Improving patient safety with the MOSkin dosimeter

Fields of Research

  • 02 - Physical sciences
  • 11 - Medical and health sciences

Socio-Economic Objectives

  • 92 - Health
  • 93 - Education and training
 

Keywords

  • Radiotherapy
  • Brain cancer
  • Breast cancer
  • Prostate scancer
  • Gynaecological cancer
  • Radiation dosimetry
  • Brachytherapy
  • MOSFET
  • MOSkin

UN Sustainable Development Goals

  • 3 - Good health and well-being
  • 9 - Industry, innovation and infrastructure

Impact

Impact Summary

UOW physics research has generated a technology that reduces the risk to radiotherapy patients from increasing exposure to radiation medicine through real-time quality assurance of radiation doses. The Centre for Medical Radiation Physics (CMRP) pioneered silicon detector technology for radiation dosimetry, which was developed into the MOSkin device. The award-winning MOSkin device has been implemented clinically in three hospitals (Australia, Italy and Malaysia), improving the safety and clinical outcomes of more than 250 patients. MOSkin facilitated a change in clinical protocols, reducing treatment planning time, while maintaining its precision. CMRP research further improved capacity-building through the training of over 30 per cent of radiotherapists in NSW.

Related United Nations Sustainable Development Goals:

3. Good health and well-being
9. Industry, innovation and infrastructure

Read details of the impact in full

Details of the Impact

Research in the Centre for Medical Radiation Physics (CMRP), led by Professor Anatoly Rozenfeld, generated technological, health and societal impacts through the development of the MOSkin device. The research generated (i) technological benefits through the development and commercialisation of the MOSkin radiation dosimetry device, (ii) health industry benefits by preventing radiation overdose in clinical treatments and providing more accurate measurements of the dose, thus improving the overall radiation regimen, and (iii) societal benefits through the increased safety of patients exposed to radiation during radiology or radiotherapy for treatment of various cancers (prostate, gynaecological, breast, brain) that may incur pain, avoidable tissue damage and severe toxicity. Further benefits were realised through the training and educational activities associated with MOSkin research: 30% of radiotherapists in NSW were trained at CMRP.

CMRP research [1–4] showed that metal-oxide-semiconductor field-effect transistor (MOSFET) radiation dosimetry devices provide unprecedented, real-time accuracy if the gold and nickel electrodes (commonly used for device die packaging) are optimised together with a fine control of the device “drop-in” packaging. The research team prototyped, tested and commercialised this technology into MOSkin, along with a wireless reader and acquisition software for real-time data processing. The package is available for purchase by hospitals through research contracts.

This led to invited contributions by Prof Rozenfeld and his group in several clinical trials where MOSkin was used to monitor radiation doses absorbed by radiation-sensitive organs at risk in different cancer treatments in over 20 cancer centres, hospitals and research institutes. These included: PROMETHEUS (Phase 2) stereotactic prostate radiotherapy at Calvary Mater Hospital in Newcastle, NSW; gynaecological high dose rate brachytherapy rectal wall dosimetry at the Italian National Institute of Tumours in Milan (Italy); and interventional radiology at Malaya Medical Centre in Kuala Lumpur (Malaysia).

At Calvary Mater Hospital during the SPARK Clinical Trial (NCT02397317) in 2016, two high dose fractions were delivered to patients with rectal retractors in place and MOSkin was used in 18 patients to monitor, in real-time, the dose delivered to the rectal wall and urethra. It will be used to monitor the remaining 30 patients still to be enrolled. Without MOSkin monitoring, the patients risk having the rectal wall or the urethra irradiated and later developing serious toxicity-related issues during their post-treatment disease management.

At the Italian National Institute of Tumours, MOSkins were used to monitor the dose absorbed in high dose rate brachytherapy treatments of prostate and gynaecological cancers. MOSkin was the first device in the world to be introduced into the clinical protocol for in-vivo dose (IVD) monitoring of the rectal wall dose in prostate cancer radiation treatment. The use of MOSkin led to a significant, 10% increase in the Quality Index (QI) for this treatment in more than 120 prostate cancer patients treated up to 2016. After the successful experience in prostate cancer brachytherapy, the hospital has also adopted MOSkin for gynaecological cancers. Fifty patients have been treated for gynecological cancers and monitored by MOSkin. The MOSkin is uniquely flexible, enabling it to be integrated into the water sheet of a transrectal ultrasound probe where it is used to monitor the dose delivered to the rectum in real-time. No other technology allows this.

Clinical application of several MOSkins helped physicians at the Milan hospital demonstrate that the uncertainty of the delivered dose is significantly higher if the delay between imaging and treatment exceeds 1.5 hours. This directly led to a change in clinical protocols, aimed at reducing the treatment planning time without sacrificing the treatment planning accuracy. IVD using MOSkins further demonstrated how intra-fraction variations of the rectum position can be significant and lead to substantial variation in rectal wall dose. Reliable information about the dose delivered to the rectal wall provided by IVD were recorded and reported and are now used as supplementary data in radiation-related morbidity studies. The Milan hospital has now adopted MOSkin, without altering their normal treatment procedure, to detect any large discrepancies between the measured and calculated dose to the rectal wall.

