chest changed with different reconstruction algorithm and tube voltage.Both subjective and objective image quality indicators of 100kV/SAFIRE(level 3)were better than those of 120kV/FBP,and radiation dose reduced by 37.61%.Conclusion SAFIRE reconstruction algorithm can effectively improve image quality and reduce radiation dose in chest CT.
Image noise
Radon transform
Reconstruction algorithm
Cite
Citations (0)
In radiology, it is significantly important to produce adequate diagnostic information for affecting the patient with the lowest amount of dose. A contrast-detail phantom is generally used to study the quality of the image and the amount of radiation dose for a digital X-ray imaging system. For evaluating the quality of a phantom image, the radiologists are required to indicate the location of the holes in each square in the phantom image. Then, the image quality figure (IQF) of the image can be calculated. However, evaluation by the human eye is subjective and time-consuming. In this paper, an image processing based IQF evaluation method is proposed to automatically measure the quality of a phantom image. The experimental results tell that the proposed method is more sensitive in estimating the IQF of a phantom image than the observation of radiologists.
Digital radiography
Image contrast
Cite
Citations (0)
Radon transform
Neuroradiology
Interventional radiology
Image noise
Cite
Citations (100)
The aim of this work is to evaluate the characteristics involved in the image reconstruction of the microPET Focus 120. For this evaluation were used two different phantoms; a miniature hot‐rod Derenzo phantom and a National Electrical Manufacturers Association (NEMA) NU4‐2008 image quality (IQ) phantom. The best image quality was obtained when using OSEM3D as the reconstruction method reaching a spatial resolution of 1.5 mm with the Derenzo phantom filled with 18F. Image quality test results indicate a superior image quality for the Focus 120 when compared to previous microPET models.
Cite
Citations (0)
An automated closed-loop dose control system balances the radiation dose delivered to patients and the quality of images produced in cardiac x-ray imaging systems. Using computer simulations, this study compared two designs of automatic x-ray dose control in terms of the radiation dose and quality of images produced. The first design, commonly in x-ray systems today, maintained a constant dose rate at the image receptor. The second design maintained a constant image quality in the output images. A computer model represented patients as a polymethylmetacrylate phantom (which has similar x-ray attenuation to soft tissue), containing a detail representative of an artery filled with contrast medium. The model predicted the entrance surface dose to the phantom and contrast to noise ratio of the detail as an index of image quality. Results showed that for the constant dose control system, phantom dose increased substantially with phantom size (x5 increase between 20 cm and 30 cm thick phantom), yet the image quality decreased by 43% for the same thicknesses. For the constant quality control, phantom dose increased at a greater rate with phantom thickness (>x10 increase between 20 cm and 30 cm phantom). Image quality based dose control could tailor the x-ray output to just achieve the quality required, which would reduce dose to patients where the current dose control produces images of too high quality. However, maintaining higher levels of image quality for large patients would result in a significant dose increase over current practice.
Cardiac Imaging
Cite
Citations (0)
Helical scan
Image noise
Computed tomographic angiography
Cite
Citations (18)
Objective: The aim of the study was to examine how to decrease of radiation dose caused by CT in PET/CT while ensuring quality of CT image.Methods: PET/CT(GE Discovery ST16),Catphan 500,different scan conditions,total 30 groups.The image quality was evaluated by high resolution、low contrast、uniformity、noise.CTDIw and CTDIvol were calculated.The relationship between CT image quantity and CT dose was analyzed.Results: CT dose was related to uniformity,but not to high resolution.The low contrast of CT image improved with the increasing of CT dose.And the decrease of noise with the increase of CT dose was showed with an expression.Conclusions: The radiation dose by CT in PET/CT could be decreased appropriately under the guarantee of the quality of the CT image.
Image noise
PET-CT
Cite
Citations (1)