Transcranial Doppler Ultrasound
Transcranial Doppler ultrasound (TCD) is used for evaluation of blood flow velocities in major brain arteries and vascular reserve in the brain. Blood flow in the brain is closely regulated to maintain relatively stable supply of blood to the brain during everyday activities. Regulation of blood flow distribution and vascular reserve in the brain is tested in response to changes in blood pressure and respiratory parameters. We developed novel- highly sensitive methods using nonlinear signal analysis ( Multi-modal Pressure Flow Method) for assessment of pressure-flow regulation. Diabetes, hypertension and stroke impair blood flow regulation, posing
a risk of low perfusion that may further affect brain function.
Tests
- Measurements of blood flow velocities in main arteries
- Cerebral autoregulation - measurement of beat-to-beat blood flow velocities in response to beat-to-beat changes in peripheral blood pressure
- Vascular reserve to CO2 and pressure autoregulation.
Instrumentation
- Power M-Mode transcranial Doppler technology (PMD-150), 2 channel, Spencer technologies Inc., Seatlle WA.
- Multi-DOP
X4, DWL Inc. for 4 channel recordings of cerebral/peripheral blood flow
velocities with 2MHz, 4 MHz and 8MHz and 12MHz probes.
