Duplex CVR-2
Research type
Research Study
Full title
Validation and Optimisation of Cerebrovascular Reactivity Assessment with Carotid Duplex Ultrasound (Duplex CVR-2)
IRAS ID
316630
Contact name
Osian Llwyd
Contact email
Sponsor organisation
Research Governance, Ethics & Assurance
Duration of Study in the UK
3 years, 0 months, 1 days
Research summary
An ultrasound assessment is commonly used to assess the blood vessels in the head and the neck to determine how much blood is flowing through the vessel. Different breathing manoeuvres, such as holding your breath or breathing very quickly, can promote slight changes in the small blood vessels within the brain by making them larger or smaller. This helps the brain to regulate blood flow. However, this control system is susceptible to failure following an injury such as a stroke, when blood supply is prevented from reaching a part of the brain. Our previous work has shown that an ultrasound assessment on the neck can be performed when patients perform these breathing manoeuvres without affecting the quality of the data that is captured. This study will now determine if different assessments that promote changes in the blood flow to the brain demonstrate similar blood flow changes in the neck.
The first part (A) to the study will focus on determining the accuracy of using an ultrasound assessment to the neck to assess blood flow changes occurring in the head. Healthy individuals (n=20) and study participants who have had different stroke causes (n=60) will be asked to lie at rest and perform some breathing manoeuvres. They will also be fitted with a mask and be exposed to gases that make blood vessels larger. The second part to the study (B) will focus on optimising these assessments for patients (n=50) with abnormalities to small blood vessels in the brain; mainly by applying different gas concentrations and by altering the breathing manoeuvres. By getting some participants to repeat both parts to the study (A and B), the final part (C) will investigate how well these assessments are repeated. The outcomes of the studies will be to determine how closely related are the ultrasound assessments to the neck and head during such investigations and which test could be used during a routine clinical ultrasound scan to assess whether small blood vessels in the brain are working properly.REC name
London - Westminster Research Ethics Committee
REC reference
22/PR/1019
Date of REC Opinion
6 Sep 2022
REC opinion
Favourable Opinion