Week 1 - Lesson 3 (Part 3) Flashcards
What is the smaller and more medially located branch of the CCA?
The ECA
What does the ECA supply? (6)
- Neck
- Face
- Scalp
- Walls of the oral and nasal cavities
- Bones of the skull
- Dura mater
- not the orbit or the brain
What kind of flow pattern does the ECA have?
A highly resistive flow pattern
What does the highly resistive flow pattern of the ECA a result of?
The distal vascular bed that it supplies
What are the ECA branches? (8)
- Superior thyroid
- Ascending pharyngeal
- Lingual
- Facial
- in the carotid triangle - Occipital
- Posterior auricular
- Internal maxillary
- Superficial temporal arteries
What is the mnemonic device to help remember the ECA branches? (8)
Sally Ann Likes Flirting On Philidelphia's Main Street
What is the most inferior ECA branch?
The superior thyroid
What is the most superior ECA branch?
The superficial temporal arteries
What can the ECA branches act as when the ICA is severely stenosed or occluded?
Collateral pathway for blood flow to the brain
What are considered the most important ECA collaterals?
Those that communicate with the ophthalmic artery or the vertebral artery
What ECA collaterals communicate with the ophthalmic artery or the vertebral artery? (4)
- Occipital
- Facial
- Superficial temporal
- Internal maxillary arteries
Collateral flow
Re-routing blood flow
What arteries supply the brain? (2)
- Paired internal CCA
2. Paired vertebral arteries
What is the cervical segment of the ICA?
It is extra-cranial
- this is what we scan
How does the ICA course?
It usually courses quite straight in its
- occasional tortuosity
Where is the ICA directed? (3)
- Laterally
- Dorsally
- Upward in the neck
What kind of resistance does the ICA have?
Low
Why does the ICA have a low resistance flow pattern?
Because it supplies the brain
What are the normal variants of the ICA? (2)
- Coils
2. Kinks
How do coils become kinks for the ICA? (2)
- Aging
- High blood pressure
- this occurs overtime
What can kinks lead to?
Stenosis
What does the ICA mostly supply in the brain?
The anterior circulation of the brain
What is the ICA compared to the other branches of the CCA? (2)
- Larger
2. More lateral
What are the 4 portions of the ICA?
- Cervical portion
- extra-cranial - Petrous portion
- Cavernous portion
- Supraclinoid portion
Where does the petrous portion pass through?
Passes through this portion of the temporal bone
What is the cavernous portion also known as?
Siphon
- tortuous portion where the Ophthalmic artery branches
What happens in the supraclinoid portion?
Branching of the intracranial ICA occurs to form the circle of Willis
Where does the ICA run compared to the ECA?
Posteriorly
When does the cervical portion end?
When the vessel enters the carotid canal through the petrous bone
What does it become when the vessel enters the carotid canal through the petrous bone?
Petrous segment
What is the first intracranial branch?
Ophthalmic artery
What does the ophthalmic artery arise from?
The cavernous segment of the vessel
Where does the ICA terminate?
At the anterior cerebral artery
Where does the anterior cerebral artery arise from?
The supraclinoid portion of the vessel
What does the anterior cerebral artery supply?
The frontal lobes of the brain
