Head and Neck (General) Part 3 Flashcards
Internal Carotid Artery
Describe 3 characteristics
Name 4 branches
No branches in the neck.
Passes through carotid canal.
Passes through cavernous sinus.
Ophthalmic, posterior communicating, anterior, and middle cerebral arteries.
Common Carotid
What branch goes to skull?
What happens if it’s blocked.
Does this cause migraines?
Internal goes in skull.
Stroke!
Not associated with pain. May cause pressure behind eyes.
Anterior Cerebral Artery
3 facts including branches.
Pathology.
Smaller terminal branch
Anterior communicating branch joins the arteries.
Distribution–medial aspect of frontal and parietal lobes.
Not common but can occlude. Difficulty with decisions, and personality.
Middle Cerebral Artery
2 facts
Pathology
Larger terminal branch–supplies much of lateral aspect of brain.
Lots of strokes–memory (retrograde or forward amnesia), speech–may get scrambled.
Vertebral Arteries
What does it branch from?
Where does it enter skull?
Name 3 branches.
Branch from subclavian
Enter skull via foramen magnum
Anterior spinal
Posterior spinal (2)
Posterior inferior cerebellar–largest branch.
Basilar Artery
2 Where does it form?
4 branches
Formed from union of vertebral arteries.
Ends just rostral to pons. Rostral(top of brain).
Anterior inferior cerebellar.
Internal Auditory
Superior cerebellar
Posterior cerebral–terminal branches
Posterior Cerebral Art.
Where does it pass?
How is it distributed?
What happens if it is blocked? such as stroke.
Passes lateral to midbrain.
Distributed on medial surface of occipital and temporal lobes.
Affects vision. Everything functions fine, but it messes up brain interpretation.
Cerebral Arterial Circle. Name the 5 arteries that create it. What do the penetrating structures supply? Where is this circle? What is the purpose of these arteries?
Internal Carotid. Posterior Cerebral. Anterior Cerebral. Anterior Communicating. Posterior Communicating. Penetrating branches supply deep structures. Looks like the anterior pons. To supply the brain.
What nerve is encircled by the Cerebral Circle?
What happens if there is blockage in the cerebral circle?
Optic Nerve.
The optic nerve becomes blocked.
Cranial Nerves. How many pairs? What part of the nervous system do they belong to? CNS or PNS How do they get out? Where do they form?
12 pairs.
PNS
Pass through foramina or fissures in the cranial cavity.
They form on the brain or brainstem.
CN 1: Name Function Origin Foramen Destination What type of unique nerve cell are they?
The Olfactory N. Sensory (smell) in periphery. Olfactory epithelium (in nose) Olfactory foramina Olfactory bulbs.
CN II Name Function Origin Foramen Destination How many axons?
The Optic N Sensory (Vision) Retina in eye Optic Canal Diencephalon, then to occipital lobe. Over 1,000,000 axons.
Where is the diencephalon?
Thalamus
Hypothalamus
CN III Name Function and what specific muscles? Origin Foramen Destination
The Oculomotor N. Controls extra-ocular eye muscles (sup., inf, medial rectus, inf oblique, and Levator palpebrae superioris--eyelid) Mesencephalon (at brain) Superior orbital fissure Extra-ocular eye muscles.
What is the mesencephalon?
Midbrain
CN IV Name Function and muscle Origin Foramen Destination
Trochlear N. Controls extra-ocular eye muscles. (Sup oblique) (Rolls eye down and a little out) Mesencephalon Superior orbital fissure Extra-ocular eye muscles.
CN V
Name
Function and Divisions
Origin
Trigeminal N.
Mixed (sensory & Motor) function.
Opthalmic–Sensations from the forehead, eyelids, and nose.
Maxillary–Sensations from lower eyelid, upper lip, and cheek.
Mandibular–Controls mastication. (moving jaw up and down).
Origin: Ophthalmic, Maxillary, and Pons (Mandibular n.)
CN V
Foramen
Destination
Foramen: Opthalmic--Superior obital fissure Maxillary--Foramen rotundum. Mandibular--Foramen ovale (sensations of the face) Destination: Ophthalmic and maxillary: Pons Mandibular: Mandibular muscles.
CN VI Name Function and muscle Origin Foramen Destination
Abducens N Controls Eye Movements--Lateral rectus m. (abduct the eye) Pons Superior orbital fissure Innervates the lateral rectus eye muscle
CN VII Name Fucntions describe Origins Foramen Destinations
Facial N.
Mixed (sensory and motor)–Sensory: special smell/taste, Motor: muscles of facial expression
Origin: Sensroy: taste buds, Motor: Pons
Foramen: Internal acoustic meatus
Destination: Sensory: Pons, Motor: Muscles of the face.