The Malaya Medical Centre in Kuala Lumpur adopted MOSkin dosimeters in two different programs to:

(i) investigate the radiation dose absorbed by a patient’s eye lens during neurointerventional radiology procedures. In a letter provided by the Malaya Medical Centre, “…to date, in-vivo dosimetry of patient eye lens dose has been performed on 35 patients […]. This cohort included 19 diagnostic angiographies, 8 cerebral aneurysm treatments and 8 embolization of arterial venous malformations. Among these patients, 9 were found to receive higher eye lens dose than the threshold dose for formation of cataract (500 mGy).” MOSkin technology alerted the operators to the high dose received by the eye lens, even though conventional procedures indicated acceptable doses. The MOSkin was instrumental in preventing organ threshold radiation overdosing. The letter further states: “Real-time monitoring of the MOSkin system has direct impact on patients’ safety during clinical interventional procedures.”

(ii) measure the skin dose in tangential breast radiotherapy. MOSkin has been adopted for 30 patients to monitor the skin dose absorbed during tangential 3D conformal breast radiotherapy. This clinical application has proven that in some cases the skin doses have exceeded the threshold limit for development of severe skin toxicity and the radiation procedure had to be stopped before the patients experienced painful adverse reactions.

Beneficiaries

  • Cancer patients
  • Radiotherapists
  • Calvary Mater Hospital (Newcastle) – Australia
  • Cancer Care National Institute (Milan) – Italy
  • Malaya Medical Centre (Kuala Lumpur) – Malaysia

Countries

Impacted Countries
  • Australia
  • Italy
  • Malaysia

Approach to Impact

Summary of the approaches to impact

In our approach to impact we rely on physics being the underlying discipline to all modern technologies. Our strategy aims to generate economic and social impact by establishing applied research centres, underwriting the costs of protecting and sustaining intellectual property, providing assistance in seeking funding for R&D and commercialisation, embedding research students in partner organisations and providing significant capacity for the training of the future workforce. We enhance our impact with the education and training of the next generation of Australian medical physicists, scientists, innovators and entrepreneurs through our strong outreach and STEM programs.

Read the full approach to impact

Approach to Impact

Our strategy begins with recognition of the potential for physics-based research to provide practical benefits to society through technical innovation and translation into tangible deliverables. These benefits are realised by investing in world-class applied research centres, supporting and protecting intellectual property, assisting in securing external funding, embedding research students with end-user organisations, and leveraging research to build capabilities in medical radiation physicists and radiotherapists.

Our impact is facilitated through our applied research centres, the Centre for Medical Radiation Physics (CMRP) and Institute for Superconducting and Electronic Materials (ISEM).

CMRP is our hub for medical radiation physics research and partners with 29 hospitals and research institutes, including a dozen overseas institutes. The centre is dedicated to the development of semiconductor detectors and dosimeters for clinical applications in radiation protection, radiation oncology and nuclear medicine as well as applications to high energy physics.

ISEM is our condensed matter physics research institute specialising in energy-related materials, semiconductors and superconductors with strengths in THz spectroscopy. The institute generates impact through collaborations with major industry partners and health districts (for example in superconductor research for magnetic resonance imaging) and developing technologies (for example battery management system research to deliver battery-powered personnel vehicles to major Australian mining companies).

Our central Innovation and Commercial Research (ICR) unit supports our research and development activity by dedicating personnel and resources for the evaluation of potential domestic and international markets, evaluation of the risk and costings of penetration of a new instrumentation into new markets.

ICR supported CMRP in preparing 7 patent applications over the last 10 years including patent protection for the project MOSkin, which has been filed in Australia, US and China. The overall patent portfolio of CMRP comprises 17 patents, with support for MOSkin IP and related technologies amounting to approximately $278k in the period.

The MOSFET technology behind the project MOSkin is protected by a patent filed by Prof Rozenfeld in Australia in 2007, China in 2008 and the United States in 2014. The support from ICR has protected the “drop-in” technology in these very competitive markets.

ICR also provides expertise for industry-partner negotiations with hospitals and private enterprises, and the management and amendment of contracts as required. Our commercialization managers help to identify funding opportunities such as the Commercialisation Australia Skills and Knowledge grant (2013) for the MOSkin project. This highly competitive grant funded the development of an effective commercialisation go-to-market strategy to transfer the MOSkin technology to the global market.

From 2010–16, ICR dedicated 0.5 FTE to support CMRP industry engagement activities. This support included developing IP commercialisation strategies, conducting business development activities, providing support for grant applications (particularly commercialisation strategies), and maintaining a general overview of all contractual obligations in regards to IP to ensure it is managed in a coherent manner.

The Research and Innovation Division at UOW also manages the ethics approval for research projects, a process that is particularly important for Medical Physics.

