liu.seSearch for publications in DiVA
Change search
ReferencesLink to record
Permanent link

Direct link
Optimization of the computational efficiency of a 3D, collapsed cone dose calculation algorithm for brachytherapy.
Linköping University, Department of Medicine and Health Sciences, Radiation Physics . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Radiation Physics.
Uppsala University.
2008 (English)In: Medical physics (Lancaster), ISSN 0094-2405, Vol. 35, no 4, 1611-1618 p.Article in journal (Refereed) Published
Abstract [en]

Brachytherapy dose calculations based on point kernel superposition using the collapsed cone method have been shown to accurately model the influence from finite dimensions of the patient and effects from heterogeneities including those of high atomic numbers. The collapsed cone method is for brachytherapy applications most effectively implemented through a successive-scattering approach, in which the dose from once and higher order of scattered photons is calculated separately and in successive scatter order. The calculation speed achievable is directly proportional to the number of directions used for point kernel discretization and to the number of voxels in the volume. In this work we investigate how to best divide the total number of directions between the two steps of successive-scattering dose calculations. Results show that the largest fraction of the total number of directions should be utilized in calculating the first-scatter dose. Also shown is how the number of directions required for keeping discretization artifacts at acceptably low levels decreases significantly in multiple-source configurations, as a result of the dose gradients being less steep than those around single sources. Investigating the number of kernel directions required to keep artifacts low enough within the high dose region of an implant (i.e., for dose levels above approximately 5%-10% of the mean central target dose) reveals similar figures for brachytherapy as for external beam applications, where collapsed cone superposition is clinically used. Also shown is that approximating point kernels with their isotropic average leads to small dose differences at low and intermediate energies, implying that the collapsed cone calculations can be done in a single operation common to all sources of the implant at these energies. The current findings show that collapsed cone calculations can be achieved for brachytherapy with the same efficiency as for external beams. This, combined with recent results on gains in efficiency through implementing the algorithm on graphical card parallel hardware indicates that dose can be calculated with account for heterogeneities and finite dimensions within a few seconds for large voxel arrays and is therefore of interest for practical application to treatment planning.

Place, publisher, year, edition, pages
2008. Vol. 35, no 4, 1611-1618 p.
Keyword [en]
brachytherapy, dose calculation, heterogeneities, collapsed cone, Monte Carlo
National Category
Medical and Health Sciences
URN: urn:nbn:se:liu:diva-19574DOI: 10.1118/1.2889777OAI: diva2:225493
Original Publication: Asa Carlsson Tedgren and Anders Ahnesjö, Optimization of the computational efficiency of a 3D, collapsed cone dose calculation algorithm for brachytherapy., 2008, Medical physics (Lancaster), (35), 4, 1611-1618. Copyright: American Institute of Physics Available from: 2009-07-03 Created: 2009-06-29 Last updated: 2009-08-17Bibliographically approved

Open Access in DiVA

fulltext(1059 kB)464 downloads
File information
File name FULLTEXT01.pdfFile size 1059 kBChecksum SHA-512
Type fulltextMimetype application/pdf

Other links

Publisher's full text

Search in DiVA

By author/editor
Carlsson Tedgren, Asa
By organisation
Radiation Physics Faculty of Health SciencesDepartment of Radiation Physics
In the same journal
Medical physics (Lancaster)
Medical and Health Sciences

Search outside of DiVA

GoogleGoogle Scholar
Total: 464 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 131 hits
ReferencesLink to record
Permanent link

Direct link