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Surveying trends in radiation oncology medical physics in the Asia Pacific Region

Kron T, Healy B, Ng KH

Phys Med, 2016 Jul;32(7):883-8.
PMID: 27320695 DOI: 10.1016/j.ejmp.2016.06.001

OBJECTIVE: Our study aims to assess and track work load, working conditions and professional recognition of radiation oncology medical physicists (ROMPs) in the Asia Pacific Region over time.
METHODS: A structured questionnaire was mailed in 2008, 2011 and 2014 to senior medical physicists representing 23 countries. The questionnaire covers 7 themes: education and training including certification; staffing; typical tasks; professional organisations; resources; research and teaching; job satisfaction.
RESULTS: Across all surveys the response rate was >85% with the replies representing practice affecting more than half of the world's population. The expectation of ROMP qualifications (MSc and between 1 and 3years of clinical experience) has not changed much over the years. However, compared to 2008, the number of medical physicists in many countries has doubled. Formal professional certification is only available in a small number of countries. The number of experienced ROMPs is small in particular in low and middle income countries. The increase in staff numbers from 2008 to 2014 is matched by a similar increase in the number of treatment units which is accompanied by an increase in treatment complexity. Many ROMPs are required to work overtime and not many find time for research. Resource availability has only improved marginally and ROMPs still feel generally overworked, but professional recognition, while varying widely, appears to be improving slowly.
CONCLUSION: While number of physicists and complexity of treatment techniques and technologies have increased significantly, ROMP practice remains essentially unchanged over the last 6years in the Asia Pacific Region.
An international survey of imaging practices in radiotherapy

Martin CJ, Kron T, Vassileva J, Wood TJ, Joyce C, Ung NM, et al.

Phys Med, 2021 Oct;90:53-65.
PMID: 34562809 DOI: 10.1016/j.ejmp.2021.09.004

Improvements in delivery of radiation dose to target tissues in radiotherapy have increased the need for better image quality and led to a higher frequency of imaging patients. Imaging for treatment planning extends to function and motion assessment and devices are incorporated into medical linear accelerators (linacs) so that regions of tissue can be imaged at time of treatment delivery to ensure dose distributions are delivered as accurately as possible. A survey of imaging in 97 radiotherapy centres in nine countries on six continents has been undertaken with an on-line questionnaire administered through the International Commission on Radiological Protection mentorship programme to provide a snapshot of imaging practices. Responses show that all centres use CT for planning treatments and many utilise additional information from magnetic resonance imaging and positron emission tomography scans. Most centres have kV cone beam CT attached to at least some linacs and use this for the majority of treatment fractions. The imaging options available declined with the human development index (HDI) of the country, and the frequency of imaging during treatment depended more on country than treatment site with countries having lower HDIs imaging less frequently. The country with the lowest HDI had few kV imaging facilities and relied on MV planar imaging intermittently during treatment. Imaging protocols supplied by vendors are used in most centres and under half adapt exposure conditions to individual patients. Recording of patient doses, a knowledge of which is important in optimisation of imaging protocols, was limited primarily to European countries.
Medical physics aspects of cancer care in the Asia Pacific region: 2014 survey results

Kron T, Azhari HA, Voon EO, Cheung KY, Ravindran P, Soejoko D, et al.

Australas Phys Eng Sci Med, 2015 Sep;38(3):493-501.
PMID: 26346030 DOI: 10.1007/s13246-015-0373-2

