Monte Carlo simulations to assess the effects of tube current modulation on breast dose for multidetector CT

Erin Angel, Nazanin Yaghmai, Cecilia Matilda Jude, John J. Demarco, Christopher H. Cagnon, Jonathan G. Goldin, Andrew N. Primak, Donna M. Stevens, Dianna D. Cody, Cynthia H McCollough, Michael F. McNitt-Gray

Research output: Contribution to journalArticle

59 Citations (Scopus)

Abstract

Tube current modulation was designed to reduce radiation dose in CT imaging while maintaining overall image quality. This study aims to develop a method for evaluating the effects of tube current modulation (TCM) on organ dose in CT exams of actual patient anatomy. This method was validated by simulating a TCM and a fixed tube current chest CT exam on 30 voxelized patient models and estimating the radiation dose to each patient's glandular breast tissue. This new method for estimating organ dose was compared with other conventional estimates of dose reduction. Thirty detailed voxelized models of patient anatomy were created based on image data from female patients who had previously undergone clinically indicated CT scans including the chest area. As an indicator of patient size, the perimeter of the patient was measured on the image containing at least one nipple using a semi-automated technique. The breasts were contoured on each image set by a radiologist and glandular tissue was semi-automatically segmented from this region. Previously validated Monte Carlo models of two multidetector CT scanners were used, taking into account details about the source spectra, filtration, collimation and geometry of the scanner. TCM data were obtained from each patient's clinical scan and factored into the model to simulate the effects of TCM. For each patient model, two exams were simulated: a fixed tube current chest CT and a tube current modulated chest CT. X-ray photons were transported through the anatomy of the voxelized patient models, and radiation dose was tallied in the glandular breast tissue. The resulting doses from the tube current modulated simulations were compared to the results obtained from simulations performed using a fixed mA value. The average radiation dose to the glandular breast tissue from a fixed tube current scan across all patient models was 19 mGy. The average reduction in breast dose using the tube current modulated scan was 17%. Results were size dependent with smaller patients getting better dose reduction (up to 64% reduction) and larger patients getting a smaller reduction, and in some cases the dose actually increased when using tube current modulation (up to 41% increase). The results indicate that radiation dose to glandular breast tissue generally decreases with the use of tube current modulated CT acquisition, but that patient size (and in some cases patient positioning) may affect dose reduction.

Original languageEnglish (US)
Pages (from-to)497-511
Number of pages15
JournalPhysics in Medicine and Biology
Volume54
Issue number3
DOIs
StatePublished - 2009

Fingerprint

Breast
Radiation
Chest Tubes
Anatomy
Thorax
Patient Positioning
Nipples
Photons
X-Rays

ASJC Scopus subject areas

  • Radiology Nuclear Medicine and imaging
  • Radiological and Ultrasound Technology

Cite this

Angel, E., Yaghmai, N., Jude, C. M., Demarco, J. J., Cagnon, C. H., Goldin, J. G., ... McNitt-Gray, M. F. (2009). Monte Carlo simulations to assess the effects of tube current modulation on breast dose for multidetector CT. Physics in Medicine and Biology, 54(3), 497-511. https://doi.org/10.1088/0031-9155/54/3/003

Monte Carlo simulations to assess the effects of tube current modulation on breast dose for multidetector CT. / Angel, Erin; Yaghmai, Nazanin; Jude, Cecilia Matilda; Demarco, John J.; Cagnon, Christopher H.; Goldin, Jonathan G.; Primak, Andrew N.; Stevens, Donna M.; Cody, Dianna D.; McCollough, Cynthia H; McNitt-Gray, Michael F.

In: Physics in Medicine and Biology, Vol. 54, No. 3, 2009, p. 497-511.

