The Study on Automatized Quantitative Assessment Method of CT Image in Quality Control : Focusing on Spatial and Low Contrast Resolution

Author(s):  
Ki Baek Lee ◽  
Yong Bum Cho ◽  
Hyun Keun Jeong ◽  
Ki Chang Nam ◽  
Ho Chul Kim
2018 ◽  
Vol 52 ◽  
pp. 61-62
Author(s):  
Bartosz Pawalowski ◽  
Hubert Szweda ◽  
Piotr Romanski ◽  
Krzysztof Matuszewski ◽  
Urszula Sobocka-Kurdyk ◽  
...  

2019 ◽  
Vol 7 (3) ◽  
Author(s):  
Igor Fernando Modesto Garcia ◽  
Paulo Mauricio Almeida Geambastiani ◽  
Mário De Jesus Ferreira ◽  
Eric Matos Macedo ◽  
Marcus Vínicius Teixeira Navarro ◽  
...  

Evaluate the performance of the monitors used for diagnosis based on the parameters defined by AAMP. Materials and Methods: Using calibrated instrumentation traceable to NIST and RBC, were evaluated in 15 monitors, according to the procedures described in AAMP's report 03 and the Spanish protocol in the following parameters: the general aspects of image quality, geometric distortion, screen reflection and room illumination, luminance response, luminance dependence, spatial and low contrast resolution, noise, internal reflection blanking and screen chromaticity. Results: 100% compliance for geometric distortion tests and 0% compliance for the luminance dependence test. Conclusions: There are nonspecific monitors for diagnosis being used for these purposes, without routinely checking tests, in rooms with high illumination and dirt on the screens and the non-implementation or inadequacy of acceptance and quality control tests. The monitors declared by the manufacturers as diagnostic specific on average showed a higher compliance rate


Author(s):  
Ye-Won Park Et.al

Background/Objectives: Quality control can improve the quality of medical care along with the stability of diagnostic X-ray generator. Regular quality control provides reliable quality control of the machine and maintains consistency of general imaging using radiation for efficient diagnosis. Methods/Statistical analysis: A phantom for quality control of diagnostic X-ray generator was produced using a 3D printer. Quantitative and qualitative evaluation of the phantom utility was conducted by modifying images acquired using S and D companies’ tools with Source to Image-Receptor Distance (SID) levels ranging between 130 cm and 180 cm. The evaluation indices were determined based on the analysis of field compliance, uniformity, low and high-contrast resolution, and linearity. Findings: The evaluation was conducted by acquiring and changing the radiographic image to SIDs between 130 cm and 180 cm using the indigenous phantom. The field compliance of S and D companies in terms of quantitative evaluation indices was both appropriate within ± 1% according to the SID change. To ensure a uniform SID 130 cm, the internal and external means of S company were 893 and 943, respectively, while those of the D company were 228.1 and 261.4, respectively. At an SID of 180 cm, the internal and external means of the S company were 928.1 and 958.4, respectively, while those of the D company were 257.2 and 299, respectively. A characteristic of the DR system was identified to ensure linearity, altered exposure dosage according to the step wedge height, and the difference in SI values according to the characteristics of the equipment and linearity. The qualitative evaluation indices were determined by identifying the size of the hole under high-contrast resolution up to 0.8㎜ and the bar size up to 1.6 lp/㎜. The low contrast resolution was evaluated with a C-D pattern, and at SID 130 cm, the S company scored 124.6 points and the D company 116 points, and at 180 cm, the S company scored 111.4 and the D company 104.6 points. Improvements/Applications: The utility of the homegrown phantom in quality control was confirmed for each index. The medical institutions are required to introduce quality control regulations for general image examination using radiation. It is helpful to efficiently manage old equipment and improve public health and medical care by linking with the health insurance fee.


2021 ◽  
Vol 11 (8) ◽  
pp. 3570
Author(s):  
Ki Baek Lee ◽  
Ki Chang Nam ◽  
Ji Sung Jang ◽  
Ho Chul Kim

Computed tomography (CT) quality control (QC) is regularly performed with standard phantoms, to bar faulty equipment from medical use. Its accuracy may be improved by replacing qualitative methods based on good visual distinction with pixel value-based quantitative methods. We hypothesized that statistical texture analysis (TA) that covers the entire phantom image would be a more appropriate tool. Therefore, our study devised a novel QC method based on the TA for contrast resolution (CR) and spatial resolution (SR) and proposed new, quantitative CT QC criteria. TA of CR and SR images on an American Association of Physicists in Medicine (AAPM) CT Performance Phantom were performed with nine CT scanner models. Six texture descriptors derived from first-order statistics of grayscale image histograms were analyzed. Principal component analysis was used to reveal descriptors with high utility. For CR evaluation, contrast and softness were the most accurate descriptors. For SR evaluation, contrast, softness, and skewness were the most useful descriptors. We propose the following ranges: contrast for CR, 29.5 ± 15%, for SR, 29 ± 10%; softness for CR, <0.015, for SR, <0.014; and skewness for SR, >−1.85. Our novel TA method may improve the assessment of CR and SR of AAPM phantom images.


Procedia CIRP ◽  
2021 ◽  
Vol 98 ◽  
pp. 49-54
Author(s):  
Sota Onozuka ◽  
Yusuke Kishita ◽  
Mitsutaka Matsumoto ◽  
Michikazu Kojima ◽  
Yasushi Umeda

2021 ◽  
Vol 66 (6) ◽  
pp. 374-378
Author(s):  
L. V. Domotenko ◽  
T. P. Morozova ◽  
A. P. Shepelin ◽  
A. Yu. Mironov

The aim of the study is to assess the effectiveness of quality control of transport environments in accordance with the requirements of domestic and international standards using aerobic and optional anaerobic microorganisms. The results of a comparative assessment of the survival of 10 strains of aerobic and optional anaerobic microorganisms after storage in the semi-liquid transport environment of Ames for 24 and 48 hours at temperatures (4-8)0 C and (20-25)0 C in accordance with the requirements of domestic and international standards are presented. The methodology described in ICC 4.2.2316 causes a number of technical difficulties leading to non-reproducible results. The survival rate of microorganisms in semi-liquid transport environments under ISO 11133-2016 is of high quality. The quantitative assessment is based on two Swab Elution and Roll Plate methods recommended by the CLSI M40-A2 standard.


2008 ◽  
Vol 32 (7) ◽  
pp. 561-568 ◽  
Author(s):  
Jong-Chan Lee ◽  
Kwan-Soo Kim ◽  
Jong-Hyung Yim ◽  
Hyo-Won Lee ◽  
Young-Min Kwon ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document