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Gamma Knife radiosurgery: Scenarios and support for re-irradiation

Published:November 21, 2019DOI:https://doi.org/10.1016/j.ejmp.2019.11.001

      Highlights

      • Re-irradiation spans a range of repeat-treatment and mixed-treatment modality scenarios.
      • Re-irradiation involving SRS is becoming more common.
      • Minimizing treatment uncertainty is critical for SRS in re-irradiation situations.
      • Multi-session GKRS supports many re-irradiation situations.
      • The GKRS platform design works to minimize beam-delivery uncertainties.

      Abstract

      Stereotactic radiosurgery (SRS) involves the focal delivery of large, cytotoxic doses of radiation to small targets within the brain, often located in close proximity to radiosensitive normal tissue structures and requiring very low procedural uncertainties to perform safely. Historically, neurosurgeons considered SRS as a one-time, single session procedure. However therapeutic advances and a better understanding of the clinical response to SRS have caused a renewal of interest in a variety of re-irradiation scenarios; including re-irradiation of the same target after prior SRS, SRS treatments after prior broad-field radiation, hypofractionated treatments, and volume-staged treatments. Re-irradiation may in some cases require even greater effort towards minimizing treatment uncertainties as compared to one-time-only treatments. Gamma Knife radiosurgery (GKRS) has evolved over time in ways that directly supports many re-irradiation scenarios while helping to minimize overall procedural uncertainty.

      Keywords

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