Department of Radiotherapy ❯ Our Techniques ❯ Tomotherapy
Tomotherapy is an advanced type of radiation therapy delivery system that combines image-guided and intensity-modulated radiation therapy (IGRT & IMRT), resulting in greater precision and accuracy in radiation treatment.
While conventional machines allow radiation to be delivered from only a few directions, the Tomotherapy treatment system continuously delivers radiation from all angles around the patient.
Radiation is produced by a device called the linear accelerator (linac). The linac is mounted to a CT scanner-like ring gantry in the Tomotherapy treatment machine. This unique ring gantry design enables the system to deliver radiation in a helical (continuous 360°) delivery pattern. It also uses a patented multi-leaf collimator (MLC) that divides the radiation beam into many smaller, narrow "beamlets". More angles and more beam modulation result in a more precise dose distribution. Meanwhile, the patient is lying on a couch which moves in and out of the machine, resulting in a dynamic, continuous treatment system.
Using powerful computer programs, radiation therapists create optimal plans for each individual patient which directs the radiation dose to the tumour while minimizing exposure to healthy tissue. The Tomotherapy system offers fast and precise stereotactic radiation therapy. The system allows us to achieve excellent dose conformality, even with highly irregular targets. In addition, Tomotherapy is able to treat multiple lesions in a single delivery sequence with a single setup. This offers a great advantage over other treatments using conventional linear accelerators which often require individual and/or separate treatments for multiple lesions.
The exact location of a tumour can vary every day depending on factors such as internal organ movement between treatments and the patient's relative position at the time of each treatment. This system allows us to take a CT scan just prior to each treatment in order to obtain a three-dimensional view of a patient's anatomy for that day.
By integrating these images with the planning CT images taken previously, we can adjust the patient's position to make sure radiation is directed right where it should be. The daily pre-treatment CT scan can also be used for dose guidance, allowing us to visualize the dose that will actually be delivered to the patient that day. This,often termed "adaptive radiation therapy", consists of clear analysis and precise adjustment of the treatment plan to account for changes over time. With the Tomotherapy treatment system, we offer highly precise and accurate radiation treatments to our patients, while reducing the risk of side effects and improving their quality of life.
This Technique provided by Radixact X9 TomoTherapy® System.