Exam 1 Review: Cerebrovascular & TCD

List the 3 branches of the aortic arch in order (R-L)

brachiocephalic-/innominate, left CCA, left subclavian

What arteries does the brachiocephalic/innominate artery branch off into?

right CCA and right subclavian

What arteries does the CCA bifurcate into?

ICA and ECA

The _____ provides primary blood supply to the brain. The ______ provides primary blood supply to the face and scalp.

ICA; ECA

Does the ICA typically have extracranial branches?

no

The ICA travels cephalad and terminates where?

Circle of Willis

What artery arises off the ICA?

ophthalmic artery

What segment of the ICA is #1?

cervical

What segment of the ICA is #2?

petrous

What segment of the ICA is #3?

cavernous

What are the 8 branches of the ECA?

1. superior thyroid

2. ascending pharyngeal

3. lingual

4. occipital

5. facial

6. posterior auricular

7. maxillary

8. superficial temporal

What type of flow does the ICA demonstrate?

low resistance

What type of flow does the ECA demonstrate?

high resistance

Left and right ____ and left and right _____ arteries continue up the neck into the base of the skull to eventually form an anastomotic ring known as the_________

ICA; vertebral; Circle of Willis

Where is the Circle of Willis located?

base of the brain

Label A

basilar artery

Label B

posterior cerebral artery (PCA)

Label C

middle cerebral artery (MCA)

Label D

anterior communicating artery

Label E

anterior cerebral artery (ACA)

Label F

distal ICA

Label G

posterior communicating artery

Label H

vertebral artery

What is transcranial Doppler (TCD) used to detect?

intracranial stenosis or occlusion

What probe frequency is used for TCD?

2 MHz

What is the assumed angle of insonation for TCD?

0

What are the 3 windows used in TCD?

1. transtemporal

2. transorbital

   1. transforamenal/suboccipital

What view is scanned with the transducer at #1?

transorbital

What view is scanned with the transducer at #2?

transtemporal

What view is scanned with the transducer at #3?

transforamenal/suboccipital

What TCD scanning approach is used for terminal ICA, MCA, ACA, PCA?

transtemporal

What TCD approach is used for ophthalmic?

transorbital

What TCD approach is used for distal vertebral and basilar?

transforamenal/suboccipital

Are the TCD scan approaches repeated on the contralateral side?

yes

In TCD, what are vessels identified based on?

depth and direction

What is normal PSV in the ICA?

<180 cm/s

What is PSV in an ICA that has <50% stenosis?

<180 cm/s

What is PSV of an ICA that has 50-69% stenosis?

180-230 cm/s

What is PSV of an ICA that has > or = 70% stenosis but less than near occlusion?

>230 cm/s

What is PSV of an ICA that is near occlusion?

high, low, or undetectable

What is the plaque estimate in a normal ICA?

none

What is the plaque estimate in an ICA that has <50% stenosis?

<50%

What is the plaque estimate in an ICA that has 50-69% stenosis?

>50%

What is the plaque estimate in an ICA that has >/= 70% but less than near occlusion stenosis?

>50%

What is the plaque estimate for an ICA that is near occlusion?

visible

What is the ICA/CCA ratio if there is no stenosis?

<2.0

What is the ICA/CCA ratio if there is <50% stenosis?

<2.0

What is the ICA/CCA ratio if there is 50-69% stenosis?

2.0-4.0

What is the ICA/CCA ratio if there is >/= 70% stenosis but not near occlusion?

>4.0

What is the ICA/CCA ratio if there is near occlusion?

variable

What is normal EDV of an ICA?

<40 cm/s

What is EDV of an ICA that has <50% stenosis?

<40 cm/s

What is EDV of an ICA that has 50-69% stenosis?

<100 cm/s

What is EDV of an ICA that has >/= 70% stenosis but not near occlusion?

>100 cm/s

What is EDV of an ICA that is near occlusion?

variable

What does total occlusion in the carotid artery look like?

no detectable PSV and no visible lumen