Implementation of Standard Deviation Map (SDM) for an Automation of Spatial Resolution Measurements on Computed Tomography Images of ACR CT Accreditation Phantom

Authors

  • Didik Rahmadi  Department of Physics, Faculty of Sciences and Mathematics, Diponegoro University, Jl. Prof Soedarto SH, Tembalang, Semarang, Central Java, Indonesia
  • Choirul Anam  Department of Physics, Faculty of Sciences and Mathematics, Diponegoro University, Jl. Prof Soedarto SH, Tembalang, Semarang, Central Java, Indonesia
  • Eko Hidayanyo  Department of Physics, Faculty of Sciences and Mathematics, Diponegoro University, Jl. Prof Soedarto SH, Tembalang, Semarang, Central Java, Indonesia
  • Ariij Naufal  

DOI:

https://doi.org/10.32628/IJSRST52310237

Keywords:

CT scanner, ACR CT accreditation phantom, reconstruction filter, automatic, spatial resolution

Abstract

This study is to develop an automated method to determine the spatial resolution of computed tomography (CT) images on line-pair objects of the American College of Radiology (ACR) CT accreditation phantom. The ACR phantom was scanned using a GE Healthcare 128-slice CT scanner with seven different reconstruction filters of E1, E2, E3, LU, S1, S2, S3. The automated method involved building a standard deviation map (SDM), segmenting the line-pair objects within SDM images, determining the region of interest (ROI) within line pair object, and determining a resolvable line-pair object with dynamic threshold which is dependent on image noise. The scanning parameters were fixed at 120 kVp and 160 mAs. The results of automated method were compared with those from manual measurements performed by five human observers. The automatic method produced spatial resolution results of 0.7, 0.7, 0.7, 0.7, 0.6, 0.6, and 0.6 lp/mm for filters E1, E2, E3, LU, S1, S2, and S3, respectively, while the manual measurements yielded results of 0.6, 0.6, 0.6, 0.7, 0.6, 0.5, and 0.5 lp/mm. The differences between the manual and automatic measurement results were small, with a maximum difference of 0.1 lp/mm. Hence, the automatic measurement of spatial resolution on line-pair objects of the ACR CT accreditation phantom is a feasible and reliable method.

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International Journal of Scientific Research in Science and Technology

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Published

2023-04-30

Issue

Volume 10, Issue 2, March-April-2023

Section

Research Articles

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How to Cite

[1]
Didik Rahmadi, Choirul Anam, Eko Hidayanyo, Ariij Naufal "Implementation of Standard Deviation Map (SDM) for an Automation of Spatial Resolution Measurements on Computed Tomography Images of ACR CT Accreditation Phantom" International Journal of Scientific Research in Science and Technology(IJSRST), Online ISSN : 2395-602X, Print ISSN : 2395-6011,Volume 10, Issue 2, pp.256-262, March-April-2023. Available at doi : https://doi.org/10.32628/IJSRST52310237