Dataset Information

The ideal couch tracking system-Requirements and evaluation of current systems.

ABSTRACT:

Introduction

Intrafractional motion can cause substantial uncertainty in precision radiotherapy. Traditionally, the target volume is defined to be sufficiently large to cover the tumor in every position. With the robotic treatment couch, a real-time motion compensation can improve tumor coverage and organ at risk sparing. However, this approach poses additional requirements, which are systematically developed and which allow the ideal robotic couch to be specified.

Methods and materials

Data of intrafractional tumor motion were collected and analyzed regarding motion range, frequency, speed, and acceleration. Using this data, ideal couch requirements were formulated. The four robotic couches Protura, Perfect Pitch, RoboCouch, and RPSbase were tested with respect to these requirements.

Results

The data collected resulted in maximum speed requirements of 60 mm/s in all directions and maximum accelerations of 80 mm/s² in the longitudinal, 60 mm/s² in the lateral, and 30 mm/s² in the vertical direction. While the two robotic couches RoboCouch and RPSbase completely met the requirements, even these two showed a substantial residual motion (40% of input amplitude), arguably due to their time delays.

Conclusion

The requirements for the motion compensation by an ideal couch are formulated and found to be feasible for currently available robotic couches. However, the performance these couches can be improved further regarding the position control if the demanded speed and acceleration are taken into account as well.

SUBMITTER: Johl A

PROVIDER: S-EPMC6806475 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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Publications

The ideal couch tracking system-Requirements and evaluation of current systems.

Jöhl Alexander A Ehrbar Stefanie S Guckenberger Matthias M Klöck Stephan S Mack Andreas A Meboldt Mirko M Zeilinger Melanie M Tanadini-Lang Stephanie S Schmid Daners Marianne M

Journal of applied clinical medical physics 20190919 10

<h4>Introduction</h4>Intrafractional motion can cause substantial uncertainty in precision radiotherapy. Traditionally, the target volume is defined to be sufficiently large to cover the tumor in every position. With the robotic treatment couch, a real-time motion compensation can improve tumor coverage and organ at risk sparing. However, this approach poses additional requirements, which are systematically developed and which allow the ideal robotic couch to be specified.<h4>Methods and materia ...[more]

PMID: 31535782

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Dataset Information

The ideal couch tracking system-Requirements and evaluation of current systems.

Introduction

Methods and materials

Results

Conclusion

Publications

The ideal couch tracking system-Requirements and evaluation of current systems.

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