Proton Therapy Equipment Installation, Upgrades, and Building Design

Abstract

This work aims at reviewing challenges and pitfalls in proton facility design related to equipment upgrade or replacement. Proton therapy was initially developed at research institutions in the 1950s which ushered in the use of hospital-based machines in 1990s. We are approaching an era where older commercial machines are reaching the end of their life and require replacement. The future widespread application of proton therapy depends on cost reduction; customized building design and installation are significant expenses. We take this opportunity to discuss how commercial proton machines have been installed and how buildings housing the equipment have been designed. Data on dimensions and weights of the larger components of proton systems (cyclotron main magnet and gantries) are presented and innovative, nongantry-based, patient positioning systems are discussed. We argue that careful consideration of the building design to include larger elevators, hoistways from above, wide corridors and access slopes to below grade installations, generic vault and treatment room layouts to accommodate multiple vendor's equipment, and modular system design can provide specific benefits during planning, installation, maintenance, and replacement phases of the project. Room temperature magnet coils can be constructed in a more modular manner: potential configurations are presented. There is scope for constructing gantries and magnet yokes from smaller modular sub-units. These considerations would allow a hospital to replace a commercial machine at its end of life in a manner similar to a linac.