Beyond the MOSkin project, our researchers benefitted from support in applying for 15 grants in collaboration with end-users. The project “Solid State Microdosimetry” exemplifies our strong links with industry. For this project, CMRP initiated an international collaboration with SINTEF (Norway), a semiconductor facility. SINTEF committed to produce the sensor, designed and developed by CMRP, for the European market for space (the European Space Agency is the main contractor) and hadron therapy facilities.

We also integrate our research students into our collaborations with partner organisations, deepening relationships and increasing the potential for impact. For example, CMRP PhD student Anna Romanyukha undertook a six-month clinical attachment at the Istituto Nazionale dei Tumori (Milan-Italy) to translate the MOSkin technology for the benefit of gynaecological cancer patients.

Her results, obtained in collaboration with Italian medical physicist Dr Chiara Tenconi, led to the research project ‘In-Vivo Wall Dosimetry in Gynaecological HDR Brachytherapy Using a Semi-Flexible Rectal Probe Provided with MOSkin Dosimeters’, which was recognised for its excellence with an award at the 2016 World Congress of Brachytherapy.

Importantly, one of the key pathways to impact is through the training of medical radiation physicists and radiotherapists, who must keep abreast of rapid developments in the field of radiotherapy. CMRP not only plays a major role in developing medical physics researchers but has also trained 30% of radiotherapists in NSW.

Our engagement of the wider public is conducted through social and public media, and direct contact with high schools, aimed at promoting STEM disciplines that are essential for the development of innovative commercial research in Australia. One of our key goals is to narrow the gender gap in STEM disciplines. With this focus on gender balance, the 2016 “UOW Women of Impact” booklet featured an article on Dr Susanna Guatelli as a model for women aiming for a career in physics.

Media coverage and University publications such as the “40 Years of Research Impact” and “UOW Partners for Research Impact” helped translate and promote our impact. The former featured an article on silicon detectors for radiotherapy (CMRP) and materials science and the latter featured an article on MOSkin.

Associated Research

CMRP pioneered an award-winning instrument for accurate and reliable real-time measurement of radiation absorbed by the skin. This started in 1993 with the first detector prototype of MOSkin, incorporating the patented “drop-in” packaging technology.

a) MOSkin underlying technology: The principle for using MOSFETs as radiation monitors is well known [1–3]. The characteristic response of MOSFETs to radiation depends on many manufacturing parameters and it is challenging to produce a device that provides the reproducibility required for clinical radiation dosimetry applications. CMRP developed a proprietary fabrication process to manufacture MOSFETs with a very high reproducibility and radiation sensitivity. The sensitive layer is a few hundreds of nanometres thick, giving rise to sub-micrometre spatial resolution.

b) Drop-in technology: CMRP refined and patented [6] the drop-in technology; this packaging technique allows to manufacture a controllable and reproducible “water equivalent depth” of 0.07 mm, equivalent to the internationally defined epithelial layer of the skin [7], for any type of solid state detector. Competing radiation dosimetry devices are unable to measure the doses absorbed by human skin because of the device design and packaging that is too thick, not finely controllable and mechanically unreliable for this purpose. Others perturb the incident radiation field, rendering them unsuitable for real-time applications. The drop-in technology solved this issue.

References

1. Kwan, I.S., Rosenfeld, A.B., Qi, Z.Y., (...), Chin, Y., Perevertaylo, V.L. “Skin dosimetry with new MOSFET detectors” 2008 Radiation Measurements 43(2–6), pp. 929–932
2. Hardcastle, N., Cutajar, D.L., Metcalfe, P.E., (...), Tomé, W.A., Rosenfeld, A.B. “In vivo real-time rectal wall dosimetry for prostate radiotherapy” 2010 Physics in Medicine and Biology 55(13), pp. 3859–387
3. Kertzscher, G., Rosenfeld, A., Beddar, S., Tanderup, K., Cygler, J.E. “In vivo dosimetry: Trends and prospects for brachytherapy” 2014 British Journal of Radiology 87(1041), 20140206
4. Jong, W.L., Wong, J.H.D., Ung, N.M., (...), Cutajar, D.L., Rosenfeld, A.B. “Characterization of MOSkin detector for in vivo skin dose measurement during megavoltage radiotherapy” 2014 Journal of Applied Clinical Medical Physics 15(5), pp. 120–132
5. International Clinical Trial Registry: ClinicalTrials.gov Identifier: NCT02397317. https://clinicaltrials.gov/ct2/show/NCT02397317?term=sidhom&cntry=AU&rank=1
6. A.B.Rozenfeld “Radiation Sensor and Dosimeter” (MOSkin), 4 June 2007 and application number is 2007903003, Australian Patent. PCT/AU2008/000788 , filed 2 June, 2008 (WO 2008/148150 A1), China Patent ZL 200880023328.8, 5th December, 2012, US Patent N 8,742,357 B2 Date of Patent June 3, 2014
7. ICRP Task Group, “The biological basis for dose limitation in the skin. A report of a Task Group of Committee 1 of the International Commission on Radiological Protection”1992 Annals of the ICRP 22(2) pp. 1–104.