Related Links
- Stereotactic radiosurgery, 1995 (AAPM)
- Radiation Oncology Physics: A Handbook for Teachers and Students 2005 (IAEA), Ch.15.2 Stereotactic irradiation
- Practice Guideline for the Performance of Stereotactic Body Radiation Therapy, 2009 (ACR)
- Meyer J.L., Kavanagh B.D. (2007). IMRT, IGRT, SBRT: Advances in the Treatment Planning and Delivery of Radiotherapy. S Karger: Basel, Switzerland. ISBN 9783805581998 - In particular Ch.16 "Stereotactic Irradiation"
- Mayles P., Nahum A., Rosenwald J.C. (2007). Handbook of Radiotherapy Physics: Theory and Practice. CRC Press: Boca Raton, FL. ISBN 9780750308601
- Van Dyk, J. (1999). The Modern Technology of Radiation Oncology: A Compendium for Medical Physicists and Radiation Oncologists. Medical Physics Publishing: Madison WI ISBN 9780944838389
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Stereotactic radiation therapy (SRT)
Introduction
SRT comprises high-precision irradiation techniques that use multiple, non-coplanar photon radiation beams, and deliver a high dose of radiation to stereotactically localized lesions, applying frame-based and frameless techniques. These lesions were originally mainly located in the brain, but now also include a number of extra-cranial malignancies. With regard to dose fractionation, SRT is divided into stereotactic radiosurgery, in which the total dose is delivered in a single treatment session, and stereotactic radiotherapy, in which the total dose is delivered in multiple fractions, similar to standard radiotherapy.
Important Principles
SRT can be given using a wide variety of treatment devices and may incorporate specialized dose delivery methods such as IMRT. Requirements for SRT comprise secure patient immobilization, accurate tumour relocalization, and a solution for respiratory motion, if relevant. Dedicated SRT equipment is now commercially available and includes the GammaKnife, which incorporates 201 cobalt-60 sources, linacs that combine IGRT with modern immobilization and respiratory motion technology, and the CyberKnife, which incorporates a miniature linac mounted on a robotic arm. All steps involved in SRT must be verified experimentally to ensure reliable and accurate performance of the hardware and software. The most important requirement of a linac used for SRT is the mechanical stability and accuracy of its isocentre. In SRT dose conformity to a relatively small target volume is extremely important, and the target dose homogeneity requirement is often relaxed to allow for optimization of the target dose conformity.
Introduction to References
The various aspects of the early types of stereotactic radiosurgery, including requirements for a QA programme, were summarised in the initial
AAPM Report. More recent developments in the field of SRT can be found in J. Van Dyk's Compendium, the
IAEA Handbook, and the Handbook of Radiotherapy Physics. A comprehensive discussion of both physical and clinical aspects of SRT is provided in the book edited by Meyer. In 2009, the American College Radiology developed some practice
guidelines in Stereotactic Body Radiotherapy.
