Cerebrovascular autoregulation as a neuroimaging tool

Area of Science:

• Neuroscience
• Medical Imaging
• Physiology

Background:

• Functional transcranial Doppler (fTCD) sonography offers high temporal resolution for blood flow measurement, crucial for cerebrovascular disorders.
• Recent advancements allow non-invasive derivation of cerebrovascular autoregulation (CA) and cerebrovascular pressure reactivity (CR) indices.
• While fTCD excels in temporal resolution, its spatial localization is limited, hindering brain mapping.

Purpose of the Study:

• To review the functional transcranial Doppler (fTCD) technique.
• To emphasize cerebrovascular autoregulation (CA) and cerebrovascular pressure reactivity (CR) indices derived from fTCD.
• To explore the potential of coupling fTCD with functional MRI (fMRI) for enhanced brain function analysis.

Main Methods:

• Review of existing literature on fTCD, CA, and CR indices.
• Discussion of the principles and applications of fTCD in clinical settings.
• Exploration of the complementary strengths of fTCD (temporal resolution) and fMRI (spatial resolution).

Main Results:

• fTCD provides valuable dynamic blood flow information with excellent temporal resolution.
• CA and CR indices offer insights into brain's regulatory blood flow mechanisms in health and disease.
• The combination of fTCD and fMRI promises enhanced spatiotemporal resolution for brain imaging.

Conclusions:

• fTCD is a key tool for evaluating cerebrovascular disorders and brain regulatory mechanisms.
• The integration of fTCD with fMRI presents a promising avenue for advancing neuroimaging capabilities.
• Further research into combined fTCD-fMRI techniques can deepen our understanding of brain function and pathology.