Ultrasound in a Needle: Minimally-invasive High Resolution Imaging for Neurosurgery

The research challenge we will tackle is to realise real-time visualisation of tissue in the brain with a needle capable of minimally-invasive, real-time, high resolution ultrasound imaging. This will, for the first time, enable the neurosurgeon to obtain immediate information about lesions and the location of critical structures in the brain intraoperatively, and thus to provide treatment with less morbidity and better patient outcomes.

Our specific engineering challenge is to create a needle carrying an integrated, miniature ultrasound array for high-resolution (~100 um) neurological imaging and to demonstrate feasibility for future translation into clinical practice. Previous EPSRC-funded collaboration by the Universities of Birmingham and Dundee has shown that piezocomposite material with microscale features can be realised with net-shape micromoulding techniques. Single element transducers based on these materials have been evaluated already and exploratory studies with Heriot-Watt University have demonstrated the capability to bond dense interconnects onto the new materials at low temperature and pressure to connect kerfless imaging arrays to external imaging electronics.

The research we now propose will extend and integrate this technical work with neurosurgery to determine basic capabilities using brain tissue in soft-embalmed cadavers and to explore potential surgical benefits and applications. As well as the three university partners, the work will benefit from support from four companies, covering all aspects of the technology as well as its translation into clinical practice.

This project on ultrasound in a needle has its foundation in the unmet need for a truly intraoperative means of imaging for neurosurgical operations, and the deleterious effects this has on outcomes for patients. Thus we will focus our activity in impact on the technical capabilities of ultrasound in a needle, its integration into procedures already used by neurosurgeons, and the need for commercial delivery of devices and systems so that neurosurgeons can access the technology.

Our pathways to economic impact will rely heavily on our four company partners, Applied Functional Materials Ltd (ultrasound devices), Merlin Circuit Technology Ltd (interconnects and packaging), Diagnostic Sonar Ltd. (ultrasound systems) and Scottish Health Innovations Ltd (SHIL, commercialisation of clinical technology). The first three represent key stakeholders in the technical delivery of USIN while SHIL bring understanding of the process of translation, from the research bench to the operating room. We will meet representatives of all these companies regularly and will utilise their input in the impact plan that we will update and act upon continuously.
In recognition that the present proposal is structured as a feasibility study and that the pathway from research to commercial supply and use in healthcare is a long one, a key component in our impact plan is to obtain further funding; this will be done in partnership with our existing company partners, and with others, for example in the regulatory and testing sectors, as these are required. Through the project leadership in IMSaT, we already have routes to ISO-accredited working practices and contacts with companies such as Onorach (on the design of clinical studies) and Precision Acoustics (on safety testing of ultrasound devices).

Our pathways to societal impact ultimately rely on the need for a commercial supply of devices. Societal impact will then follow from the improved patient outcomes that are generated. Approximately 20% of hospital admissions in the UK are for neurological conditions, ranging from minor conditions to those with very significant mortality, such as stroke. All those requiring surgical intervention will be considered as having the potential to benefit from USIN. The new weapon our research will create in the neurosurgeons armamentarium will have a particularly large impact on haemorrhage, making it easier to avoid in the first place during intracranial intervention, and quicker to deal with if it has already occurred. It will also allow more accurate diagnosis and evaluation of conditions such as brain cancer and better placement of devices such as cannullae for aspiration and electrodes for deep brain stimulation.
As well as their immediate effects, neurological disorders have significant potential for short and long term morbidity following from the original condition and its treatment. USIN may thus beneficially affect a whole chain of people in society, from the neurosurgeons and theatre teams who operate on the patients, to the people who care for them either intensively or in dealing with long term problems, through to the patients themselves and their families, friends and colleagues.