Image quality criteria for wide-field x-ray imaging applications

1999 ◽  
Author(s):  
Patrick L. Thompson ◽  
James E. Harvey
2011 ◽  
Vol 15 (3) ◽  
pp. 70 ◽  
Author(s):  
Geoffrey K Korir ◽  
Jeska Sidika Wambani ◽  
Ian K Korir

Background. The wide use of ionising radiation in medical care has resulted in the largest man-made cause of radiation exposure. In recent years, diagnostic departments in Kenya have adapted the high-speed film/screen combination without well-established quality control, objective image quality criteria, and assessment of patient dose. The safety of patients in terms of justification and the as-low-as-reasonably-achievable (ALARA) principle is inadequate without quality assurance measures. Aim. This study assessed the level of film rejects, device performance, image quality and patient dose in 4 representative hospitals using high-speed film/screen combination. Results. The X-ray equipment quality control tests performance range was 67% to 90%, and 63% of the radiographs were of good diagnostic value. The measured prevalent chest examination entrance surface dose (ESD) showed levels above the international diagnostic reference levels (DRLs), while lumbar spine and pelvis examination was the largest source of radiation exposure to patients. Conclusion. The optimisation of patient protection can be achieved with optimally performing X-ray equipment, the application of good radiographic technique, and continuous assessment of radiographic image quality.


2020 ◽  
Vol 43 (3) ◽  
pp. 765-779
Author(s):  
Zoe Brady ◽  
Heather Scoullar ◽  
Ben Grinsted ◽  
Kyle Ewert ◽  
Helen Kavnoudias ◽  
...  

2018 ◽  
Vol 25 (4) ◽  
pp. 1093-1105
Author(s):  
Yanping Wang ◽  
Gang Li ◽  
Jie Zhang ◽  
Qiru Yi ◽  
Yue Zhao ◽  
...  

Lens-coupled indirect X-ray imaging detectors have the advantage of high resolution and the disadvantage of low detection efficiency. Using thicker single-crystalline films (SCFs) can improve the detection efficiency. However, the image quality will become worse due to the degradation of the point spread function (PSF) and modulation transfer function (MTF). This disadvantage can be improved by deconvolution with the PSF, which is unknown. In this article, a method was established to acquire the PSF based on a simulation of the imaging process for a lens-coupled indirect X-ray imaging detector. Because the structural parameters of commercial lenses cannot usually be obtained, the PSFs were calculated from lens performance parameters. PSFs were calculated using the conditions of 12 keV X-ray energy, 10× and 40× magnification objectives and 4.6 µm- and 20 µm-thick GGG:Tb scintillators. These were then used to deconvolve images of an Xradia resolution test pattern taken under the same conditions. The results show that after deconvolution the MTF had been clearly improved for both the 4.6 µm- and 20 µm-thick SCFs, indicating that the image has better quality than before deconvolution. Furthermore, a PSF deconvolution was performed on mouse brain tissue projection images, and the original and deconvolution projection images were used to perform computed-tomography reconstruction; the result proved that the method was effective for improving the image quality of low-contrast samples. Therefore, this method shows promise in allowing the use of thick SCFs to improve the detection efficiency while maintaining good image quality.


1998 ◽  
Vol 14 (2) ◽  
pp. 75-83 ◽  
Author(s):  
Yoshiko Ariji ◽  
Jin-ichi Takahashi ◽  
Osamu Matsui ◽  
Tsuneichi Okano ◽  
Munetaka Naitoh ◽  
...  

2004 ◽  
Author(s):  
Paolo Conconi ◽  
Giovanni Pareschi ◽  
Sergio Campana ◽  
Guido Chincarini ◽  
Gianpiero Tagliaferri
Keyword(s):  
X Ray ◽  

2016 ◽  
Author(s):  
Kazuki Yoshida ◽  
Daisuke Yonetoku ◽  
Tatsuya Sawano ◽  
Hirokazu Ikeda ◽  
Atsushi Harayama ◽  
...  

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