Correlation between CT numbers and tissue parameters needed for Monte Carlo simulations of clinical dose distributions
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We describe a new method to convert CT numbers into mass density and elemental weights of tissues required as input for dose calculations with Monte Carlo codes such as EGS4. As a first step, we calculate the CT numbers for 71 human tissues. To reduce the effort for the necessary fits of the CT numbers to mass density and elemental weights, we establish four sections on the CT number scale, each confined by selected tissues. Within each section, the mass density and elemental weights of the selected tissues are interpolated. For this purpose, functional relationships between the CT number and each of the tissue parameters, valid for media which are composed of only two components in varying proportions, are derived. Compared with conventional data fits, no loss of accuracy is accepted when using the interpolation functions. Assuming plausible values for the deviations of calculated and measured CT numbers, the mass density can be determined with an accuracy better than 0.04 g cm(-3). The weights of phosphorus and calcium can be determined with maximum uncertainties of 1 or 2.3 percentage points (pp) respectively. Similar values can be achieved for hydrogen (0.8 pp) and nitrogen (3 pp). For carbon and oxygen weights, errors up to 14 pp can occur. The influence of the elemental weights on the results of Monte Carlo dose calculations is investigated and discussed.
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Material decomposition by thresholding works well for large HU discrepancies but may fail between soft tissue and bone in presence of low mineral density.
“This works well for large HU discrepancies, e. g. air ([ -1000] HU) and bone ([200 , 3000] HU), but may fail otherwise, particularly between soft tissue ([ -150 , 300] HU) and bone in presence of low mineral density.”
From DeepDRR – A Catalyst for Machine Learning in Fluoroscopy-Guided Procedures (2018) · cites this paper as [12]
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Cites
Principles of Computerized Tomographic Imaging
Kak, A. C., & Slaney, M. (2001) · doi:10.1137/1.9780898719277 · Cited by 5,809 · see citing works
The calibration of CT Hounsfield units for radiotherapy treatment planning
Schneider, U., Pedroni, E. S., & Lomax, A. (1996) · Physics in Medicine and Biology · doi:10.1088/0031-9155/41/1/009 · Cited by 1,100 · see citing works
The composition of body tissues
WOODARD, H. Q., & White, D. R. (1986) · British Journal of Radiology · doi:10.1259/0007-1285-59-708-1209 · Cited by 769 · see citing works
Electron beam dose calculations
Hogstrom, K. R., Mills, M. D., & Almond, P. R. (1981) · Physics in Medicine and Biology · doi:10.1088/0031-9155/26/3/008 · Cited by 355 · see citing works
3D electron dose calculation using a Voxel based Monte Carlo algorithm (VMC)
Kawrakow, I., Fippel, M., & Friedrich, K. (1996) · Medical Physics · doi:10.1118/1.597673 · Cited by 323 · see citing works
Measurement of effective atomic number and electron density using an EMI scanner
Rutherford, R. A., Pullan, B. R., & Isherwood, I. (1976) · Neuroradiology · doi:10.1007/bf00327253 · Cited by 300 · see citing works
Photon attenuation in computed tomography
McCullough, E. C. (1975) · Medical Physics · doi:10.1118/1.594199 · Cited by 290 · see citing works
Average soft-tissue and bone models for use in radiation dosimetry
White, D. R., WOODARD, H. Q., & Hammond, S. M. (1987) · British Journal of Radiology · doi:10.1259/0007-1285-60-717-907 · Cited by 242 · see citing works
A CT‐based Monte Carlo simulation tool for dosimetry planning and analysis
DeMarco, J. J., Solberg, T. D., & Smathers, J. B. (1998) · Medical Physics · doi:10.1118/1.598167 · Cited by 213 · see citing works
An electron density calibration phantom for CT-based treatment planning computers
Constantinou, C., Harrington, J. C., & DeWerd, L. A. (1992) · Medical Physics · doi:10.1118/1.596862 · Cited by 187 · see citing works
