Jira ChindasombatjaroenNaoya KakimotoHiroaki ShimamotoShumei MurakamiSouhei FurukawaOsaka UniversityMahidol University2018-05-032018-05-032011-09-01Journal of Computer Assisted Tomography. Vol.35, No.5 (2011), 662-66515323145036387152-s2.0-80053008019https://repository.li.mahidol.ac.th/handle/20.500.14594/12339Objectives: The study's objectives were to investigate the correlation between pixel values obtained from a cone-beam computed tomographic (CBCT) scanner and the computed tomographic (CT) values from a multidetector row CT scanner and to determine whether they have a linear relationship at various tube voltages and tube currents. Methods: A phantom with different concentrations of contrast medium at the center of a multidetector row CT and a CBCT scanner was scanned at various imaging parameters. Computed tomographic values and pixel values were measured using ImageJ. Regression analysis was performed, as well as correlation tests with a Pearson correlation coefficient. Results: A significant correlation between pixel values and the CT values of the same specimen was observed (P < 0.0001), and a linear relationship was found between the values from the 2 scanners at each parameter. Conclusions: A high correlation and linear relationship between the CT values and pixel values were found at each parameter. Therefore, linear functions can be used to convert a pixel value from the CBCT machine used in this study to the CT values. Copyright © 2011 by Lippincott Williams & Wilkins.Mahidol UniversityMedicineArticleSCOPUS10.1097/RCT.0b013e31822d9725