Signal Processing for Ultrasound Diagnosis of Cardiac Output
Lead Research Organisation:
CARDIFF UNIVERSITY
Department Name: Sch of Engineering
Abstract
EPSRC Portfolio: EPSRC Theme: Healthcare Technologies, Challenge: Optimising Treatment/ Optimising care through effective diagnosis, patient-specific prediction and evidence-based intervention, Research areas: Digital signal processing (grow)
Cardiac output is important for diagnosing shock and monitoring the patients' response to therapy at Emergency Departments, and could be measured using advanced non-invasive, stand-alone devices using Continuous Wave Doppler technology. However, despite the growing evidence that measuring cardiovascular haemodynamic parameters is directly linked to the prospects of the patients, monitoring is rarely administered as the procedure requires the involvement of highly-skilled medical professionals.
The procedure involves placing a small device in the suprasternal notch aiming directly down the longitudinal axis at the ascending aorta and across the aortic root. The device transmits continuous wave Doppler ultrasound signal, which is used to calculate the ejection velocity of the blood as it exits the aortic valve. Heart beat is also monitored. This approach, however, is often difficult in all but young and fit individuals, because of restricted and sometimes painful access to the suprasternal notch. For this reason, cardiac output via the pulmonary valve can generally be more conveniently monitored at the left parasternal edge if the device is placed directly anterior to the heart. This is a challenging procedure as it requires (i) accurate transducer and patient positioning, (ii) accurate transducer manipulation, hand movement and pressure control, (iii) abilities to recognise the appearance of the Doppler profile and optimise its characteristics, (iv) an understanding that each patient may need slight variation to the standard approach, and (v) an understanding that suboptimal appearances may occur with low flow states.
The proposed PhD project will contribute to developing a novel, low-cost, non-invasive robotic solution for fine positioning and adjustments of the ultrasound device that will enable the procedure to be administered by individuals with minimal training. This will enable timely and accurate diagnosis and repeated monitoring, therefore improving the choice and reducing the cost of any subsequent intervention, and increasing the likelihood of successful health outcomes.
The project will involve an investigation of how the method is administered in different clinical situations and variable body physique in order to gather experience and to collect required data for the robotic device. Advanced new signal processing algorithms will be developed for recognising the Doppler profile and providing feedback for automatic positioning of the ultrasound device in order to optimise its characteristics.
The positioning of the ultrasound device will be investigated in order to assess the blood flow through the pulmonary valve, and new advanced signal processing algorithms will be developed for recognising the Doppler profile and providing feedback for automatic positioning of the ultrasound device in order to optimise its characteristics. The PhD student will receive training in cross-disciplinary areas including signal processing, ultrasound and cardiac assessment and monitoring.
Cardiac output is important for diagnosing shock and monitoring the patients' response to therapy at Emergency Departments, and could be measured using advanced non-invasive, stand-alone devices using Continuous Wave Doppler technology. However, despite the growing evidence that measuring cardiovascular haemodynamic parameters is directly linked to the prospects of the patients, monitoring is rarely administered as the procedure requires the involvement of highly-skilled medical professionals.
The procedure involves placing a small device in the suprasternal notch aiming directly down the longitudinal axis at the ascending aorta and across the aortic root. The device transmits continuous wave Doppler ultrasound signal, which is used to calculate the ejection velocity of the blood as it exits the aortic valve. Heart beat is also monitored. This approach, however, is often difficult in all but young and fit individuals, because of restricted and sometimes painful access to the suprasternal notch. For this reason, cardiac output via the pulmonary valve can generally be more conveniently monitored at the left parasternal edge if the device is placed directly anterior to the heart. This is a challenging procedure as it requires (i) accurate transducer and patient positioning, (ii) accurate transducer manipulation, hand movement and pressure control, (iii) abilities to recognise the appearance of the Doppler profile and optimise its characteristics, (iv) an understanding that each patient may need slight variation to the standard approach, and (v) an understanding that suboptimal appearances may occur with low flow states.
The proposed PhD project will contribute to developing a novel, low-cost, non-invasive robotic solution for fine positioning and adjustments of the ultrasound device that will enable the procedure to be administered by individuals with minimal training. This will enable timely and accurate diagnosis and repeated monitoring, therefore improving the choice and reducing the cost of any subsequent intervention, and increasing the likelihood of successful health outcomes.
