|
|
||||||||
Medical Physics |
1 From the Department of Radiology, SUNY Upstate Medical University, 750 E Adams St, Syracuse, NY 13210. Received December 28, 1999; revision requested February 21, 2000; revision received April 18; accepted May 1. Address correspondence to W.H. (e-mail: hudaw@mail.upstate.edu).
PURPOSE: To investigate how changes in kilovolt peak and milliampere second settings, and patient weight affect transmitted x-ray energy fluence and the image contrast-to-noise ratio (CNR) at abdominal computed tomography (CT).
MATERIALS AND METHODS: Cylinders of water were used as patient models, and x-ray spectra, including x-ray tube potentials of 80140 kVp, were investigated. The mean photon energy and energy fluence transmitted through water cylinders with varying diameters and the image contrast for fat, muscle, bone, and iodine relative to water were determined. The effect of changing the x-ray tube potential on CNR also was investigated.
RESULTS: At a constant kVp, increasing patient weight from 10 kg to 120 kg reduced the transmitted energy fluence by two orders of magnitude. Changing the x-ray tube potential from 80 kVp to 140 kVp increased the mean photon energy from approximately 52 keV to approximately 72 keV and thus reduced the image contrast relative to water by 12% for muscle, 21% for fat, 39% for bone, and 50% for iodine (approximate reduction values). Increasing the x-ray tube potential from 80 kVp to 140 kVp increased the CNR by a factor of 2.6 for muscle and by a factor of 1.4 for iodine.
CONCLUSION: With changes in patient weight at abdominal CT, x-ray tube potentials must be varied to maintain a constant detector energy fluence. Increasing the x-ray tube potential generally improves CNR.
Index terms: Abdomen, CT, 70.12111 Dosimetry, 70.12111 Computed tomography (CT), image quality, 70.12111 Computed tomography (CT), physics, 70.12111 Computed tomography (CT), radiation exposure, 70.12111 Radiations, exposure to patients and personnel
This article has been cited by other articles:
![]() |
Z. J. Wang, F. V. Coakley, Y. Fu, B. N. Joe, S. Prevrhal, L. A. Landeras, E. M. Webb, and B. M. Yeh Renal Cyst Pseudoenhancement at Multidetector CT: What Are the Effects of Number of Detectors and Peak Tube Voltage? Radiology, September 1, 2008; 248(3): 910 - 916. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Herzog, D. M. Mulvihill, S. A. Nguyen, G. Savino, B. Schmidt, P. Costello, T. J. Vogl, and U. J. Schoepf Pediatric Cardiovascular CT Angiography: Radiation Dose Reduction Using Automatic Anatomic Tube Current Modulation Am. J. Roentgenol., May 1, 2008; 190(5): 1232 - 1240. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. T. Hsu, Z. J. Wang, A. S. L. Yu, R. G. Gould, Y. Fu, B. N. Joe, A. Qayyum, R. S. Breiman, F. V. Coakley, and B. M. Yeh Physiology of Renal Medullary Tip Hyperattenuation at Unenhanced CT: Urinary Specific Gravity and the NaCl Concentration Gradient Radiology, April 1, 2008; 247(1): 147 - 153. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. Husmann, I. Valenta, O. Gaemperli, O. Adda, V. Treyer, C. A. Wyss, P. Veit-Haibach, F. Tatsugami, G. K. von Schulthess, and P. A. Kaufmann Feasibility of low-dose coronary CT angiography: first experience with prospective ECG-gating Eur. Heart J., January 2, 2008; 29(2): 191 - 197. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. T. Schindera, R. C. Nelson, S. Mukundan Jr, E. K. Paulson, T. A. Jaffe, C. M. Miller, D. M. DeLong, K. Kawaji, T. T. Yoshizumi, and E. Samei Hypervascular Liver Tumors: Low Tube Voltage, High Tube Current Multi Detector Row CT for Enhanced Detection Phantom Study Radiology, December 1, 2007; 246(1): 125 - 132. