Radiation Oncology Department: University of Arizona

What is a Medical Dosimetrist?

What Is A Medical Dosimetrist?
A Medical Dosimetrist are members of the Medical Physics section of the Radiation Oncology Team. They work under the supervision of the Medical Physicist, and are skilled in calculating and planning radiation doses.

This is a very responsible and technical profession within the medical community, and the Medical Dosimetrist must have an extensive background in formal education and experience. Educational backgrounds may vary; ideally, they are certified by the Medical Dosimetrist Certification Board. They may be college graduates with a physics and/or mathematics background who have been clinically trained by qualified personnel. Some may be Radiation Therapists with many years of clinical experience and training by Medical Physicists in dosimetry.

A close working relationship with physicians, physicists and therapists, and a compassionate desire to help their patients is necessary. The Dosimetrist must also have the desire for and express the willingness to stay current through continuing education in this rapidly changing field.

Medical Dosimetry is the measurement and calculation of dose for the treatment of cancer patients. This is accomplished by various means; the uses of meters, chemicals, detection devices and computers. Following these measurements the information is presented to the Radiation Oncologist for approval before the application of the actual treatment to the patient. Primarily, dosimetry is the metering and measurement of dose by whatever method is most suited to the current situation.

Responsibilities of a Medical Dosimetrist
A Medical Dosimetry career has developed because of the necessity of precision in the treatment of cancer. Professional Dosimetrists use their knowledge of physics, anatomy and radiobiology to develop an optimal arrangement of radiation portals and exposures to spare normal and radiosensitive tissues while applying a prescribed dose to the targeted disease volume.

Prior to the development of any treatment plan, the Dosimetrist must consult with the physician and many times accompany and assist him or her while the patient is being examined. This is often necessary to determine the targeted volume of the disease and its surrounding area, and to ascertain which normal tissues need to be avoided. The complexity of the disease and a patient's underlying health problems frequently require that several plans be computed. The Radiation Oncologist, along with the Medical Physicist will make the decision as to which plan will serve the patient's best interests. The Dosimetrist may then calculate the doses and explain the treatment plan to the Therapists who are responsible for administering the daily treatments.