MPHY3892/M892: Treatment using ionising radiation

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Course information

This course also has a Moodle page.

Unit value
Year of study
Term 1
Course organiser
Second examiner
Other lecturers
0.5
3 or 4
Term 1
Dr Adam Gibson
Prof Gary Royle
Dr Konstantin Lozhkin

Aims

To provide basic knowledge of how patients are treated using ionising radiation and a theoretical knowledge how the therapeutic effect is produced. The basic concepts of radiation protection are also described.

Year 3 and M-level variants

This course can be taken in Year 3 as MPHY3892 or in Year 4 as an M-level variant called MPHYM892. The M-level variant has an additional essay, and a higher pass mark of 50%.

Objectives

  • To impart knowledge and understanding of dosimetry for ionising radiation.
  • To impart knowledge on the radiobiological basis of ionising radiation treatment.
  • To impart knowledge on methods used for planning the treatment of patients with ionising radiation.
  • To impart knowledge and understanding of concepts in radiation protection.

Teaching and assessment

Teaching will consist of:

  • Lectures, ~22 hours.
  • A problem-based learning assignment, ~10 hours (timetabled). This also forms the coursework, so you are expected to contribute additional time.
  • Private reading, ~10 hours


For MPHY3892, the assessment will consist of:

  • 1 unseen written examination (2 hours) worth 60% of the total course mark.
  • A problem-based learning assignment, assessed by report and presentation and worth 40% of the total course mark.


For MPHYM892, candidates will complete an extra piece of coursework, so the assessment will be:

  • 1 unseen written examination (2 hours) worth 50% of the total course mark.
  • A problem-based learning assignment, assessed by report and presentation and worth 40% of the total course mark.
  • An essay, worth 10% of the total course mark.

Prerequisites

There are no strict prerequisites.

Description

The course provides the basic knowledge which a medical physicist working in a radiotherapy department would be expected to have.

This includes:

  • a knowledge of how quantities of radiation and radiation doses are measured
  • the theory of radiation detectors and dosemeters
  • a knowledge of how cells are affected by exposure to ionising radiation and the mechanisms involved
  • knowledge of how the treatment plan for a patient is developed and carried out
  • a knowledge of the risks involved in the use of ionising radiation and the concepts of risk and radiation protection.

Brief Syllabus

Dosimetry
Revision of basic concepts; Absorbed dose, Kerma, charged particle equilibrium. Calorimeters for total beam energy. Ionisation dosimetry, free-air chamber, air-wall chambers in theory and practice. Bragg-Gray theory, improvements and corrections. Electron chambers. TLD, film and semi-conductor dosimeters.

Radiobiological basis
Revision of important aspects of interactions of photons and charged particles. Biological effects of radiation, DNA damage, target theory and DNA repair. Cell survival curves and their interpretation. Physical factors (dose rate, LET), biological factors (oxygenation, cell sensitisers). Acute effects, doses and death times. Genetic effects, effects on reproductive system. Carcinogenesis. Environmental radiation sources, man-made radiation sources and levels. Cell killing, fractionation, repair, etc.

Dose distribution & radiotherapy treatments
Sealed and unsealed source therapy. External sources, depth doses, build-up, back-scatter. Isodose distributions. Conformal and image guided radiotherapy. Electron beam distributions. Practical systems to treat patients, radiotherapy planning.

Radiation protection
Stochastic and non-stochastic effects, risk estimates. Human experience of radiation effects. ICRP, ALARA. External source protection, shielding calculations. Internal sources and dosimetry.

The problem-based learning experience

For this course, some of the lectures and all the coursework is used for a problem-based learning exercise where you are put into groups and given a problem to solve. Here are some comments from students who completed this exercise:

"It's been an incredibly rewarding experience ... I think the group worked well as a team and was well organised ... the results (and the process) were incredibly satisfying and I'd be happy to work with this group again on another problem!"

"The group worked really well together, because of this we finished the report with plenty of time to spare and without any undue stress. The word limit of 2500 words meant that we each had lots more that we could have contributed. Through the whole project we made sure that we were working as a team. This meant that we each contributed equally to the final project, and that no one felt they had contributed disproportionally."

"Every member of the team worked hard and well so we ended up with a high quality final piece that I thoroughly enjoyed working on."

"I feel through the task that I as a medic got a greater appreciation of the physics behind the therapies and the physicists within the group gained a better knowledge of the anatomy and physiology of cancer than either of us would have through passive lectures."

"This assignment has definitely improved my teamwork skills and has furthered my understanding of grant applications and scientific investigations, no doubt useful skills for later in life."

Core Texts

  • E B Podgorsak (2005) “Radiation oncology physics” IAEAM.
  • Tubiana, J. Dutreix, A. Wambersie, Introduction to Radiobiology, Taylor & Francis, 1990. 
  • J. E. Coggle, Biological Effects of Radiation, Taylor & Francis, 1983.
  • F. H. Attix, Introduction to Radiological Physics and Radiation Dosimetry, J. Wiley & Sons.
  • Williams and Thwaites (2000) “Radiotherapy physics in practice” Oxford Medical
  • S. R. Greening, Fundamentals of Radiation Dosimetry, (Medical Physics Handbook 15), Adam Hilger.
  • Jane Dobbs, Ann Barrett and Daniel Ash (1999) Practical Radiotherapy Planning, Arnold.
  • T. J. Godden, Physical Aspects of Brachytherapy, Adam Hilger, 1987.