Due to the ageing population the request for a change in healthcare delivery becomes inevitable. As people live longer the number of hospitalizations and clinical interventions rises. This upcoming increasing necessity for medical care is underlining the need for a cost...
Due to the ageing population the request for a change in healthcare delivery becomes inevitable. As people live longer the number of hospitalizations and clinical interventions rises. This upcoming increasing necessity for medical care is underlining the need for a cost effective change in healthcare delivery. Key items in this process of change are early disease detection, improved diagnostics and advanced therapy monitoring all by means of point-of-care functional imaging.
Within this context, the focus of the CVENT consortium is on the translation of photoacoustic imaging (PAI) from a research-based image modality to a low-cost portable multi wavelength combined PAI system for vulnerable plaque imaging. Cardiovascular disease (CVD), more specifically, vulnerable plaque rupture, remains the major cause of death for people at middle age. In the carotid arteries feeding the brain, vulnerable plaque rupture initiates cerebrovascular ischemic attacks. Consequently, there is a worldwide unmet and urgent clinical need for functional information to enable in-depth diagnosis of carotid plaque vulnerability, avoiding cardiovascular events (CVENT).
The CVENT project addresses this unmet clinical need for a diagnostic method to identify vulnerable carotid plaques. Vulnerable atherosclerotic carotid plaques, an age and lifestyle related vascular disease, remain a major cause of death for men and women at middle age and is also a hallmark of generalized CVD involving other critical vascular regions like the coronary arteries. Every patient exhibiting symptoms of partial occlusion of the carotid arteries is examined with US because a matured carotid plaque is potentially vulnerable to rupture. When that happens, the content of the lesion entering the blood stream can cause stroke. In the EU this affects over 1 million people annually. According to the guidelines, the patient will be operated, if a 70-99% occlusion of the artery is found. However, only one out of nine operations is effective (Barnett 1998; Rothwell 2003). Even worse, 19 operations need to be done to prevent a single stroke. Hence, the current method to assess plaque vulnerability is insufficient.
The main goal of the CVENT consortium is the development of a portable multi-wavelength PAI system with a hand-held PA/US probe for the assessment of plaque: composition and structure, size and shape, as well as mechanical properties. To achieve this goal the CVENT consortium will focus on the following ground-breaking interdisciplinary research and development objectives:
PAI system engineering to develop:
- Multi-wavelength diode laser beam sources with ultra-high pulse power short pulse duration.
- A highly efficient diode laser driver, allowing passive cooling of the hand-held probe.
- A multi-spectral diode-stack beam forming based on diffractive optical elements (DOE).
- A hybrid front-end for US and PA data beam-forming.
Advanced PAI signal processing to:
- Characterize and classify plaque by multi-wavelength PAI.
- Suppress clutter signals - by more than 10dB at the imaging depth of 3 cm that are superimposing the weaker PA signals by exploiting simultaneous US measurements, clutter spectral behaviour, and Doppler shifts of clutter from the flowing blood of large vessels.
- Improve PAI image quality by optimizing PAI/US hybrid reconstruction techniques.
PAI system verification and validation to:
- Verify the CVENT PAI system in vitro and ex vivo using human carotid plaques.
- Perform a first small clinical validation by imaging plaque prior to and during surgery.
These research and development objectives will be implemented in direct cooperation and interaction between clinicians, acting day-by-day in the related vascular medical field, system engineers and researchers on PAI signal processing, and product developers creating an efficient translation from research to verified and validated product development.
Now after month 18 in the CVENT project a great part of the objectives are implemented, tested and validations are starting. The pre-clinical validation will start with a small clinical study to investigate the feasibility of atherosclerotic plaque imaging using multispectral PAI. The clinical study will include 60 patients with a plaque in one of the carotids, scheduled for an endarterectomy procedure. Each subject will get a multi-wavelength photoacoustic examination of the carotid plaque.
In conclusion we can say that now in month 18 of the CVENT project:
- R&D is on track on all levels.
- The second prototype of PA/US probe, PAI research platform and high performance computing (HPC) framework are in use to perform 1) system tests, 2) in-vitro testing and 3) perform small pre-clinical and clinical studies.
- A full test in relation to performance of the PAI system and PA probes has been carried out.
- The pre-clinical studies to provide feedback for improvements will start soon.
- There is an excellent cooperation and interaction in the CVENT team.
- CVENT results have been presented towards the public and the scientific/industrial community at numerous occasions.
Cooperation is one of the success factors for project realization. Therefore, in CVENT great attention is given to: a) direct communication, b) open discussions between all levels and all disciplines, c) problem isolation, understanding and solving, d) exchange of PhD students and project members and e) regular meetings between the different partners to increase common knowledge and common understanding.
A cost-efficient point-of-care PAI system to provide functional information about carotid plaque vulnerability, is highly innovative and will give ESAOTE a global top position in the vascular market.
Moreover, the entire translational process of research/engineering towards clinical application will also generate exploitation opportunities on component level (ultra-high power short pulse diode lasers, DOE beam forming and highly efficient laser diode driver) for the industrial partners QUANTEL, SILIOS and BrightLoop. With an emphasis on a cost effective, multimodality PAI system for screening, diagnosis and monitoring of carotid plaque vulnerability using innovative (optical) technology, the CVENT research and development is fully dedicated to create a beyond state-of-the-art change in healthcare delivery.
More info: http://www.cvent-2020.eu.