Pencil beam scanning is the practice of steering a beam of radiation or charged particles across an object. It is often used in proton therapy, to reduce unnecessary radiation exposure to surrounding non-cancerous cells.
Ionizing radiation
Ionizing radiation photons or x-rays (IMRT) use pencil beam scanning to precisely target a tumor. Photon pencil beam scans are defined as crossing of two beams to a fine point.
Charged particles
Several charged particles devices used with Proton therapy cancer centers use pencil beam scanning. The newer proton therapy machines use a pencil beam scanning technology. This technique is also called spot scanning. The Paul Scherrer Institute was the developer of spot beam.
Intensity Modulated Proton Therapy
Varian's IMPT system uses all pencil-beam controlled protons where the beam intensity can also be controlled at this small level. This can be done by going back and forth over a previously radiated area during the same radiation session.
See also
- Pencil (mathematics)
- Pencil (optics)
- Radiation treatment planning
- mean free path
- Monte Carlo method for photon transport
- Hybrid theory for photon transport in tissue
- Diffusion theory
- Monte Carlo method
- Varian Medical Systems
References
- Blake GM, Parker JC, Buxton FM, Fogelman I (October 1993). "Dual X-ray absorptiometry: a comparison between fan beam and pencil beam scans". Br J Radiol. 66 (790): 902–6. doi:10.1259/0007-1285-66-790-902. PMID 8220974.
- Khan, Faiz M. (2010). The Physics of Radiation Therapy. ISBN 9780781788564.
- http://www.accessdata.fda.gov/cdrh_docs/pdf10/K100766.pdf page4
- "03-30-09 - Advances in Proton Therapy, Pencil Beam Technology Reach Patient Care - MD Anderson Cancer Center". www.mdanderson.org. Archived from the original on 2011-03-03.
- "The PSI Proton Therapy Facility". radmed.web.psi.ch. Archived from the original on 2002-01-06.