Beam Production | Particle Accelerators
Both cyclotrons and synchrotrons are used in particle therapy, and each kind of accelerator has its advantages. The synchrotron offers the advantage of a variable energy, while the cyclotron operates at fixed energy and requires an energy selection system. But the beam current of synchrotrons, and therefore the dose rate for larger fields is limited.
In addition, for synchrotrons, the stability and controllability of the extracted beam is generally suboptimal, and does not allow high speed pencil beam scanning, with multiple repainting of each slice as done with the IBA cyclotron design. Only passive scattering and slower "stop and shoot" voxel scanning are possible with a synchrotron.
While it can be expected that the reputable manufacturers competing for a particle therapy system contract will offer accelerators of generally good quality, experience has shown that prototypes or early versions of a new design always require subsequent modifications due to design deficiencies.
All cyclotrons delivered by IBA today benefit from the experience of at least six of this series built before it, giving you confidence that it will not involve the immature design issues of near prototypes that may jeopardize the critical start-up phase of clinical operations.
Cyclotrons |
The choice of the accelerator, the source of beam production for your therapy center, is of paramount importance. It is a choice which must be made with your final goals in mind. For most oncology providers aiming to introduce particle therapy to their program, IBA recommends our fixed-energy isochronous cyclotron running at room temperature.
The goals of the accelerator are to equal the level of simplicity, reliability, operability and, as far as possible, the space requirements and cost of a radiation therapy electron linac. The accelerator chosen to achieve these goals is a fixed-energy, isochronous cyclotron, featuring a very high magnetic field to keep size, weight and cost at minimum while avoiding the use of superconducting coils.
230 MeV |
Simplicity, Maintainability
- The Proteus 235 from IBA is the simplest, most reliable, proven source of protons;
- Fixed parameters (only 7 are tunable);
- Room temperature cyclotron technology which allows for fast service and repair times;
- The Cyclotron yoke splits at the median plane for easy access to all components;
- Easy to maintain, easy to operate, inexpensive to service.
Accuracy
- Only cyclotrons allow accurate modulation of the proton beam current;
- Operates Continuous Wave.
- Continuous beam, allows fast beam regulation, better scattering & scanning dose regulation.
- Allows multiple paintings per layer in scanning mode.
Reliability
- Over 98% availability at Northeast Proton Therapy Center in Boston.
- High patient throughput, stress-free operations.
With the IBA cyclotron, you will have a precise and flexible Energy Selection System to continuously and efficiently tune the energy of the beam so that the beam energy is adapted exactly to the desired range in the patient.
400 MeV/u |
For those customers wishing to purchase from the outset an accelerator capable of supplying therapeutic beams of protons as well as heavy ions, IBA makes the 400 MeV/u superconducting cyclotron.
Some providers have expressed an interest in IBA’s novel two-phase approach – build two cyclotron vaults in the facility but install only the 230 MeV cyclotron initially. This way, from the time the contract is signed, the facility can begin treating patients within 3 years – gaining experience, expertise, and revenue. Assuming market development will include reimbursement and regulatory approval for heavy ions, the facility can later add the 400 MeV/u cyclotron, with revenues from proton therapy and minimal disruption to treatment and daily processes.
Synchrotrons |
A synchrotron is a ring based accelerator that accelerates the particles from a minimal energy to extraction energy. The extraction energy can be tuned to a set of fixed energy (today) and to a continuously adjustable energy (future).
The minimal energy required for the synchrotron to operate is generated thanks to an external ion source followed by a first accelerator called the injector.
The beam acceleration is the result of 4 steps happening one after the other.
- inject beam from the ion source and the injector into the synchrotron
- accelerate the beam inside the synchrotron
- extract the beam from the synchrotron
- bring the synchrotron to a state where it can accept injected beam
The time for those 4 operations is in the range of 3 seconds. As a consequence, the extracted beam is not continuous but pulsed at a rate of +/- 3 seconds.
IBA can also supply a synchrotron for customers so inclined, as the majority of our vast experience with particle acceleration also applies to building synchrotrons.
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