Research output: Contribution to journalArticle

Angel, E, Yaghmai, N, Jude, CM, Demarco, JJ, Cagnon, CH, Goldin, JG, Primak, AN, Stevens, DM, Cody, DD, McCollough, CH & McNitt-Gray, MF 2009, 'Monte Carlo simulations to assess the effects of tube current modulation on breast dose for multidetector CT', Physics in Medicine and Biology, vol. 54, no. 3, pp. 497-511. https://doi.org/10.1088/0031-9155/54/3/003
Angel, Erin ; Yaghmai, Nazanin ; Jude, Cecilia Matilda ; Demarco, John J. ; Cagnon, Christopher H. ; Goldin, Jonathan G. ; Primak, Andrew N. ; Stevens, Donna M. ; Cody, Dianna D. ; McCollough, Cynthia H ; McNitt-Gray, Michael F. / Monte Carlo simulations to assess the effects of tube current modulation on breast dose for multidetector CT. In: Physics in Medicine and Biology. 2009 ; Vol. 54, No. 3. pp. 497-511.
@article{3bf376a0fe684d1a9b652ac919d9eb48,
title = "Monte Carlo simulations to assess the effects of tube current modulation on breast dose for multidetector CT",
abstract = "Tube current modulation was designed to reduce radiation dose in CT imaging while maintaining overall image quality. This study aims to develop a method for evaluating the effects of tube current modulation (TCM) on organ dose in CT exams of actual patient anatomy. This method was validated by simulating a TCM and a fixed tube current chest CT exam on 30 voxelized patient models and estimating the radiation dose to each patient's glandular breast tissue. This new method for estimating organ dose was compared with other conventional estimates of dose reduction. Thirty detailed voxelized models of patient anatomy were created based on image data from female patients who had previously undergone clinically indicated CT scans including the chest area. As an indicator of patient size, the perimeter of the patient was measured on the image containing at least one nipple using a semi-automated technique. The breasts were contoured on each image set by a radiologist and glandular tissue was semi-automatically segmented from this region. Previously validated Monte Carlo models of two multidetector CT scanners were used, taking into account details about the source spectra, filtration, collimation and geometry of the scanner. TCM data were obtained from each patient's clinical scan and factored into the model to simulate the effects of TCM. For each patient model, two exams were simulated: a fixed tube current chest CT and a tube current modulated chest CT. X-ray photons were transported through the anatomy of the voxelized patient models, and radiation dose was tallied in the glandular breast tissue. The resulting doses from the tube current modulated simulations were compared to the results obtained from simulations performed using a fixed mA value. The average radiation dose to the glandular breast tissue from a fixed tube current scan across all patient models was 19 mGy. The average reduction in breast dose using the tube current modulated scan was 17{\%}. Results were size dependent with smaller patients getting better dose reduction (up to 64{\%} reduction) and larger patients getting a smaller reduction, and in some cases the dose actually increased when using tube current modulation (up to 41{\%} increase). The results indicate that radiation dose to glandular breast tissue generally decreases with the use of tube current modulated CT acquisition, but that patient size (and in some cases patient positioning) may affect dose reduction.",
author = "Erin Angel and Nazanin Yaghmai and Jude, {Cecilia Matilda} and Demarco, {John J.} and Cagnon, {Christopher H.} and Goldin, {Jonathan G.} and Primak, {Andrew N.} and Stevens, {Donna M.} and Cody, {Dianna D.} and McCollough, {Cynthia H} and McNitt-Gray, {Michael F.}",
year = "2009",
doi = "10.1088/0031-9155/54/3/003",
language = "English (US)",
volume = "54",
pages = "497--511",
journal = "Physics in Medicine and Biology",
issn = "0031-9155",
publisher = "IOP Publishing Ltd.",
number = "3",

}

TY - JOUR

T1 - Monte Carlo simulations to assess the effects of tube current modulation on breast dose for multidetector CT

AU - Angel, Erin

AU - Yaghmai, Nazanin

AU - Jude, Cecilia Matilda

AU - Demarco, John J.

AU - Cagnon, Christopher H.

AU - Goldin, Jonathan G.

AU - Primak, Andrew N.

AU - Stevens, Donna M.

AU - Cody, Dianna D.

AU - McCollough, Cynthia H

AU - McNitt-Gray, Michael F.