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. L. Hollingsworth, T. T. Yoshizumi, D. P. Frush, F. P. Chan, G. Toncheva, G. Nguyen, C. R. Lowry, and L. M. Hurwitz Pediatric Cardiac-Gated CT Angiography: Assessment of Radiation Dose Am. J. Roentgenol., July 1, 2007; 189(1): 12 - 18. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. Hur, S. W. Hong, S. Y. Kim, Y. H. Kim, Y. J. Hwang, W. R. Lee, and S. J. Cha Uniform Image Quality Achieved by Tube Current Modulation Using SD of Attenuation in Coronary CT Angiography Am. J. Roentgenol., July 1, 2007; 189(1): 188 - 196. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. H. Fahey, M. R. Palmer, K. J. Strauss, R. E. Zimmerman, R. D. Badawi, and S. T. Treves Dosimetry and Adequacy of CT-based Attenuation Correction for Pediatric PET: Phantom Study Radiology, April 1, 2007; 243(1): 96 - 104. [Abstract] [Full Text] [PDF] |
||||
![]() |
W. Huda and A. Vance Patient Radiation Doses from Adult and Pediatric CT Am. J. Roentgenol., February 1, 2007; 188(2): 540 - 546. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. V. Sahani, S. P. Kalva, P. F. Hahn, and S. Saini 16-MDCT Angiography in Living Kidney Donors at Various Tube Potentials: Impact on Image Quality and Radiation Dose Am. J. Roentgenol., January 1, 2007; 188(1): 115 - 120. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. C. Dalrymple, S. R. Prasad, F. M. El-Merhi, and K. N. Chintapalli Price of Isotropy in Multidetector CT RadioGraphics, January 1, 2007; 27(1): 49 - 62. [Abstract] [Full Text] [PDF] |
||||
![]() |
W. C. Chan, B. N. Joe, F. V. Coakley, E. L. Prien Jr, R. G. Gould, S. Prevrhal, W. C. Barber, K. S. Kirkwood, A. Qayyum, and B. M. Yeh Gallstone Detection at CT in Vitro: Effect of Peak Voltage Setting. Radiology, November 1, 2006; 241(2): 546 - 553. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. Nakayama, K. Awai, Y. Funama, D. Liu, T. Nakaura, Y. Tamura, and Y. Yamashita Lower tube voltage reduces contrast material and radiation doses on 16-MDCT aortography. Am. J. Roentgenol., November 1, 2006; 187(5): W490 - W497. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Hausleiter, T. Meyer, M. Hadamitzky, E. Huber, M. Zankl, S. Martinoff, A. Kastrati, and A. Schomig Radiation Dose Estimates From Cardiac Multislice Computed Tomography in Daily Practice: Impact of Different Scanning Protocols on Effective Dose Estimates Circulation, March 14, 2006; 113(10): 1305 - 1310. [Abstract] [Full Text] [PDF] |
||||
![]() |
V. L. Ward, C. E. Barnewolt, K. J. Strauss, R. L. Lebowitz, V. Venkatakrishnan, M. Stehr, D. L. McLellan, C. A. Peters, D. Zurakowski, P. S. Dunning, et al. Radiation Exposure Reduction during Voiding Cystourethrography in a Pediatric Porcine Model of Vesicoureteral Reflux Radiology, January 1, 2006; 238(1): 96 - 106. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. H. McCollough Automatic Exposure Control in CT: Are We Done Yet? Radiology, December 1, 2005; 237(3): 755 - 756. [Full Text] [PDF] |
||||
![]() |
Y. Funama, K. Awai, Y. Nakayama, K. Kakei, N. Nagasue, M. Shimamura, N. Sato, S. Sultana, S. Morishita, and Y. Yamashita Radiation Dose Reduction without Degradation of Low-Contrast Detectability at Abdominal Multisection CT with a Low-Tube Voltage Technique: Phantom Study Radiology, December 1, 2005; 237(3): 905 - 910. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Menke Comparison of Different Body Size Parameters for Individual Dose Adaptation in Body CT of Adults Radiology, August 1, 2005; 236(2): 565 - 571. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Irie and H. Inoue Individual Modulation of the Tube Current-Seconds to Achieve Similar Levels of Image Noise in Contrast-Enhanced Abdominal CT Am. J. Roentgenol., May 1, 2005; 184(5): 1514 - 1518. [Abstract] [Full Text] [PDF] |