The project will involve an investigation of how the method is administered in different clinical situations and variable body physique in order to gather experience and to collect required data for the robotic device. Advanced new signal processing algorithms will be developed for recognising the Doppler profile and providing feedback for automatic positioning of the ultrasound device in order to optimise its characteristics.
The positioning of the ultrasound device will be investigated in order to assess the blood flow through the pulmonary valve, and new advanced signal processing algorithms will be developed for recognising the Doppler profile and providing feedback for automatic positioning of the ultrasound device in order to optimise its characteristics. The PhD student will receive training in cross-disciplinary areas including signal processing, ultrasound and cardiac assessment and monitoring.
Organisations
People |
ORCID iD |
Yulia Hicks (Primary Supervisor) | |
Jack Latham (Student) |
Studentship Projects
Project Reference | Relationship | Related To | Start | End | Student Name |
---|---|---|---|---|---|
EP/N509449/1 | 30/09/2016 | 29/09/2021 | |||
1804840 | Studentship | EP/N509449/1 | 30/09/2016 | 30/03/2020 | Jack Latham |
Description | - A stable envelope estimation method has been designed, which traces the shape of spectral content in Doppler ultrasound. - An efficient beat segmentation method has been designed,which separates Doppler ultrasound into individual cardiac cycles. - A variety of features and deep convolution neural networks, which previously have not been applied to Doppler ultrasound, have been shown to be useful for guiding measurements. |
Exploitation Route | The work has demonstrated several potential means of providing useful feedback for Doppler ultrasound. A large survey to increase data sets, and data types would be a logical next step, which would allow more generalisation of models, and evaluations to be performed. |
Sectors | Healthcare |
Title | Beat segmentation method |
Description | Means of segmenting Doppler ultrasound into individual cardiac cycles using the envelope shape, and spectral content of Doppler signals |
Type Of Material | Physiological assessment or outcome measure |
Year Produced | 2019 |
Provided To Others? | No |
Impact | Allows reliable feature extraction for individual cardiac cycles, for offline and real-time application. Allowing classification models to be designed, and implemented. |
Title | Maximum Frequency Envelope Estimation Method for Doppler Ultrasound |
Description | Novel image processing method for extracting the maximum frequency envelope associated with a Doppler ultrasound measurement. The maximum frequency envelope is a useful variable associated with Doppler ultrasound measurements, it can be used to monitor a number of clinical measures, such as cardiac output. |
Type Of Material | Physiological assessment or outcome measure |
Year Produced | 2018 |
Provided To Others? | No |
Impact | Easy application in research situations, robust in response to poor signal quality. |
Title | Doppler ultrasound measurements from suprasternal notch, for variety of scan qualities |
Description | Database of Doppler ultrasound measurements collected from healthy adult volunteers. |
Type Of Material | Database/Collection of data |
Year Produced | 2019 |
Provided To Others? | No |
Impact | Database will allow evaluation of features for prediction of scan quality/ ideal scan location, a has potential to for new models to be designed as an outcome. Models will provide feedback with respect to scan quality and scan location. |
Description | Open day demos |
Form Of Engagement Activity | Participation in an open day or visit at my research institution |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Public/other audiences |
Results and Impact | Presented a demo of ongoing work at open days to demonstrate potential projects future students could be involved with. |
Year(s) Of Engagement Activity | 2018 |
Description | Research Presentation |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Postgraduate students |
Results and Impact | Presentation detailing my ongoing work. |
Year(s) Of Engagement Activity | 2019 |
Description | Symposium and Poster presentations |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Postgraduate students |
Results and Impact | Oral and poster presentations detailing ongoing and completed work of postgraduate students and teams across universities. |
Year(s) Of Engagement Activity | 2017 |
Description | Symposium with Poster demonstration |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Postgraduate students |
Results and Impact | Symposium with oral and poster presentations, to spark debate and share ideas. |
Year(s) Of Engagement Activity | 2018 |
Description | University Conference |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Postgraduate students |
Results and Impact | University conference in which presentations were given detailing different research projects. Presentation competition detailing individuals works. |
Year(s) Of Engagement Activity | 2018 |