CT dose estimations using the ICRU/AAPM phantom





tomografia computadorizada, dosimetria, dose de equilíbrio, phantom


A proposed method to obtain the dose for Computed Tomography was evaluated on long a phantom, made of polyethylene. This phantom is 600 mm large. Adopting an empirical characterized function , a tendency of the asymptotical grow of the dose by the increase of the scanning length can estimate the dose in an infinite scanning length for a single axial rotation of the x-ray tube. The curve of  was estimated for different clinical protocols: tension, pitch, head/body, and center/peripheral measurements. The ultrahigh molecular weight polyethylene phantom of 600 mm length, named ICRU/AAPM phantom, was proposed by a partnership between ICRU and AAPM (Task Group 200). This length provides a higher scanner length then PMMA phantom for , whose measurement is 100 mm. The measures of ICRU/AAPM phantom were performed on General Electric, Toshiba, and Philips scanners. The measurement was performed on a thimble ion chamber inserted in the center or periphery of the phantom. Using the measurements,  functions (equilibrium dose, equilibrium length and scatter fraction) were obtained. A single scan has been demonstrated to be sufficient to obtain the  function.


Não há dados estatísticos.


Dixon RL. The Physics of CT Dosimetry: CTDI and Beyond. 1st ed. Boca Raton: CRC Press; 2019.

AAPM. The Measurement, Reporting, and Management of Radiation Dose in CT. American Association of Physicists in Medicine. 2008;AAPM Report 096.

Boone JM. The trouble with CTDI100. Medical Physics. 2007;34(4):1364-71.

AAPM. Comprehensive Methodology for the Evaluation of Radiation Dose in X-Ray Computed Tomography. American Association of Physicists in Medicine. 2010;AAPM Report 111.

ICRU. Radiation Dosimetry and Image Quality Assessment in Computed Tomography. International Commission on Radiation Units and Measurements. 2012;Report 87.

AAPM. The Design and Use of the ICRU/AAPM CT Radiation Dosimetry Phantom: An Implementation of AAPM Report 111. American Association of Physicists in Medicine. 2020;AAPM Report 200.

Costa PR, Nersissian DY, Umisedo NK, Gonzales AHL, Fernandez-Varea JM. A comprehensive Monte Carlo study of CT dose metrics proposed by the AAPM Reports 111 and 200. Medical Physics. 2022;49(1):201-18.

Dixon RL, Ballard AC. Experimental validation of a versatile system of CT dosimetry using a conventional ion chamber: beyond CTDI100. Medical physics. 2007;34(8).

Radcal Corporation. 10X6-0.6C: The Chamber for Computed Tomography Dose Index (CTDI); 2011.

Leitz W, Axelsson B, Szendro G. COMPUTED-TOMOGRAPHY DOSE ASSESSMENT - A PRACTICAL APPROACH. Radiation Protection Dosimetry. 1995;57(1-4):377-80.




Como Citar

Stefani, Y., Nersissian, D. Y., & Costa, P. R. (2022). CT dose estimations using the ICRU/AAPM phantom. Revista Brasileira De Física Médica, 16, 685. https://doi.org/10.29384/rbfm.2022.v16.19849001685



Artigo Original

Artigos mais lidos pelo mesmo(s) autor(es)