Feasibility of integrated transcranial doppler ultrasound-near-infrared spectroscopy to measure cerebral haemodynamics in dementia, delirium, and depression (the VESPAR Project): A pilot study

BACKGROUND: Transcranial Doppler ultrasonography (TCD) and near-infrared spectroscopy (NIRS) are indirect measures of neurovascular coupling (NVC). No studies have assessed the feasibility of an integrated TCD-NIRS approach to measure NVC in patients with dementia, delirium, and depression. NEW METHOD: ) and deoxygenated (HbR) haemoglobin levels were measured. RESULTS: , HR, or prefrontal oxygenation. Participants with delirium were unable to complete the task-activated section of the protocol. All four tasks evoked indirect changes in NVC in healthy volunteers, and in patients with depression and dementia; only HbR differed in the depression group relative to the dementia group (p = 0.021). COMPARISON WITH EXISTING METHODS: While these techniques have been used individually in the different patient groups, they have not been used in conjunction to assess differences in NVC between all three groups. CONCLUSIONS: An integrated TCD-NIRS protocol in this pilot study was feasible in these patient groups to measure NVC, but not in delirium.