Realizing the Potential of the TomoTherapy® System
a 30-year History
A 30-year History
TomoTherapy® is a radiation therapy system that was originally developed by medical physicists of the University of Wisconsin in the late 1980s, as a novel concept to deliver dynamic helical radiotherapy, combined with image guidance. It is in a 1993 publication1 that Rock Mackie and team first proposed the innovative concept of TomoTherapy and gave this definition: “TomoTherapy, literally ‘slice therapy’, is a proposal for the delivery of radiation therapy with intensity modulated strips of radiation. […] The basic idea was to put a linear accelerator into a CT-like ring gantry configuration and deliver therapeutic radiation using a rotating fan beam which is modulated by a multi-leaved collimator system, while the patient moves through the gantry in the longitudinal direction. The system would use a tomographic imaging system for treatment verification, and tomographic reconstruction mathematics for optimal treatment planning.” “This method would result in the delivery of highly conformal radiation”, continued Rock Mackie.
The TomoTherapy concept emerged as a response to several major problems facing radiation therapy at the time, and answered several goals:
- Plan your delivery to maximize the dose to the tumor and to minimize the dose to neighboring sensitive structures.
- Ensure that you deliver the dose volume where you plan to — by using daily, fully integrated 3D image guidance capabilities.
- Avoid collisions of systems and patient — with a safer design based on CT-like ring gantry.
The history of helical TomoTherapy is a story of technology migration from academic research, with a university — industry partnership, to commercialization and widespread clinical use. In 1997, TomoTherapy Incorporated was created by the researchers working on the project. The TomoTherapy system went through a long process of prototype development and optimization. The first prototype was achieved in early 2001 at the University of Wisconsin Medical Centre. In August 2002, the first patient was treated by Jim Welsh at the University of Wisconsin on the first TomoTherapy® system.2
- Mackie TR, Holmes T, Swerdloff S, Reckwerdt P, Deasy JO, Yang J, Paliwal B, Kinsella T. TomoTherapy: a new concept for the delivery of dynamic conformal radiotherapy. Med Phys 1993; 20(6):1709-19.
- Mackie TR. History of TomoTherapy. Phys Med Biol 2006; 51(13):R427-53.
