Case study on radio activity
P1: Describe radioactivity, including atomic structure
P3: Describe the production and detection of radiopharmaceuticals
P4: Explain the role of pharmaceuticals within the operating principles of the gamma camera
M1: Explain the random nature of decay and how it relates to half life
M2: Compare the desirable biological properties and radiological properties of radionuclides used for imaging
D2: Evaluate the choice of radiopharmaceuticals for a range of clinical imaging requirements
Task 1: Radioactivity – P1, M1
1) Describe in simple terms what happens when radioactive decay takes place.
To complete this activity successfully you should include diagrams and use the following terms: parent, daughter, unstable, stable, random, and include equations that illustrate examples of nuclides that decay by alpha, beta and gamma radiation) (P1)
2) The graph shows the average corrected count rate recorded per day over a 40 day period.
(i) Explain what is meant by the terms corrected count rate and half-life.
(ii) What is the value of the half life of the material?
(iii) What is the value of the decay constant?
(iv) Radioactivity is described as a Random Process. Explain what is meant by this term and how the graph demonstrates that radioactive decay is a random process. (M1)
Task 2: Nuclear Medicine – P3, P4, M2, D2
1. Describe how technetium 99m is produced in a Technetium Generator (You should include diagrams to aid your explanation) (P3)
2. Explain how the gamma radiation it emits is detected by the gamma camera, paying particular attention to the role of the Collimator, Scintillating Crystal, Photo cathode and Photomultiplier tubes. You should include a labelled diagram of the Gamma Camera to aid your explanation. (P4)
3. Different radiopharmaceuticals are used for different clinical investigations. Produce a small report on two Radionuclides that can be used for imaging a 2 different parts of the body Your report must include the following information:
– A brief description of the medical conditions being investigated
– Details of the Radionuclides used and the properties they have which make them suitable for your chosen investigations
– A series of annotated images showing the condition as seen under the Gamma Camera. Your annotations should describe the anatomy shown and explain key features of the image that aid diagnosis of the medical condition being investigated.
– An explanation of the advantages and disadvantages of using radionuclide imaging techniques for your chosen investigations from both a patients’ perspective, and from the perspective of the Clinical Care team
Part 2: Xrays and Ultrasound
Grading Criteria (For Part 2)
P2: Describe the production of x-rays and ultrasound
D1: Analyse the effect of the operation and design of the tube/head on a typical x-ray spectrum
Task 1 (P2)
Write a short report on Ultrasound imaging
Your report should include the following:
1. What is ultrasound?
2. What frequencies of ultrasound are used for medical imaging techniques?
3. How is ultrasound produced and how does the transducer work
4. Explain the principles of the pulse echo technique and how it can be used to produce an A scan, a B scan, real time imaging and M mode
5. What is the Doppler Effect and how is it used to measure blood flow velocity?
1) Explain how X rays are produced by a rotating anode X ray tube. You should include diagrams in your explanation (P2)
2) With reference to interactions between accelerated electrons incident on a target atom, explain the underlying physical principles behind the production of the 2 different parts of the X ray spectrum. The 2 parts of the spectrum are:
a) The Continuous Spectrum
b) The Line Spectrum
3) State the 3 factors which can affect the appearance of the spectrum from an X ray tube.
For each factor explain how the spectrum is affected and include a graph/s which illustrate you explanation. Your graphs need to show the appearance of the spectrum before and after each factor was changed.
Part 3: Radiotherapy and Radiation Safety
Grading Criteria (For Part 3)
P6: Explain the principles and effects of radiation therapy and the equipment used
M4: Explain how excessive exposure to radiation can cause harm
D4: Evaluate a range of therapy techniques, types of radiation available, and equipment used
1. Briefly describe the differences between the following therapy methods :Chemotherapy, Radioactive Implants, Superficial Therapy and Megavoltage Therapy (P6)
2. Explain the basic principle behind how LlNAC machine (Linear accelerator) generates X rays for Megavoltage Therapy and how its design & operation differs to a diagnostic Xray machine.
In addition explain 3 reasons why Cobalt 60 machines producing gamma rays are being phased out in the treatment of cancers, and replaced with LINAC machines.
3. With the aid of suitable diagrams, explain how each of the following limits the damage to healthy tissue
a. multiple beams
b. rotational beams
d. compensators (P6)
4. a. Explain the effects of ionising radiation on cells and tissue in malignant tumours and the importance of treatment planning to reduce damage to healthy tissue
b. In addition, for a particular department outline the measures that are taken to limit over exposure to ionising radiation for the patient and all staff
5. Different treatment methods as discussed in task 1 can be used for treating different forms of Cancer. Produce a report on two treatment methods that can be used for treating a 2 different forms of Cancer Your report must include the following information:
– A brief description of the Cancers being treated and the preferred treatment method
– An explanation of the advantages of using the preferred treatment method for your chosen Cancer.
– A discussion as to whether each of the remain treatment methods in task 1 could be used for treating your chosen Cancer
Part 4: MRI
Grading criteria (For Part 4)
P5: Outline the process of magnetic resonance imaging, and the instrumentation and equipment used
M3: Explain the factors influencing the intensity of the MRI signal
D3: Compare and evaluate the appearance of bone and soft tissue in and MRI scan and a conventional X ray
1. With reference to the relevant magnetic fields and proton behaviour, Create a block diagram of the MRI process. (P5)
2. Describe and explain using images/diagrams:
a) How the strong uniform magnetic field in an MRI scanner is produced and maintained
b) The purpose of the Gradient Coils
c) The purpose of the Radio Frequency coils
3. State 3 the factors that influence the intensity of the MRI signal. For each factor, explain the effect that it has on the MRI signal strength and hence intensity on an image.
4. Obtain 2 high-quality images of a conventional X ray and an MRI image for the same either the abdomen, head, spine or a joint.
Compare and evaluate the appearance of bone and soft tissue for both imaging techniques. You should make reference to the contrast between tissue types and resolution for the 2 images selected