Energy- and intensity-modulated electron beams for radiotherapy

C. M. Ma, T. Pawlicki, M. C. Lee, S. B. Jiang, J. S. Li, J. Deng, B. Yi, E. Mok, A. L. Boyer

Research output: Contribution to journalArticle

81 Citations (Scopus)

Abstract

This work investigates the feasibility of optimizing energy- and intensity-modulated electron beams for radiation therapy. A multileaf collimator (MLC) specially designed for modulated electron radiotherapy (MERT) was investigated both experimentally and by Monte Carlo simulations. An inverse-planning system based on Monte Carlo dose calculations was developed to optimize electron beam energy and intensity to achieve dose conformity for target volumes near the surface. The results showed that an MLC with 5 mm leaf widths could produce complex field shapes for MERT. Electron intra- and inter-leaf leakage had negligible effects on the dose distributions delivered with the MLC, even at shallow depths. Focused leaf ends reduced the electron scattering contributions to the dose compared with straight leaf ends. As anticipated, moving the MLC position toward the patient surface reduced the penumbra significantly. There were significant differences in the beamlet distributions calculated by an analytic 3-D pencil beam algorithm and the Monte Carlo method. The Monte Carlo calculated beamlet distributions were essential to the accuracy of the MERT dose distribution in cases involving large air gaps, oblique incidence and heterogeneous treatment targets (at the tissue-bone and bone-lung interfaces). To demonstrate the potential of MERT for target dose coverage and normal tissue sparing for treatment of superficial targets, treatment plans for a hypothetical treatment were compared using photon beams and MERT.

Original languageEnglish (US)
Pages (from-to)2293-2311
Number of pages19
JournalPhysics in Medicine and Biology
Volume45
Issue number8
DOIs
StatePublished - 2000

Fingerprint

Radiotherapy
Electron beams
radiation therapy
leaves
electron beams
Electrons
collimators
dosage
electrons
bones
Dosimetry
energy
Bone
Tissue
pencil beams
penumbras
Electron scattering
photon beams
lungs
Monte Carlo method

ASJC Scopus subject areas

  • Biomedical Engineering
  • Physics and Astronomy (miscellaneous)
  • Radiology Nuclear Medicine and imaging
  • Radiological and Ultrasound Technology

Cite this

Ma, C. M., Pawlicki, T., Lee, M. C., Jiang, S. B., Li, J. S., Deng, J., ... Boyer, A. L. (2000). Energy- and intensity-modulated electron beams for radiotherapy. Physics in Medicine and Biology, 45(8), 2293-2311. https://doi.org/10.1088/0031-9155/45/8/316

Energy- and intensity-modulated electron beams for radiotherapy. / Ma, C. M.; Pawlicki, T.; Lee, M. C.; Jiang, S. B.; Li, J. S.; Deng, J.; Yi, B.; Mok, E.; Boyer, A. L.

In: Physics in Medicine and Biology, Vol. 45, No. 8, 2000, p. 2293-2311.

Research output: Contribution to journalArticle

Ma, CM, Pawlicki, T, Lee, MC, Jiang, SB, Li, JS, Deng, J, Yi, B, Mok, E & Boyer, AL 2000, 'Energy- and intensity-modulated electron beams for radiotherapy', Physics in Medicine and Biology, vol. 45, no. 8, pp. 2293-2311. https://doi.org/10.1088/0031-9155/45/8/316
Ma, C. M. ; Pawlicki, T. ; Lee, M. C. ; Jiang, S. B. ; Li, J. S. ; Deng, J. ; Yi, B. ; Mok, E. ; Boyer, A. L. / Energy- and intensity-modulated electron beams for radiotherapy. In: Physics in Medicine and Biology. 2000 ; Vol. 45, No. 8. pp. 2293-2311.
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