In Radiotherapy, medical physicists play a key role in the provision of the radiotherapy service as a whole.

1. The Role of a Physicist in
Radiation oncology
Medical Physicist / Mohamed Ali Morsy
Radiotherapy Department, Dar Al-fouad Hospital
Ph_moh_ali@yahoo.com
(+20- 01123600302)
by

2. Introdction:
According to the AAPM REPORT No. 38,
THE ROLE OF A PHYSICIST IN RADIATION ONCOLOGY Published for
the American Association of Physics in Medicine by the American Institute
of Physics
In Radiotherapy, medical physicists play a key role in the provision of the
radiotherapy service as a whole.
The physicist performs an important role working along with the radiation
oncologist, the radiotherapy technologist and others, to assure the
accurate delivery of all aspects of a treatment prescription.
Responsibilities of Radiation Oncology Physics In radiation oncology,
physicists have the primary responsibility for the following, except where
the responsibility is noted as shared.

3. The Role of a Physicist in Radiation oncology
1- Radiation Protection role:
1-Development and administration of the radiation safety program,
including compliance with all regulating and certifying.
2- Administration of a personnel radiation monitoring program.
3- Participation on the institutional Radiation Safety Committee,
and other committees (e.g., General Safety) as needed.
4- Calculation of shielding required for new or renovated treatment
rooms, radioactive-source storage and handling facilities, and
brachytherapy patient rooms

4. The Role of a Physicist in Radiation oncology
2- The physical aspects of patients treatments role:
1-Consultations with radiation oncologists on the physical and
radiobiological aspects of patients’ treatments, and the development of
treatment plans.
2- Calculation of dose distributions and machine settings for patient
treatments.
3- Design and fabrication of treatment aids and treatment-beam modifiers.
4- Assurance of the accuracy of treatment unit parameters and settings
used for a patient’s treatment, including correct transfer of parameters
between the simulator, treatment plan and the treatment unit.
5- In-vivo measurement to verify the dose delivered to a patient.

5. The Role of a Physicist in Radiation oncology
6- Assisting the radiation oncologists in statistical analysis for evaluation of
treatment efficacy, and participation in clinical trials.
7- Development of techniques (hardware, software, or procedural) to
improve the delivery of radiation treatments.
8- Continuing education of the radiation oncology staff.
9- Because of the training received in analytical processes and scientific
principles, the physicist plays a principal role in development of systems
and policies, the review of consistency between plans and their execution,
and problem-solving.

6. The Role of a Physicist in Radiation oncology
3- Physics assistants:
who usually begin their training with either a bachelor’s degree in
science, or prior training in radiotherapy technology, may perform
many routine physics functions under the supervision of a
physicist, such as:
1- Treatment-unit quality-assurance measurements.
2- Radiation-level readings around brachytherapy patients
.
3- Personnel radiation monitors handling

7. The Role of a Physicist in Radiation oncology
3- Medical Dosimetrist:
Dosimetrists are personnel specially trained in performing specified
physics tasks include:
1- Assembling patient data required for dose calculations,
2- Calculating dose distributions,
3- Manufacturing compensators, immobilization molds and related
devices, and custom-made blocks.
4- Computing treatment times or control monitor units ·
5- Performing in-vivo dosimetry for patient treatments,
6- Performing periodic checks on treatment records.
Many of these functions apply to both external
beam and brachytherapy treatments.
Dosimetrists perform these tasks under the
supervision of a physicist,

8. The Role of a Physicist in Radiation oncology
3- Medical Dosimetrist:
Dosimetrists are personnel specially trained in performingspecified physics
tasks include:
1- Assembling patient data required for dose calculations,
2- Calculating dose distributions,
3- Manufacturing compensators, immobilization molds and related
devices, and custom-made blocks.
4- Computing treatment times or control monitor units ·
5- Performing in-vivo dosimetry for patient treatments,
6- Performing periodic checks on treatment records.
Many of these functions apply to both external beam and brachytherapy
treatments. Dosimetrists perform these tasks under the supervision of a
physicist,