Medical Dosimetrist

Medical Dosimetrists 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 an empathetic 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.

The Responsibilities of the Medical Dosimetrist

The 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 optimally 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.


Brachytherapy requires a unique involvement by the Dosimetrist in the preparation of surgical packs, applicators and radioactive sources to be used by the Radiation Oncologist. In many instances, the Dosimetrist may accompany the physician in surgery to assist with the handling and logging of sources. Following the implantation, the Dosimetrist is responsible for calculating the total dose or dose rate to the implanted volume. After the patient is settled in the hospital room, it is the responsibility of the Dosimetrist and/or Physicist to monitor the room to establish safe distances for visitors, post radiation warning signs on the door, place any needed portable shields, and talk with the care nurses and the patient's family or friends regarding safety during the patient's stay. The Medical Dosimetrist needs to have the ability to communicate easily with Physicians, Physicists, Therapists, collateral health care individuals, patients and their families.


The American Association of Medical Dosimetrists was incorporated in 1975 by a small group of professionals. The society was organized exclusively for charitable, educational and scientific purpose within the field of medical physics and dosimetry. The organization continues to expand, and is now comprised of approximately 1500 members. The AAMD surveys and updates its members on important aspects of the profession such as job skills, salary levels, academic profiles and work environment. The Association is actively involved in the exchange of information in the interest of enhancing the profession of Medical Dosimetry.

Professional Goals:

To promote the proper and concise measurement of radiation.
To maintain proper and professional ethics within the profession.
To achieve professional performance through proper training and education.
To prepare and distribute information pertaining to Medical Dosimetry.
To clarify and strengthen the position of the Medical Dosimetrist within the Medical Community.

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The above information is courtesy of the American Association of Medical Dosimetrists