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http://dx.doi.org/10.7742/jksr.2020.14.6.811

MTF Evaluation according to change in posture and channel during CT examination for wrist Joint : X-axis and Z-axis changes around Isocenter  

Seo, Min Jae (Department of Radiological Sceience, Eulji University)
Lim, Jong Chon (Department of Radiological Sceience, Eulji University)
Jung, Dabin (Department of Radiological Science, Graduate school Eulji University)
Han, Dong Kyoon (Department of Radiological Sceience, Eulji University)
Publication Information
Journal of the Korean Society of Radiology / v.14, no.6, 2020 , pp. 811-817 More about this Journal
Abstract
This study aims to evaluate the Modulation Transfer Function (MTF) according to the change in the number of channels of the CT examination device by changing the posture of the patient to the X-axis and Y-axis in the wrist joint CT examination. Using a CT device and a wrist phantom, the test was performed by moving 0 (matched), 5, 10, and 15 cm in the X-axis around the isocenter, and the Z-axis was rotated by -20° and -40°. For the test, 16, -40 and 64 channels were used to check whether there was a difference for each number of channels. The examined images were compared by measuring the MTF values of the ulna and left and right sides of the radius. In the experiment where the isocenter was moved along the X-axis, the MTF value decreased with an increase in the moving distance, and the MTF value was found to be unaffected by the number of channels. In the experiment in which the wrist joint was rotated by -20° and -40° on the Z-axis, the degree of deviation and MTF were found to be irrelevant. It was not related to the number of channels either. In conclusion, the movement of the wrist along the X-axis should be restrained as much as possible for a wrist joint CT scan, whereas deviation around the Z-axis depending on the environment for the patient would not affect the MTF of the image.
Keywords
Wrist joint CT; Shifted X-axis; Rotated Z-axis; CT MTF; CT channel;
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1 C. D. Becker, P. A. Poletti, "The trauma concept:the role of MDCT in the diagnosis and management of visceral injuries", European Radiology Supplements, Vol. 15, No. 4, pp. d105-d109, 2005. http://dx.doi.org/10.1007/s10406-005-0122-9   DOI
2 M. Zlotorowicz, J. Czubak, A. Caban, P. Kozinski, R. Boguslawska-Walecka, "The blood supply to the femoral head after posterior fracutre/dislocation of the hip, assessed by CT angiography", The Bone & Joint Journal, Vol. 95-B, No. 11, pp. 1453-1457, 2013. http://dx.doi.org/10.1302/0301-620X.95B11.32383   DOI
3 MER. M. Patterson, MSK. W. Elder, MDS. F. Viegas, "Carpal bone anatomy measured by computer analysis of three-dimensional reconstructions of computed tomography images", The Journal of Hand Surgery, Vol. 20, No. 6, pp. 923-929, 1995. http://dx.doi.org/10.1016/S0363-5023(05)80138-8   DOI
4 J. F. Barrett, N. Keat, "Artifacts in CT: Recognition and Avoidance", Radiographis, Vol. 24, No. 6, pp. 1679-1691, 2004. http://dx.doi.org/10.1148/rg.246045065   DOI
5 H. W. Cho, K. S. Chon, "Change of MTF for Sampling Interval in Digital Detector", Journal of Korean Society of Radiology, Vol. 8. No. 5, pp. 225-230, 2014. http://dx.doi.org/10.7742/Jksr.2014.8.5.225   DOI
6 S. M. Elkhateeb, G. R. Torgersen, E. A. Amout, "Image quality assessement of clinically-applied CBCT protocols using a QAT phantom", Dentomaxillofacial Radiology, Vol. 45, No. 5, pp. 1-11, 2016. http://dx.doi.org/10.1259/dmfr.-20160075   DOI
7 I. Ali, S. Ahmad, "Evaluation of the effects of sagging shifts on isocenter accuracy and image quality of Cone-beam CT from kV on-board imagers", Journal of Applied Clinical Medical Physics, Vol. 10, No. 3, pp. 180-194, 2009. http://dx.doi.org/10.11-20/jacmp.v10i3.2930   DOI
8 T. Hara, K. Ichikawa, S. Sanada, Y. Ida, "Image quality dependence on in-plane ppositions and directions for MDCT images", European Journal of Radiology, Vol. 75, No. 1, pp. 114-121, 2010. http://dx.doi.org/10.1016/j.ejrad.-2009.03.060   DOI
9 O. O. Akin-Akintayo, L. F. Alexander, R. Neill. MS, E. A. Krupinksi, X. Tang, P. K. Mittal, W. C. Small, C. C. Moreno, "Prevalence and severity of off-centering during diagnostic CT:Observations from 57,621 CT scans if the Chest, Abdomen, and/or Pelvis", Current Problems in diagnostic Radiology, Vol. 48, No. 3, pp. 229-234, 2019. http://dx.doi.org/10.1067/j.cpradiol.-2018.02.007   DOI
10 B. G. Baumert, P. Egli, S. Studer, C. Dehing, J. B. Davis, "Repositioning accuracy of fractionated stereotactic irradiation:assessment of isocentre alignment for different dental fixations by using sequential CT scanning", Radiotherapy and Oncology, Vol. 74, No. 1, pp. 61-66, 2005. http://dx.doi.org/10.1016/j.radonc.-2004.08.002   DOI
11 S. J. Utrup, K. M. Brown, "Quanitfication and Elimination of Windmill Artifacts in Multi Slice CT", Medical imaging, Vol. 6913, pp. 691338, 2008. http://dx.doi.org/10.1117/12.773020   DOI
12 A. L. C. Kwan, J. M. Boone, K. Yang, S. Y. Huang, "Evaluation of the spatial resolution characteristics of a cone-beam breast CT scanner", Medical Physics, Vol. 34, No, 1, pp. 275-281, 2007. http://dx.doi.org/10.1118/1.2400830   DOI