High spatial and temporal resolution imaging of gut structure and microcirculation in response to nutrition intake and to therapeutics

Aim of the PhD Project:
Develop advanced ultrasound technology for high spatial and temporal resolution in vivo imaging of gut structure and function
Develop optimised signal and image processing and machine learning technology in the presence of fat layers and tissue motion
Study the impact of nutrient intake, inflammation and therapeutic agents on gut structure and microcirculation during mucosal healing in vivo
Project Description:
Recent advances in our understanding of the gut demonstrated that it is not only crucial for nutrient absorption but is also an integral part of the body's immune system. A healthy gut benefits nearly every aspect of human health, protecting us from nutrient deficiencies, inflammation, obesity, diabetes, immune diseases, infections, heart disease and cancer. There is now also overwhelming evidence that a healthy gut protects against many mental health disorders including depression, anxiety and autism.
The ability to quantitatively assess gut health, identify pathological conditions (e.g. inflammation), and monitor the gut's ability to repair (mucosal healing) and respond to food intake and therapeutic agents, is key to further our understanding of this complex system, to the development of new drugs, and to the clinical management of patients with gut disorders and drug development. Recent clinical observational data and real-world evidence support the use of mucosal healing as a clinical endpoint in treatment of Inflammatory Bowel Disease (IBD). However the gut mucosa takes a long time to heal and therefore objective evidence of inflammation of the bowel and longitudinal changes to mucosal healing are necessary when making clinical decisions. However, currently our ability to measure gut health in vivo is very limited, and often involves either indirect or invasive procedures.
Microvascular blood flow in the gut reflects changes in tissue activity. There is compelling evidence that specific regions of the gut precisely regulate their own blood flow to meet the local demands of absorptive, metabolic and repair processes. There is evidence that particular nutrients and metabolites, as well as some therapeutic agents, stimulate greater changes in blood flow which are correlated with reduced inflammation and improved mucosal healing. However, to date these changes in blood flow have mainly been studied invasively or in ex-vivo tissues.
Several recent advances in biomedical ultrasound, including 1) ultrafast data acquisition with up to tens of thousands of imaging frames per second, 2) microbubble contrast agents allowing high contrast imaging of blood flow, and 3) super-resolution ultrasound achieving sub-diffraction limited resolution, have made it possible to non-invasively image in deep tissue the microvascular morphology and flow dynamics with a resolution of tens of microns. We have been among the first to demonstrate ultrasound super-resolution in vitro and in vivo.

These advances in ultrasound present exciting opportunities for non-invasive in vivo measurement of gut structure and function, offering spatial and temporal resolution unmatched by other imaging modalities. However, significant challenges exist in imaging the gut using ultrasound, including the significant tissue motion, the presence of fat causing significant sound aberration and decreased image resolution. More recently we have been the first to demonstrate real-time super-resolution using of phase change nanodroplets.

In this project we propose to develop advanced ultrasound imaging, image analysis, and machine learning technologies for robust measurement of gut microvascular structure and function, and apply the technologies in the setting of gut inflammation, mucosal healing and measurement of gut response to drug treatment.

Strains on the healthcare system in the UK create an acute need for finding more effective, efficient, safe, and accurate non-invasive imaging solutions for clinical decision-making, both in terms of diagnosis and prognosis, and to reduce unnecessary treatment procedures and associated costs. Medical imaging is currently undergoing a step-change facilitated through the advent of artificial intelligence (AI) techniques, in particular deep learning and statistical machine learning, the development of targeted molecular imaging probes and novel "push-button" imaging techniques. There is also the availability of low-cost imaging solutions, creating unique opportunities to improve sensitivity and specificity of treatment options leading to better patient outcome, improved clinical workflow and healthcare economics. However, a skills gap exists between these disciplines which this CDT is aiming to fill.

Consistent with our vision for the CDT in Smart Medical Imaging to train the next generation of medical imaging scientists, we will engage with the key beneficiaries of the CDT: (1) PhD students & their supervisors; (2) patient groups & their carers; (3) clinicians & healthcare providers; (4) healthcare industries; and (5) the general public. We have identified the following areas of impact resulting from the operation of the CDT.

- Academic Impact: The proposed multidisciplinary training and skills development are designed to lead to an appreciation of clinical translation of technology and generating pathways to impact in the healthcare system. Impact will be measured in terms of our students' generation of knowledge, such as their research outputs, conference presentations, awards, software, patents, as well as successful career destinations to a wide range of sectors; as well as newly stimulated academic collaborations, and the positive effect these will have on their supervisors, their career progression and added value to their research group, and the universities as a whole in attracting new academic talent at all career levels.

- Economic Impact: Our students will have high employability in a wide range of sectors thanks to their broad interdisciplinary training, transferable skills sets and exposure to industry, international labs, and the hospital environment. Healthcare providers (e.g. the NHS) will gain access to new technologies that are more precise and cost-efficient, reducing patient treatment and monitoring costs. Relevant healthcare industries (from major companies to SMEs) will benefit and ultimately profit from collaborative research with high emphasis on clinical translation and validation, and from a unique cohort of newly skilled and multidisciplinary researchers who value and understand the role of industry in developing and applying novel imaging technologies to the entire patient pathway.

- Societal Impact: Patients and their professional carers will be the ultimate beneficiaries of the new imaging technologies created by our students, and by the emerging cohort of graduated medical imaging scientists and engineers who will have a strong emphasis on patient healthcare. This will have significant societal impact in terms of health and quality of life. Clinicians will benefit from new technologies aimed at enabling more robust, accurate, and precise diagnoses, treatment and follow-up monitoring. The general public will benefit from learning about new, cutting-edge medical imaging technology, and new talent will be drawn into STEM(M) professions as a consequence, further filling the current skills gap between healthcare provision and engineering.

We have developed detailed pathways to impact activities, coordinated by a dedicated Impact & Engagement Manager, that include impact training provision, translational activities with clinicians and patient groups, industry cooperation and entrepreneurship training, international collaboration and networks, and engagement with the General Public.