MPHY3890/M890: Medical Imaging with Ionising Radiation


Course information

Unit value
Year of study
Course organiser
Second examiner
3 or 4
Term 2
Prof Alessandro Olivo
Dr John Dickinson
Dr Kris Thielemans


The course, taught during Term 1, forms part of the Physics with Medical Physics undergraduate degrees (B.Sc., B.Sc.(Intercal) and M.Sci.). It is an optional course for the BSc and compulsory for the B.Sc.(Intercal) and M.Sci. It provides essential knowledge regarding the production and assessment of clinical images using either x-rays or gamma rays.

Year 3 and Level 7 (previously called M-level) variants

This course can be taken in Year 3 as MPHY3890 or in Year 4 as an Level 7 (previously called M-level) variant called MPHYM890. The two variants differ in the amount of coursework, and the pass mark for the Level 7 variant is 50%.

Aims and Objectives

The course will demonstrate to the student the theoretical background, mode of operation and practical application of systems designed to image either anatomy or physiological function using ionising radiation. It will also introduce the student to the methods by which images can be processed and assessed.


  • To impart knowledge on the sources of radiation that can be used in clinical imaging and to develop the understanding of the interactions that are likely to take place in the patient and detector.
  • To impart knowledge and understanding on the detectors commonly used in X-ray and gamma ray imaging.
  • To impart knowledge on the more recently developed sensors that may in the future find applications.
  • To impart knowledge on systems that are used in gamma ray imaging.
  • To develop understanding in how image contrast can be improved in X-ray imaging.
  • To develop skills in simple calculations that deal with contrast in X-ray imaging.
  • To develop understanding of the parameters used to describe images.

Teaching and Exams

Teaching will consist of:

  • Lectures, 28 hours.
  • Seminars/problem classes, 5 hours.
  • Required written work (essays), 15 hours.
  • Private reading, 30 hours.

The assessment will consist of:

  • 1 Unseen written examination (2.5 hours) worth 80% of the total course mark.
  • 2 essays completed during term-time worth 20% of the total coursework.


We assume that you have met the minimum entry requirements for our undergraduate degree programmes (i.e. A level Mathematics (grade A preferred), Physics and one other A level at ABB or above, or equivalent). We also expect students to have taken at least one additional maths module in year 1 or 2. If you feel you meet the prerequisites through a non-standard route, please contact the module organiser. All variants of the modules have the same prerequisites.

Specific knowledge assumed:

Mathematics: Familiarity with manipulation of equations, basic calculus, exponentials, differentiation and integration; an ability to sketch and interpret graphs.

Physics: Basics of: radioactivity, electromagnetic spectrum, ionising radiation, atomic physics. Interactions of radiation with matter are key and will be revised at the beginning of the module, however some prior knowledge would be helpful.

Engineering: Fourier transforms are used. Although the basic concepts will be revised, some prior knowledge would be helpful.

Biology: None.

Other: None, but be aware that this module is about the physics of x-ray imaging, nuclear imaging, radiation protection: all lecturers are physicists, and it should be considered first and foremost a physics module. There are elements of engineering as far as the design and construction of imaging systems is concerned; provided examples are in medicine.


Ionising radiation has always been an important aspect of the application of physics to medicine. Within the UK at least 40% of the physical scientists employed in the NHS are involved in the use of ionising radiation whereas in the European Union the figure is estimated to be nearer 75%. The general philosophy for the teaching of the ionising radiation courses is that the principles rather than the practice are taught. Thus the aim of this course is to provide the theoretical background with practical examples to the production and evaluation of medical images created using x- or gamma radiation. The course is structured to look firstly at aspects of source design, followed by selected detector systems and finally some aspects of image evaluation. Where possible mathematical models are developed to help the understanding. The material is presented as a knowledge based course where ideas are developed from basic material delivered in other physics core courses. For example, sources are developed from the basics of atomic models and solid state physics, x-ray imaging systems are based upon Fourier transform descriptions from the mathematics courses. There is a reliance upon the student using the recommended texts to supplement the lecture material although the tutorial sessions can also be used to provide deeper detail.

Brief Syllabus

  1. General concepts of imaging, Different types of imaging, relative importance, summary of course and its aims, objectives and methods of assessment.
  2. Sources Diagnostic x-ray beams, outline of thick target theory, target types, spectral components and tube design. Radionuclide production, cyclotrons, generators and reactor production. Decay schemes, alpha, beta and gamma decay.
  3. X- and gamma ray interactions Revision of interactions in the patient and detector system relevant to imaging systems.
  4. Detectors for X-ray imaging X-ray film, physical properties of, derivation of characteristic curve and dependence of performance on variables in manufacture. Film/screen combinations, physical properties of, speed, rare earth screens, dose reduction. Image intensifiers, construction and mode of operation, Electrostatic detectors, multiwire proportional chambers and CCDs.
  5. X-ray systems and techniques Improving contrast in x-ray diagnosis, contrast media, subtraction radiography, controlling scatter, digital subtraction, tomography, computed tomography, gantry design, methods of image reconstruction.
  6. Detectors for nuclear medicine Scintillation detectors, photomultiplier tubes and associated electronics, pulse height spectrum, SCA and MCA. Gamma camera, construction and corrections.
  7. Systems and techniques in nuclear medicine The nuclear medicine computer, static images, list and frame mode, dynamic images, gated images, SPECT, scatter and attenuation, PET. Applications.
  8. Counting statistics, A to D conversion. Resolution, PSF, LSF and ERF, MTF. Contrast, subject, film and radiographic contrast, contrast enhancement and restoration. Distortion, geometrical and spatial frequency distortion, non linearity. Noise, quantum noise, granularity, autocorrelation function and Wiener spectrum.

Core Texts

  • H. E. Johns and J. R. Cunningham, The Physics of Radiology, Charles C. Thomas
  • S. Webb (Editor), Physics of Medical Imaging, Adam Hilger, 1988.
  • H. H. Barrett and W. Swindell, Radiological Imaging Vols I & II, Academic Press, 1981.
  • J. A. Sorenson and M. E. Phelps, Physics in Nuclear Medicine, Grune & Stratton, 2nd edition 1987.
  • G. B. Saha, Physics and radiobiology of Nuclear Medicine, Academic Press, 1993.
  • N. F. Kember (Editor), Medical Radiation Detectors, IOP Publishing, 1994. 
  • G. Herman, Image Reconstruction from Projections, Academic Press, 1980.
  • G. F. Knoll, Radiation Detection and Measurement, John Wiley, 1979.
  • K. Kouris, N. Spyrou, and D. Jackson, Imaging with Ionising Radiations, Surrey University Press, 1987.
  • F. A. Smith, A Primer in Applied Radiation Physics, World Scientific, 2000.