Correlation of Volume Computed Tomography Dose Index and Dose Length Product with Acquisition Parameters in Abdomino-pelvic and Cranial Computed Tomography Imaging
Published: 2023-03-13
Page: 64-71
Issue: 2023 - Volume 6 [Issue 1]
Ezinma Helen O.
Department of Radiology, University College Hospital, Ibadan, Oyo State, Nigeria.
Owoade Latifat R. *
National Institute of Radiation Protection and Research, Nigerian Nuclear Regulatory Authority, University of Ibadan, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
Introduction: The use of Computed Tomography (CT) in medical diagnosis showing more complex fractures and other pathological findings in 3D, delivers relatively higher radiation doses to patients when compared to conventional X-rays. In order to maintain good diagnosis while reducing patients’ dose, it is necessary to assess the contributions of CT scan acquisition parameters (kV, mAs and scan length) to patient dose, and improve the selection of those parameters. This work aimed at investigating the relationship between the Volume CT Dose Index (CTDIvol) and Dose Length Product (DLP) with scan acquisition parameters in other to establish the Correlation of CTDIvol and DLP with scan acquisition parameters in Abdomino-Pelvic and Cranial CT.
Methodology: A total of 61 existing patients’ data with scan acquisition parameters were collected: Cranial CT (39) and Abdomino-pelvic CT (22). Pearson correlation analysis was used to establish the relationship between scan acquisition parameters and Total CTDIvol and Total DLP.
Results: The Total CTDIvol ranged from 135.6 to 215.5 mGy for cranial CT and 26.1 to 124.4 mGy for Abdomino-pelvic, while DLP ranged from 2631.0 to 6542.8 mGy.cm for cranial and 1147.5 to 5441.8 mGy.cm for Abdomino-pelvic.
The CTDIvol showed moderate positive correlation with kV (r = 0.625, P value ˂ 0.01) for Cranial and strong positive correlation (r = 0.821, P value ˂ 0.01) for Abdomino-pelvic CT, while DLP showed strong positive correlation (r = 0.767 and 0.839, P value ˂ 0.01) for both Cranial and Abdomino-pelvic. The CTDIvol and DLP showed strong positive correlation with mAs (r = 0.843 and 0.839, P value ˂ 0.01) for both cranial and abdomino-pelvic CT. CTDIvol and DLP showed a strong positive correlation with scan length (r= 0.712 and 0.881, P value ˂ 0.001) for both Cranial and Abdomino-pelvic CT. Increase in kV, mAs and scan length may cause significant increase in CTDIvol and DLP in Cranial and Abdomino-pelvic CT.
Conclusion: The relationships between CTDIvol and DLP with scan acquisition parameters in adult patients have been investigated for both Cranial CT and Abdomino-pelvic CT. It was observed that scan acquisition parameters (kV, mAs and Scan length) had linear relationship with CTDIvol and DLP in both investigations.
Keywords: Computed tomography, correlation, Volume Computed Tomography Dose Index (CTDIvol.), Dose Length Product (DLP), Abdomino-pelvic CT scans
How to Cite
Downloads
References
Smith-Bindman R, Miglioretti DL, Larson EB. Rising use of diagnostic medical imaging in a large integrated health system. Health Aff Millwood). 2008;27(6): 1491-1502.
Huda W. Radiation dosimetry in CT: The role of the manufacturer. Imaging Medical. 2011;3(2):241-259.
Yu L, Liu X, Leng S, Kofler JM, Ramirez-Giraldo JC, Qu M, Christner J, et al. Radiation dose reduction in computed tomography: Techniques and future perspective. Imaging Medical. 2009;1(1): 65-84.
Bjorkdahl P, Nyma U. Using 100 – instead of 120 kVp computed tomography to diagnose pulmonary embolism almost halves the radiation dose with preserved diagnostic quality. Acta Radiologica. 2010;51(3):260-270.
Christner JA, Braun NN, Jacobsen MC, Carter RE, Kofler JM, McCollough CH. Size-specific dose estimates for adult patients at computed tomography of the torso. Radiology. 2012;265(3):841-847.
Israel GM, Cicchiello L, Brink J, Huda W. Patient size and radiation exposure in thoracic, pelvic and abdominal computed tomography examinations performed with automatic exposure control. AJR Am J Roentgenol. 2010;195(6):1342-1346.
Zarb F, Ranford L, Mc Entee MF. Antero-posterior diameter shows the strongest correlation with CTDI and DLP in abdominal and chest computed tomography. Radiation Protection Dosimetry. 2010;(2):1-8.
Aweda MA, Arogundade RA. Patient dose reduction methods in computerised tomography procedures: A review. International Journal of Physical Sciences. 2007;2(1):001-009.
Goldman LW. Principles of computed tomography: Radiation dose and image quality. Journal of Nuclear Medicine Technology. 2007;35(4):213-225.
Habib-Geryes B, Hornbeck A, Jarrige V, Pierrat N, Ducou Le Pointe H, et al. Patient dose evaluation in computed tomography: A French national study based on clinical indications. Physica Medica. 2019;(61):18-27.
Feuchtner GM, Jodocy D, Klauser A. Radiation dose reduction by using 100 –KV tube voltage in cardiac 64 – slice computed tomography: A comparative study. Journal of Radiology. 2010;(75):51-56.
Bushong SC. Radiologic science for technologists St. Louis (3rded) Mosby. Elsevier; 2013.
Rafael C. How to calculate sample size using Taro Yamane’s formula; 2014. Available:https://www.nairaproject.com/blog/its-taro-yamane-not-yaro.html
Anam C, Haryanto F, Widita R, Arif I, Fujibuchi T, Dougherty G. A size-specific effective dose for patients undergoing CT examinations. J. Phys. Conf. Ser; 2019. DOI: 10.1088/1742-6596/1204/1/012002