It was the aim of this work to assess and track the workload, working conditions and professional recognition of radiation oncology medical physicists (ROMPs) in the Asia Pacific region over time. In this third survey since 2008, a structured questionnaire was mailed in 2014 to 22 senior medical physicists representing 23 countries. As in previous surveys the questionnaire covered seven themes: 1 education, training and professional certification, 2 staffing, 3 typical tasks, 4 professional organisations, 5 resources, 6 research and teaching, and 7 job satisfaction. The response rate of 100% is a result of performing a survey through a network, which allows easy follow-up. The replies cover 4841 ROMPs in 23 countries. Compared to 2008, the number of medical physicists in many countries has doubled. However, the number of experienced ROMPs compared to the overall workforce is still small, especially in low and middle income countries. The increase in staff is matched by a similar increase in the number of treatment units over the years. Furthermore, the number of countries using complex techniques (IMRT, IGRT) or installing high end equipment (tomotherapy, robotic linear accelerators) is increasing. Overall, ROMPs still feel generally overworked and the professional recognition, while varying widely, appears to be improving only slightly. Radiation oncology medical physics practice has not changed significantly over the last 6 years in the Asia Pacific Region even if the number of physicists and the number and complexity of treatment techniques and technologies have increased dramatically.
Erratum to: Brief histories of medical physics in Asia-Oceania

Round WH, Jafari S, Kron T, Azhari HA, Chhom S, Hu Y, et al.

Australas Phys Eng Sci Med, 2015 Sep;38(3):525.
PMID: 26349560 DOI: 10.1007/s13246-015-0370-5
Brief histories of medical physics in Asia-Oceania

Round WH, Jafari S, Kron T, Azhari HA, Chhom S, Hu Y, et al.

Australas Phys Eng Sci Med, 2015 Sep;38(3):381-98.
PMID: 25894289 DOI: 10.1007/s13246-015-0342-9

The history of medical physics in Asia-Oceania goes back to the late nineteenth century when X-ray imaging was introduced, although medical physicists were not appointed until much later. Medical physics developed very quickly in some countries, but in others the socio-economic situation as such prevented it being established for many years. In others, the political situation and war has impeded its development. In many countries their medical physics history has not been well recorded and there is a danger that it will be lost to future generations. In this paper, brief histories of the development of medical physics in most countries in Asia-Oceania are presented by a large number of authors to serve as a record. The histories are necessarily brief; otherwise the paper would quickly turn into a book of hundreds of pages. The emphasis in each history as recorded here varies as the focus and culture of the countries as well as the length of their histories varies considerably.
Cone beam CT (CBCT) in radiotherapy: Assessment of doses using a pragmatic setup in an international setting

Djukelic M, Martin CJ, Abuhaimed A, Kron T, Gros S, Wood T, et al.

Phys Med, 2025 Feb 21;131:104937.
PMID: 39985958 DOI: 10.1016/j.ejmp.2025.104937

INTRODUCTION: The imaging modality kV CBCT on linear accelerators (linacs) is utilised to verify positioning and anatomy in cancer patients undergoing radiotherapy treatment. There is a need for optimisation of radiological protection in kV CBCT imaging protocols to avoid unnecessarily high exposures to normal tissues surrounding the target.
METHODS: A network of ICRP mentees from 23 countries were surveyed for available dosimetry equipment. Standardised measurements on CBCT linac imaging systems were conducted using a cone beam dose index (CBDI) devised as a straightforward measurement for wide beam doses. Measurements were made with (a) 100 mm ionisation chambers or (b) 0.6 cc Farmer ionisation chambers and cylindrical CT PMMA phantoms, and (c) an alternative setup of Farmer chambers and cubical phantoms comprised of slabs of water equivalent material readily available in radiotherapy centres. The measurements were compared with Monte Carlo (MC) simulations.
RESULTS: The survey showed limited availability for the reference setup using 100 mm chambers and CT phantoms. Correction factors were derived to convert normalised CBDI from alternative setups to the reference setup and are on average within 2% of MC simulations.
CONCLUSION: The slab phantom in combination with a Farmer chamber provides an alternative to quantify CBCT radiation dose indices from linac-based image-guided radiotherapy using materials accessible in most centres worldwide. A method is presented to use correction factors for Varian Truebeam linacs if traditional 100 mm chambers and cylindrical CT phantoms are not available. This will enable most radiotherapy centres across the world to engage in meaningful imaging dose measurement and optimisation.