Transcranial Tissue Doppler Ultrasound for Emergency Assessment of Acquired Brain Injury

Background: Acquired brain injury (ABI) is known to be a leading cause of death worldwide. It is a challenging health issue for the patient and their relatives. Healthcare systems are increasingly required to deliver high-quality care for this population including early detection and continuous monitoring which could improve outcomes. Transcranial tissue Doppler (TCTD) is a new ultrasound technique used to measure brain tissue pulsations (BTPs). This technique has the potential to be applied in urgent care settings such as emergency departments (EDs) and prehospital care for early detection and screening as well as continuous monitoring of ABI patients.

Aim: The aim of this thesis is to explore the clinical potential and feasibility of using transcranial tissue Doppler (TCTD), by using a new prototype to identify patients with ABI.

Method: TCTD recordings were obtained using two different methods for both healthy individuals and patients diagnosed with ABI. Different quantitative and qualitative analysis plans were performed to test the reliability and clinical application of the TCTD technique.

Results: In this thesis, a systematic review is described, which summarises available ultrasound methods measuring BTPs. This was followed by development of a proposed checklist for identifying abnormal BTP waveforms, with a view identifying stroke patients when compared to age-matched non-stroke participants.

The new prototype was found to have good inter-observer reliability and excellent intraobserver agreement. In addition, significant changes in BTP amplitude were noted during recovery from hypocapnia, but not during the hyperventilation manoeuvre itself from 30 healthy participants. Finally, applying the new prototype in an urgent care setting showed no significant diagnostic capability for triaging patients with suspected ABI.

Conclusion: Measuring BTPs clinically using TCTD is feasible with some promise in diagnosing stroke patients, however, ABI did not appear to generate any clear diagnostic marks in BTP waveforms in an ED setting.