PY - 2009

Y1 - 2009

N2 - Tube current modulation was designed to reduce radiation dose in CT imaging while maintaining overall image quality. This study aims to develop a method for evaluating the effects of tube current modulation (TCM) on organ dose in CT exams of actual patient anatomy. This method was validated by simulating a TCM and a fixed tube current chest CT exam on 30 voxelized patient models and estimating the radiation dose to each patient's glandular breast tissue. This new method for estimating organ dose was compared with other conventional estimates of dose reduction. Thirty detailed voxelized models of patient anatomy were created based on image data from female patients who had previously undergone clinically indicated CT scans including the chest area. As an indicator of patient size, the perimeter of the patient was measured on the image containing at least one nipple using a semi-automated technique. The breasts were contoured on each image set by a radiologist and glandular tissue was semi-automatically segmented from this region. Previously validated Monte Carlo models of two multidetector CT scanners were used, taking into account details about the source spectra, filtration, collimation and geometry of the scanner. TCM data were obtained from each patient's clinical scan and factored into the model to simulate the effects of TCM. For each patient model, two exams were simulated: a fixed tube current chest CT and a tube current modulated chest CT. X-ray photons were transported through the anatomy of the voxelized patient models, and radiation dose was tallied in the glandular breast tissue. The resulting doses from the tube current modulated simulations were compared to the results obtained from simulations performed using a fixed mA value. The average radiation dose to the glandular breast tissue from a fixed tube current scan across all patient models was 19 mGy. The average reduction in breast dose using the tube current modulated scan was 17%. Results were size dependent with smaller patients getting better dose reduction (up to 64% reduction) and larger patients getting a smaller reduction, and in some cases the dose actually increased when using tube current modulation (up to 41% increase). The results indicate that radiation dose to glandular breast tissue generally decreases with the use of tube current modulated CT acquisition, but that patient size (and in some cases patient positioning) may affect dose reduction.

AB - Tube current modulation was designed to reduce radiation dose in CT imaging while maintaining overall image quality. This study aims to develop a method for evaluating the effects of tube current modulation (TCM) on organ dose in CT exams of actual patient anatomy. This method was validated by simulating a TCM and a fixed tube current chest CT exam on 30 voxelized patient models and estimating the radiation dose to each patient's glandular breast tissue. This new method for estimating organ dose was compared with other conventional estimates of dose reduction. Thirty detailed voxelized models of patient anatomy were created based on image data from female patients who had previously undergone clinically indicated CT scans including the chest area. As an indicator of patient size, the perimeter of the patient was measured on the image containing at least one nipple using a semi-automated technique. The breasts were contoured on each image set by a radiologist and glandular tissue was semi-automatically segmented from this region. Previously validated Monte Carlo models of two multidetector CT scanners were used, taking into account details about the source spectra, filtration, collimation and geometry of the scanner. TCM data were obtained from each patient's clinical scan and factored into the model to simulate the effects of TCM. For each patient model, two exams were simulated: a fixed tube current chest CT and a tube current modulated chest CT. X-ray photons were transported through the anatomy of the voxelized patient models, and radiation dose was tallied in the glandular breast tissue. The resulting doses from the tube current modulated simulations were compared to the results obtained from simulations performed using a fixed mA value. The average radiation dose to the glandular breast tissue from a fixed tube current scan across all patient models was 19 mGy. The average reduction in breast dose using the tube current modulated scan was 17%. Results were size dependent with smaller patients getting better dose reduction (up to 64% reduction) and larger patients getting a smaller reduction, and in some cases the dose actually increased when using tube current modulation (up to 41% increase). The results indicate that radiation dose to glandular breast tissue generally decreases with the use of tube current modulated CT acquisition, but that patient size (and in some cases patient positioning) may affect dose reduction.

UR - http://www.scopus.com/inward/record.url?scp=63649162415&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=63649162415&partnerID=8YFLogxK

U2 - 10.1088/0031-9155/54/3/003

DO - 10.1088/0031-9155/54/3/003

M3 - Article

VL - 54

SP - 497

EP - 511

JO - Physics in Medicine and Biology

JF - Physics in Medicine and Biology

SN - 0031-9155

IS - 3

ER -