ELogs/JamesGolbourn

Electronic Log for James Golbourn

To Do

Short Term

• Write research essay.
• Update presentation with corrections made.
• Better understand beam uniformity (is it a function of depth?) - The SOBP longitudinal uniformity is defined as the maximum difference in the dose within the dose reference volume expressed as the percentage of the average dose within the reference volume. Normally part of weekly QA.
• Look at daily and monthly QA parameters.
• AAPM Task group no.224 set to publish daily machine QA procedures - but not published yet.
• Put links in wiki

Long Term

• Get in contact with Laurent contact at Med Austrom about QA procedures.
• Prepare practice presentation for project (8/2/19)
• Write up report on meeting with UCLH.
• Look at what functioning centres are using as QA.
• Look at advantages and disadvantages of QA systems.

Tasks Completed

• Presentation to PBT group.
• Project progress report.
• Project outline.
• First plan for research essay.
• Prepare practise presentation to Agapi.
• Email Alison for details of Haakan Nystrom.
• Met with Alison and Andrew form UCLH

Key Dates

Task	Deadline
Project Outline	03/12/2018
Project Progress Report	31/01/2019
Short Presentation	08/02/2019
Research Essay	31/03/2019
Thesis Deadline	22/08/2019
Final Presentation	02/09/2019

Research Essay First Plan

• Introduction:

1. What is PBT and the theory?
   1. Different methods of beam production
   2. Pencil beam scanning and uniform scattering.
2. What is Quality Assurance?
   1. Why is it needed?
   2. Relation to X-Ray QA and lack of consistency between facilities.
3. Beam parameters - what needs to be measured

• Sections on different beam properties and characteristics:
  • For each of these sections there should be a description of:
    • What is it?
    • Relation to patient dosimetry and why is it important?
    • Methods of measurement.

1. Beam energy and range
2. Beam output
3. Spot size and symmetry
4. Spot position and beam uniformity

• Commercial devices available for QA

1. IBA Lynx
2. IBA Matrixx
3. IBA Zebra
4. Sun Nuclear QA 3

• Various methods using these devices for QA

• Conclusion

Progress Report Outline

• Introduction to Proton beam therapy.
• What is Quality Assurance?
• Important beam characteristics.
• Commercially available devices such as the Matrixx, Lynx and Sun Nuclear QA3.
• Other methods for measuring beam properties.

Comments made about presentation

• Understand what range modulators do.
• Look into whether Zebra was initially designed for X-Rays.
• Zebra not often used for daily QA due to the very long initial set up time.
• Investigate film dosimetry e.g Gafchromic film.
• Research Lynx scintillator.
• Range calorimeter - need a moving absorber, e.g water tank, to measure energy and range.
• Know difference between scintillator screens and fibres - fibres use fibre optics and are not used due to needing something to read output from each fibre which is expensive.
• UCLH will have 4 treatment rooms.
• Put slide number on presentation.
• Expand on each daily QA:
  • Table of devices
  • Tolerances
  • How long it takes
• Collect standards and tolerances on energy, spot size and output.

Useful Links for Research Essay

Devices and Detectors

• Sun Nuclear QA 3 Device:
  • A novel daily QA system for proton therapy
    • https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5714372/
  • Daily QA in proton therapy using a single commercially available detector
    • https://aapm.onlinelibrary.wiley.com/doi/pdf/10.1120/jacmp.v15i6.5005
  • Sun Nuclear QA 3 Fact Sheet
    • https://www.sunnuclear.com/documents/datasheets/dailyqa3-rfdaily.pdf
  • Technical Note: An efficient daily QA procedure for proton pencil beam scanning
    • https://aapm.onlinelibrary.wiley.com/doi/10.1002/mp.12787

• IBA Zebra:
  • Quality assurance of proton beams using a multilayer ionization chamber system
    • https://aapm.onlinelibrary.wiley.com/doi/epdf/10.1118/1.4817481

• IBA Matrixx
  • Use of a two-dimensional ionization chamber array for proton therapy beam quality assurance, B Arjomandy Et al, Med Phys. 2008 Sep;35(9):3889-94
    • Method describing how the Matrixx can be used for measuring beam flatness and symmetry.
  • Quality assurance of carbon ion and proton beams: A feasibility study for using the 2D MatriXX detector, M Donetti Et al, Phys Med. 2016 Jun;32(6):831-7. doi: 10.1016/j.ejmp.2016.05.058. Epub 2016 May 28 .
    • Matrixx can be used to replace film dosimetry.

• IBA Lynx
  • Characterization of a commercial scintillation detector for 2-D dosimetry in scanned proton and carbon ion beams, S Russo et al, Physica Medica Volume 34, February 2017.
    • Investigates using the Lynx to measure spot size and position. Lynx can be used due to high spatial resolution.

• IBA Lynx and Sphinx
  • Range resolution and reproducibility of a dedicated phantom for proton PBS daily quality assurance, Zeitschrift für Medizinische Physik, Vol 28, Issue 4, December 2018.
    • Investigates combining the Sphinx and Lynx together for daily QA. The combination can be used to measure relative range using the Sphinx blocks as well as spot size and position with Lynx.

• Dosimetry for Ion Beam Therapy:
  • Looks at different detectors and what they can be used to measure.
  • https://iopscience.iop.org/article/10.1088/0031-9155/55/21/R01/meta#pmb318329s2