Clinical Pencil Beam Scanning: Present and Future Practices

  • Marco Schwarz
  • Carlo Algranati
  • Lamberto Widesott
  • Paolo Farace
  • Stefano Lorentini
  • Roberto Righetto
  • Daniele Ravanelli
  • Francesco Fracchiolla


Pencil beam scanning (PBS) is the most advanced beam delivery technology in particle therapy nowadays. After a pioneering phase, PBS is rapidly becoming available on a larger scale worlwide, and is expected to be the standard beam delivery technique in the future to come. The characterization of a PBS isocentric gantry involves a number of validation tests both at the hardware level (e.g. mechanical isocentricity of gantry and patient positioning system) and at the beam geometry level (e.g. spot size, shape and positional accuracy as a function of gantry angle and energy). A beam model is then generated in the treatment planning systems (TPS), and an extensive validation is needed, from simple geometries to heterogenous phantoms mimicking a patient. Last but not least, planning techniques ensuring plan robustness with respect to setup error and range uncertainties should be implemented in order to minimize the difference between planned and delivered dose distribution.


Planning Target Volume Dose Distribution Robust Optimization Treatment Planning System Proton Therapy 
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Copyright information

© Springer India 2016

Authors and Affiliations

  • Marco Schwarz
    • 1
  • Carlo Algranati
    • 1
  • Lamberto Widesott
    • 1
  • Paolo Farace
    • 1
  • Stefano Lorentini
    • 1
  • Roberto Righetto
    • 1
  • Daniele Ravanelli
    • 1
  • Francesco Fracchiolla
  1. 1.Protontherapy DepartmentTrento HospitalTrentoItaly

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