Radiation therapy: linear accelerator Elekta Synergy Platform for IMRT- and IGRT
Radiation therapy in the Spizhenko Clinic is performed on the latest generation linear accelerator Elekta Synergy Platform, which works on the principle of IMRT (intensity-modulated radiation therapy), which protects normal tissues outside of the target volume from radiation during treatment with constant monitoring of the accuracy of the dose (IGRT).
Elekta Synergy is the first linear accelerator with the 3D visualization system which is embedded in the treatment process (Image guided radiotherapy – IGRT). The system is equipped with visualization tools that help the doctor to set out accurately the contours of the tumor and the healthy tissues, and, moreover, take into account their possible movements during fractions and between them. Integration of this technology into the moving part of the linear accelerator Elekta Synergy makes it possible to optimize the position of the patient before the start of therapy.
IMRT (Intensity modulated radiotherapy) is a modern method of radiotherapy, which aims is minimizing the dose to surrounding normal tissue adjacent to the tumor, but in which the tumor itself receives the maximum necessary dose of radiation — thereby increasing the total effective dose of treatment. Therefore, IMRT allows performing treatment for a relatively smaller number of sessions, which means shortening the therapy time.
The main advantages of IMRT in comparison with conventional radiation therapy:
- maximum protection of the healthy tissues and organs;
- high effective dose of tumor irradiation;
- the ability to treat complex (in size and form) tumors;
- reduced exposure time.
Radiation therapy is one of the leading methods of oncological deseases treatment, based on the increased sensitivity of cancer tumors to ionizing radiation, produced by the linear accelerator. Cancer cells die after the action of radiation from the linear accelerator and then normal cells of the body, adjacent to the tumor, resume their function.
The radiotherapy (IMRT) cost in the Clinic is comparable to the radiotherapy cost offered in other specialized clinics in Ukraine. However, unlike older models of linear accelerators, which, due to a simplified design, irradiate a large area of the body of the certain shape (circle or square), our linear accelerator Elekta Synergy allows to deliver the required dose accurately to the boundaries of a tumor even with irregular shape, excluding damage the healthy tissues. This accuracy is provided by a multi-petal collimator, under the control of the computer which outline the tumor by the «tracing» beam of radiation. Thus, a patient receives from 80 to 100 minimal irradiation fractions during one session of IMRT radiotherapy with a total dose lower then with 4-6 powerful fractions of a conventional linear accelerator.
At the same time, IMRT radiotherapy technology protects the healthy tissues around the tumor by exposing them by small doses of radiation, while a more effective dose is applied to the tumor itself. This helps to eliminate the recurrence inherent in conventional linear therapy (tumor re-development due to insufficient irradiation).
Benefits of linear accelerator
- A careful topometric preparation is performed by using CT and MRI scans for a precise determination of the location and size of the tumor, as well as a study of the condition of surrounding the healthy tissues.
- An individual voluminous planning is carried out with the selection of optimal doses for the tumor and the reduction of the radiation exposure on the healthy tissues adjacent to the tumor.
- The latest technological advances of the linear accelerator allow to implement the accurate planning and safety: a multileaf collimator allows configuring the tumor irradiation field of various complex shapes, providing reliable protection of all surrounding tissues.
- The implementation of accurate dose management is carried out by using a special device (portal vision) that monitors the tumor position before the start of the treatment.
- Immobility and comfort of the patient is provided by fixing devices (thermoplastic masks and vacuum mattresses) during the treatment.
- The video surveillance system allows a patient to keep in touch with a doctor during the treatment session.
- Treatment with a help of linear accelerator is well tolerated by patients and is performed on an outpatient basis.
Linear accelerator is used:
|Brain tumors|| |
|Head and Neck Cancers|| |
|Spinal cord tumor|| |
|Spinal cord tumor|| |
|Breast tumor|| |
|Gastrointestinal cancer|| |
|Genitourinary tract tumours|| |
|Bones, joints, and soft tissue tumors|| |
|Skin tumors|| |
How the linear accelerator treats
Cancer cells are sensitive to ionizing radiation, which produces a linear accelerator. Irradiated cells mutate and quickly die. Healthy cells are much more resistant to this kind of radiation, so they are able to survive under such fatal changes. Healthy cells are much more resistant to this kind of radiation, so they are able to survive under such fatal changes.
The linear accelerator Elekta Synergy creates a high energy photons or electrons, which are sent to the exact location of the tumor. Photon radiation is used when a tumor is in a difficult position to treat while electrons are used to treat tumors located close to the skin.
The planning of treatment on a linear accelerator allows the development of an individual program for each patient: to vary the energy of the beam, the configuration and the number of irradiation fields, the single and total focal dose, the position of the patient during the session. Multi-leaf collimators of the accelerator distributes the beams (each collimator leaf can move independently under computer control) in such a way to shield organs at risk whilst allowing the complex shape of the tumor bed to be irradiated to allow maximum cell kill. The computer system of portal visualization helps to exclude the possibility of human error.
A new high-precision method of remote radiotherapy (IMRT – Intensity Modulated Radiotherapy) is used for the treatment of patients on the linear accelerator in the Spizhenko Clinic. This unique method allows selecting exact dose, forming a powerful radiation beam and directing it to the tumor location. IMRT also allows protecting healthy organs and tissues located near the tumor.
The combination of IMRT radiotherapy with beam intensity modulation (Elekta Sinergy linear accelerator) and radiosurgical treatment with CyberKnife creates a unique opportunity for a significant improvement in the results of treatment of patients with cancer. The linear accelerator affects the tumors and metastases with large fields, and, at the end, the CyberKnife kills the residual cancer cells.