Title: Randomised controlled trial investigating the role of a cloud-based, artificial intelligent image fusion system to guide endovascular aortic repair
Funder: Department of Health and Social Care

Abstract: Research question Can a novel type of medical device comprised of real-time cloud computing, AI and computer vision, improve the clinical and cost-effectiveness of X-ray guided surgery? Background X-ray fluoroscopy-guided surgery is a large and growing segment of the minimally-invasive surgery market, but is limited by 2D imaging that visualises soft tissues poorly. This poor visualisation contributes to imprecision and variable patient outcomes. Cydar EV uses computer vision to augment X-ray fluoroscopy imaging by fusing it with 3D soft tissue information from the patient s diagnostic CT scan with high accuracy and robustness. Pilot data from commercial test sites have shown Cydar EV is associated with reduced operating times and lower radiation exposure. Aims and Objectives This trial seeks to establish strong clinical evidence that Cydar EV reduces procedure duration, radiation exposure of patients and staff and is cost-effective. Methods Multi-centre, two-armed, randomised controlled trial of 322 patients with abdominal and/or thoraco-abdominal aortic disease undergoing endovascular repair using standard X-ray fluoroscopy imaging alone or augmented with Cydar-EV image fusion. The primary outcome measure is procedure time, and secondary outcome measures include radiation exposure, quality of life and technical success. Timelines for Delivery Open ten sites by months 9; recruit all patients by month 20; follow-up data by month 31; health economic analysis and submission of clinical, technical and cost-effectiveness data before end of month 36. Anticipated impact and dissemination Cydar EV is pioneering a new class of cloud digital products that promise to revolutionise the precision and consistency of patient outcomes. As a value-based subscription, they offer an alternative to high capital-expenditure procurement of imaging capabilities and clinical data insights. Establishing strong clinical evidence would accelerate adoption of Cydar EV for the benefit of patients, hospitals, and health services globally, as well as stimulating development of future products in this class.

Lay abstract: An aortic aneurysm is an abnormal swelling of the main artery of the body, the aorta. When the aneurysm reaches a certain size it can burst like a balloon. To prevent this a device called a stent-graft, which is a metal frame (stent) coated with a special fabric (graft) is introduced in a key-hole procedure called endovascular aortic surgery . Approximately 5,000 patients have this procedure each year in the UK, costing the NHS &pound;67.5 million. The stent-graft is designed for each patient before the operation using highly-detailed three-dimensional (3D) images but during the operation basic two-dimensional (2D) X-ray images are used to correctly position the stent-graft. We have developed state-of-the-art software that allows the 3D images to be joined with the 2D X-ray images in a process call 3D-2D image fusion . The surgeon then has all the benefits of the 3D information to perform the operation, which should make it easier. The difference between 2D X-ray and 3D-2D image fusion has been likened to the difference between watching a film in black and white (2D X-ray) and watching in 3D (3D-2D image fusion). The fusion software can be used on any X-ray system and can therefore be easily adopted across the NHS. We plan to undertake a study to compare 2D X-ray with 3D-2D image fusion. The study will involve 306 patients with an aortic aneurysm from 10 NHS hospitals across England and will last 3 years. We will explore if 3D-2D fusion makes the operation easier and therefore quicker, benefitting patients by reducing the amount of anaesthetic, harmful X-rays and dyes used during the procedure. We will also look at the financial benefits for the NHS. The results of the study are expected to inform national guidelines via NICE appraisal. We have consulted with ten members of the public (3 carers) and 10 patients with an aortic aneurysm (treated or awaiting treatment), recruited through NHS clinical practice. Face-to-face meetings and telephone conversations have helped shape the research question and the study protocol, for example by reducing the number of post-operative hospital visits by 30% to reduce patient burden. During the study two patient members will sit on the steering committee. They will help improve patient recruitment if needed, produce regular lay summaries for the study newsletter and help guide ethical decisions. Funding has been requested for patient members to attend and co-present the trial findings at the national meeting, with training in public speaking provided. The findings of the research will be presented on vascular society and trial websites, to which members of the public will have access. Engagement with clinicians will be via presentations and teaching at key vascular surgery conferences and via open access peer-reviewed scientific publications.

Research activity codes: 6.4 SURGERY
Health categories: CARDIOVASCULAR