||||
![]() |
W. D. Middleton, S. A. Teefey, and K. Yamaguchi Sonography of the Rotator Cuff: Analysis of Interobserver Variability Am. J. Roentgenol., November 1, 2004; 183(5): 1465 - 1468. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. J. Siegel, B. Schmidt, D. Bradley, C. Suess, and C. Hildebolt Radiation Dose and Image Quality in Pediatric CT: Effect of Technical Factors and Phantom Size and Shape Radiology, November 1, 2004; 233(2): 515 - 522. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Saini Multi-Detector Row CT: Principles and Practice for Abdominal Applications Radiology, November 1, 2004; 233(2): 323 - 327. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. D. Cody, D. M. Moxley, K. T. Krugh, J. C. O'Daniel, L. K. Wagner, and F. Eftekhari Strategies for Formulating Appropriate MDCT Techniques When Imaging the Chest, Abdomen, and Pelvis in Pediatric Patients Am. J. Roentgenol., April 1, 2004; 182(4): 849 - 859. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. B. Sigal-Cinqualbre, R. Hennequin, H. T. Abada, X. Chen, and J.-F. Paul Low-Kilovoltage Multi-Detector Row Chest CT in Adults: Feasibility and Effect on Image Quality and Iodine Dose Radiology, April 1, 2004; 231(1): 169 - 174. [Abstract] [Full Text] [PDF] |
||||
![]() |
J Pages, N Buls, and M Osteaux CT doses in children: a multicentre study Br. J. Radiol., November 1, 2003; 76(911): 803 - 811. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. M. Boone, E. M. Geraghty, J. A. Seibert, and S. L. Wootton-Gorges Dose Reduction in Pediatric CT: A Rational Approach Radiology, August 1, 2003; 228(2): 352 - 360. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. F. McNitt-Gray AAPM/RSNA Physics Tutorial for Residents: Topics in CT: Radiation Dose in CT RadioGraphics, November 1, 2002; 22(6): 1541 - 1553. [Abstract] [Full Text] [PDF] |
||||
![]() |
A Khursheed, M C Hillier, P C Shrimpton, and B F Wall Influence of patient age on normalized effective doses calculated for CT examinations Br. J. Radiol., October 1, 2002; 75(898): 819 - 830. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. E. van Gelder, H. W. Venema, I. W. O. Serlie, C. Y. Nio, R. M. Determann, C. A. Tipker, F. M. Vos, A. S. Glas, J. F. W. Bartelsman, P. M. M. Bossuyt, et al. CT Colonography at Different Radiation Dose Levels: Feasibility of Dose Reduction Radiology, July 1, 2002; 224(1): 25 - 33. [Abstract] [Full Text] |
||||
![]() |
D. P. Frush, B. Soden, K. S. Frush, and C. Lowry Improved Pediatric Multidetector Body CT Using a Size-Based Color-Coded Format Am. J. Roentgenol., March 1, 2002; 178(3): 721 - 726. [Abstract] [Full Text] [PDF] |
||||
![]() |
G Starck, L Lonn, A Cederblad, E Forssell-Aronsson, L Sjostrom, and M Alpsten A method to obtain the same levels of CT image noise for patients of various sizes, to minimize radiation dose Br. J. Radiol., February 1, 2002; 75(890): 140 - 150. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. G. Ravenel, E. M. Scalzetti, W. Huda, and W. Garrisi Radiation Exposure and Image Quality in Chest CT Examinations Am. J. Roentgenol., August 1, 2001; 177(2): 279 - 284. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| RADIOLOGY | RADIOGRAPHICS | RSNA JOURNALS ONLINE |