A patient‐specific Monte Carlo dose‐calculation method for photon beams
Wang, L., Chui, C., & Lovelock, M. (1998) · Medical Physics · doi:10.1118/1.598262 · Cited by 125 · see citing works
The storage and manipulation of radiation dose data in a small digital computer
Milan, J., & Bentley, R. E. T. (1974) · British Journal of Radiology · doi:10.1259/0007-1285-47-554-115 · Cited by 109 · see citing works
The direct use of CT numbers in radiotherapy dosage calculations for inhomogeneous media
Parker, R. P., Hobday, P., & Cassell, K. J. (1979) · Physics in Medicine and Biology · doi:10.1088/0031-9155/24/4/011 · Cited by 101 · see citing works
du Plessis, F. C. P., Willemse, C. A., Lötter, M. G., et al. (1998) · Medical Physics · doi:10.1118/1.598297 · Cited by 72 · see citing works
Bone models for use in radiotherapy dosimetry
WOODARD, H. Q., & White, D. R. (1982) · British Journal of Radiology · doi:10.1259/0007-1285-55-652-277 · Cited by 56 · see citing works
Lawrence Livermore National Laboratory`s PEREGRINE project
Hartmann-Siantar, C., Bergstrom, P. M., & Chandler, W. P. (1997) · University of North Texas Digital Library (University of North Texas) · Cited by 35 · see citing works
The use of computed tomography data for radiotherapy dose calculations
Kijewski, P. K., & Bjärngard, B. E. (1978) · International Journal of Radiation Oncology*Biology*Physics · doi:10.1016/0360-3016(78)90073-1 · Cited by 33 · see citing works
Gao, W., & Raeside, D. E. (1997) · Physics in Medicine and Biology · doi:10.1088/0031-9155/42/12/009 · Cited by 24 · see citing works
The electron density of bone for inhomogeneity correction in radiotherapy planning using CT numbers
Henson, P. W., & Fox, R. (1984) · Physics in Medicine and Biology · doi:10.1088/0031-9155/29/4/005 · Cited by 24 · see citing works
Monte Carlo simulation of dose distribution in electron beam radiotherapy treatment planning
Manfredotti, C., Nastasi, U., Marchisio, R., et al. (1990) · Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment · doi:10.1016/0168-9002(90)90015-x · Cited by 19 · see citing works
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DeepDRR – A Catalyst for Machine Learning in Fluoroscopy-Guided Procedures
Unberath, M., Zaech, J.-N., Lee, S. C., Bier, B., Fotouhi, J., Armand, M., & Navab, N. (2018) · Lecture Notes in Computer Science · doi:10.1007/978-3-030-00937-3_12 · Cited by 145 · see citing works
Kainz, W., Neufeld, E., Bolch, W. E., Graff, C. G., Kim, C. H., Kuster, N., Lloyd, B., Morrison, T., Segars, P., Yeom, Y. S., et al. (2019) · IEEE Transactions on Radiation and Plasma Medical Sciences · doi:10.1109/trpms.2018.2883437 · Cited by 109 · see citing works
- Authors
- Schneider, W., Bortfeld, T., & Schlegel, W.
- Affiliations
- German Cancer Research Center (DE)
- ORCID
- Bortfeld, Thomas
- Venue
- Physics in Medicine and Biology
- Publisher
- IOP Publishing
- Published
- 2000-01-25
- Volume
- 45
- Issue
- 2
- Pages
- 459-478
- ISSN
- 0031-9155 (ISSN-L)
- 1361-6560
- OpenAlex
- W2045415729
- Cited by
- 831
- References
- 20
- Citations by year
- 2026: 37 · 2025: 59 · 2024: 41 · 2023: 57 · 2022: 58 · 2021: 40 · 2020: 49 · 2019: 39 · 2018: 63 · 2017: 45 · 2016: 47 · 2015: 54 · 2014: 26 · 2013: 53 · 2012: 27
- FWCI
- 2.85
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Locations
- Physics in Medicine and Biology (publishedVersion)
- PubMed (publishedVersion)
- Topics
- Physical Sciences › Physics and Astronomy › Radiation › Advanced Radiotherapy Techniques
- Physical Sciences › Physics and Astronomy › Radiation › Radiation Therapy and Dosimetry
- Health Sciences › Medicine › Radiology, Nuclear Medicine and Imaging › Radiation Dose and Imaging
- Keywords
- Hounsfield units, elemental composition, Monte Carlo dose calculation, EGS4, interpolation functions, human tissue, phosphorus, calcium, radiotherapy dose distribution
- MeSH terms
- Female, Humans, Image Processing, Computer-Assisted, Male, Monte Carlo Method, Organ Specificity, Radiotherapy Planning, Computer-Assisted, Tomography, X-Ray Computed, Phantoms, Imaging
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