Radiation Treatment

Types of Radiation Therapy Types of Radiation Therapy

The type of radiation therapy that is given to each patient is dependent on the type of cancer, its location and the purpose of the radiation treatment. Your radiation oncologist will recommend what s/he feels would be best. The following types of radiation therapy are available in the Oklahoma City area through Optim Oncology:

Intensity Modulated Radiation Therapy

IMRT or Intensity Modulated Radiation Therapy is a type of external beam radiation therapy that targets the tumor and reduces exposure to normal tissue. IMRT uses hundreds of tiny radiation beam-shaping devices, called collimators, to deliver a dose of radiation to a specific target with a margin of a millimeter. Many times during a radiation treatment the therapists will take an image of the area to be treated, the treatment area will be aligned for the most accurate treatment, and the radiation dose will be administered.

With IMRT, the radiation oncologist is able to increase the radiation dose to the areas that need it and reduce radiation exposure to specific sensitive areas of surrounding normal tissue. 


Tomotherapy is a type of image-guided IMRT. A tomotherapy machine is a hybrid between a CT imaging scanner and an external-beam radiation therapy machine. It customizes delivery for each patient, targeting the cancer with highly-precise radiation delivered from all angles. This state-of-the-art radiation therapy procedure minimizes exposure to healthy tissue by delivering radiation beams 360 degrees around the cancer patient.

Image Guided Radiation Therapy

IGRT or Image Guided Radiation Therapy is the use of CT or Computed Tomography Scan, X-ray or other imaging to localize the tumor or target area during and/or prior to treatment. These imaging scans are used to identify changes in a tumor’s size and location due to treatment and help to reposition the patient and planned dose of radiation therapy based on how the cancer has changed. Your oncologist will continuously monitor the tumor size and location during the course of treatment.

Repeated imaging can increase the radiation treatment accuracy and decrease the total radiation dose to normal tissue. IGRT is used in conjunction with IMRT for the most optimal treatment results.

"No one chooses cancer. But you can choose where you receive treatment. I feel it's our job to guide our patients through this journey with the best in combined modality care. I know we're doing something right when someone we've helped brings a family member back to us for treatment. We're in this together."

- Dr. Christopher Bozarth                                               
Medical Director and Radiation Oncologist

Stereotactic Radiosurgery

SRS or Stereotactic Radiosurgery uses extremely accurate image guided targeting and patient positioning that is necessary to accurately treats small brain cancer and non-cancerous brain tumors. SRS allows for high doses of radiation to be given will minimizing damage to normal tissue.

SRS can be used to treat only small tumors with well-defined edges. It is most commonly used in the treatment of brain or spinal tumors and when another type of cancer has spread to the brain (metastasized). Despite the name, it is not actual surgery.

Stereotactic Body Radiation Therapy

Similar to SRS, SBRT, or Stereotactic Body Radiation Therapy administers very high doses of radiation, using multiple beams aimed at different angles to precisely target the tumor.

SBRT delivers radiation therapy in fewer sessions, using smaller radiation fields and higher doses than other types of external beam radiation. By definition, SBRT treats tumors that lie outside the brain and spinal cord. Because these tumors are more likely to move with the normal motion of the body, and therefore cannot be targeted as accurately as tumors within the brain or spine, SBRT is usually given in more than one dose, and can only be used to treat small, isolated tumors, including cancers in the lung and liver.

Calypso Treatment System

For patients with prostate cancer, the Calypso System localizes and tracks the position of the prostate throughout treatment. This provides the radiation oncologist and the radiation therapists the ability to view the movement of the prostate and make adjustments during a treatment session. The result is delivery of radiation therapy to the area within the body that actually needs it.

The system works by implanting Calypso beacons into the prostate. When activated, the beacons send signals to cameras located above the treatment station that show where the prostate is and any movement that might occur during treatment. If there is movement detected the radiation therapist can stop and make adjustments during the treatment session.