NeuroSonology
Carotid US
- memorize velocities
- most important parameter is ICA PSV; the others are additional
> for results, described based on what parameter was used
- colors are related to flame: blue high velocity (turbulent flow)
Angle
- most appropriate is 60 degrees interfere velocities
Transcranial Doppler (TCD)
TCD-HIT study
-2 syringes: one w/ 8.5 ml NS, and 1.5 ml of blood and another empty
>Some places 1 ml of air and 1 ml of blood
-Agitation > 10 rapid exchanges until appears homogenous & bubbles
>Milky maneuver
-2 injections during valsalva & 2 not
>Valsalva 5s after injection and keep 10 seconds
*Hits often happen during the release phase when R-side pressure drops
HITS (High Intensity Transient Signals)
-Definition: unidirectional, <300ms, >3dB
-Record timing
<12s→ cardiac; >15s→ extracardiac (intrapulmonary)
-Spencer grading
TCD-HIT software
TCD wave-form
-all waves will have the same hallmarks
PSV, ESV, and MFV
MCA, ACA, PCA, Basilar
Pulsatility Index (PI)
-PI reflects distal vascular resistance (PI = (PSV − EDV) / MFV).
-PI > 1.3–1.5 suggests ↑ intracranial pressure or distal resistance.
-PI < 0.6 suggests low resistance, often hyperemia.
TCD-Patterns
