CVT 103 (Tristyn final notecards) Flashcards
2 planes
transverse: short axis
superior vs. inferior
medial is right of screen on the right side
medial is right of the screen
TGC
Time Gain compensation
controls gain @ different depths to compensate for loss of echo strength (attenuation) @ deeper structures
***Try to even out the gray scale throughout the field
Imaging:anatomy
Doppler: physiology
a
What does plaque look like on the duplex scan?
soft plaque: dark to medium echoes
calcific plaque: acoustic shadowing under plaque formation
First Branch off the ICA
opthalmic artery
ICA
Internal carotid artery
profuses eyes and brain
Larger than ECA
Lateral and posterior (posterolateral)
What 2 arteries are important for re-routing blood supply to brain and eyes if ICA is blocked?
Superficial temporal artery
and
facial arteries
First branch off ECA
superior thyroid
ECA
External carotid Artery
profuses face and scalp
smaller than ICA (contains branches)
medial and anterior (anteromedial)
Common Carotid
Arises off the aorta on the left, bifurcates on the right from the innominate
CCA turns into ICA and ECA @ about the level of the the laryngeal prominence (Adam’s apple)
*Brain is perfused by 2 carotids and 2 vertebral arteries
Opthalmic Arteries
Arise just proximal to the circle of willis
opthalmic artery is the first branch off the ICA
Endarterectomy
procedure to remove plaque deposits out of carotids
most common stroke causes
most strokes are caused by atheromatous plaque @ the carotid bifurcation
Sagittal
Long axis
Left vs. right
Transverse
short axis
superior vs inferior
distal (notch) of probe: towards right shoulder proximal probe: left
Medial is to the right on the right
medial is to the left on the left
How to learn probe ergonomics
Like learning a musical instrument: repitition!
program the neural pathways
Tension is noise in the system
DO not program tension!
Probe movements
Angling -sweeping across axis - left to right (sagittal) - up and down (transverse Rotating-turning around axis -turning around axis (sagittal and transverse) Rocking-rock along its axis -up and down (sagittal) -left to right for sagittal Sliding- move across skin -left to right in sagittal -up and down for transverse
Screen orientation in transverse
Look for the thyroid
top is superficial, bottom is deep
PT Right screen is Right Lateral, Left Medial
PT Left screen is Right for Medial, Left is Lateral
