Fossa La Vista
All the sutures and the landmarks where they meet from anterior to posterior of the skull
What are Frontal (Metopic), Coronal, Sagittal, Lambdoid, and Squamous sutures?
What are the Bregma, Lambda, and Pterion landmarks?
All the Cranial Nerves
Olfactory, Optic, Oculomotor, Trochlear, Trigeminal (Opthalmic, Maxillary, Mandibular), Abducens, Facial, Vestibulocochlear, Glossopharyngeal, Vagus, Accessory, Hypoglossal
Name all the branches coming off of the external carotid artery.
The muscles you use to crack a hard candy in your mouth.
masseter, temporalis, medial pterygoid
List four symptoms or signs of Horner’s Syndrome.
mild ptosis (drooping of the eyelid)
miosis (constricted pupil)
loss of heat-induced sweating
loss of heat-induced or emotional vasodilation (facial flushing)
All the major foramina through which neurovascular structures pass in the cranial fossae and skull base
Cribriform plate, optic canal, superior orbital fissure, foramen rotundum, foramen ovale, Foramen spinosum, carotid canal, internal acoustic meatus, jugular foramen, hypoglossal canal, stylomastoid foramen
These are the types of neurons whose cell bodies are located at the following ganglia:
a) geniculate
b) submandibular
c) trigeminal
d) ciliary
e) pterygopalatine
f) otic
g) stellate
a) [general/somatic sensory] taste sensory
b) postganglionic parasympathetic
c) general/somatic sensory
d) postganglionic parasympathetic
e) postganglionic parasympathetic
f) postganglionic parasympathetic
g) postganglionic sympathetic
Trace the pathway from the heart to the left lower lip.
heart--> ascending aorta -> aortic arch -> L common carotid a -> L external carotid a -> L facial a -> L inferior labial a -> left lower lip
These actions occur when a bolus of food enters the oropharynx during swallowing.
The soft palate is elevated by contraction of the levator veli palatini muscles, innervated by the Vagus (X)
The soft palate is made more rigid by contraction of the tensor veli palatini muscles, innervated by the mandibular division of the trigeminal (V3)
The posterior wall of the pharynx is brought closer to the soft palate by contraction of the superior pharyngeal constrictor, innervated by the Vagus (X)
A patient presents with unilateral Bell's palsy (on the left). List all symptoms you might expect.
Absence of wrinkling of the forehead
Drooping lower eyelid
Absence of nasolabial groove
Downturned mouth
Drooling
Sensitivity to loud sounds due to paralysis of stapedius
Metallic taste in mouth due to damage to chorda tympani
Define the anterior fontanelle and give three clinical reasons for palpating this area.
An area of unossified connective tissue on the top of an infant's skull where the coronal, sagittal, and metopic sutures meet.
a) bulge = increased intracranial pressure
b) sunken-in = dehydrated
c) disappears very early, or persists well past typical times of closure = disruption of the normal maturation process
These are the cranial nerves that supply preganglionic parasympathetic neurons, the branch that carries them, the ganglion that contains postganglionic parasympathetic cell bodies, and the branch of the trigeminal nerve that conveys them to the target structure.
a) Parotid gland
b) Mucosal gland in the lining of the hard palate
c) ciliary body and muscle
b) Facial nerve; greater petrosal nerve; (nerve of the pterygoid canal); pterygopalatine ganglion; greater palatine nerve
c) Oculomotor nerve; (inferior root of oculomotor nerve); (branch to ciliary ganglion); ciliary ganglion; short ciliary branches.
A front seat passenger in an automobile was hit from the side, causing their temple to bang into the side window. What type of intracranial hematoma is it, what's the cause of the bleeding, and between which layers does blood accumulate?
epidural hematoma
Skull fracture tearing the middle meningeal artery, resulting in bleeding into the space between the bones of the cranial vault and the outer layer of dura (endocranium) - the epidural space
The woman pictured to the left has undergone surgery to remove a tumor from her right submandibular gland. Following her recovery, she notices her mouth seems different. With reference to anatomy, explain what structure was likely damaged during the surgery and how this led to her current appearance.
The marginal mandibular nerve (or mandibular branch of facial nerve) was damaged. This resulted in paralysis of her right depressor labii inferioris which makes the right half of her lower lip more elevated than her left
There is a deep transverse cut across the scalp. What is the reason why you should get stitches, and what are two potential consequences related to anatomy in the region?
Deep transverse scalp wounds that go through the galea aponeurotica (epicranial aponeurosis) gap open because of the opposing pulls of the frontalis and occipitalis and must be stitched closed in order to heal.
Infectious material can enter the space deep to the galea (danger space), which does not contain anything that would prevent it from spreading over the entire surface of the cranial vault. Infectious material could enter the cranial cavity by passing through emissary foramina.
Craniosynostosis (brachycephaly)
The skull is short due to premature fusion of the coronal suture. It is broad and tall due to compensatory growth at the sagittal, squamosal and lambdoidal sutures
Right abducens nerve (CN VI) has been injured. This has resulted in paralysis of the right lateral rectus. The right medial rectus is therefore acting unopposed, pulling his right eye into adduction as shown in B. In order to avoid double vision, the patient turns his head to look at things in such a way that his adducted right eye will line up with his abducted (good) left eye, as in A
This condition leads to occasional dizziness and a fainting sensation. The blood pressure in the right arm is much lower than in the left. Duplex ultrasound reveals reversed blood flow in the right vertebral artery. Explain the anatomy and how it led to the reversed direction and neurological symptoms.
Subclavian steal syndrome
Stenosis in the very proximal part of her right subclavian artery diminishes blood flow into her right upper limb (low blood pressure). The diminished blood flow draws blood down through the right vertebral artery (reversal of direction of blood flow). The blood in the right vertebral artery comes from the basilar and the left vertebral artery. Thus, the right subclavian artery is "stealing" blood that is supposed to be supplying the brain, leading to the neurological symptoms
One morning, a man woke up looking like the photo (he is attempting to smile). What nerve has been damaged? Identify three features of his appearance that lead to this diagnosis. In each case, identify any paralyzed muscle.
left facial n (CN VII)
absence of wrinkling of the forehead - frontalis muscle; drooping lower eyelid/palpebral fissure too wide - orbicularis oculi; absence of nasolabial fold - zygomaticus major or levator labii superioris; drooping left corner of the mouth - zygomaticus major or orbicularis oris or levator labii superioris (any 3)
Young children seem very prone to developing middle ear infections, but eventually “grow out of it”. With reference to anatomy, explain why middle ear infections become less common as children become older.
Different proportions of the face and cranial vault in young children result in the auditory (Eustachian) tube being more nearly horizontal, which makes it easier for infections originating in the throat to travel to the middle ear. As the child grows up, the tube takes on the adult configuration of passing more inferiorly toward the nasopharynx, making it harder for infections to travel to the middle ear
The walls of the paranasal sinuses are coated with mucous membrane, and the mucus that is produced ultimately drains into the nasal cavity through various ostia (openings). Identify where the ostium of the maxillary air sinus is found, and explain, with reference to anatomy, why its location makes fluid drainage from this sinus problematic.
The ostium/opening for the maxillary air sinus is in a groove known as the hiatus semilunaris within the middle meatus. Since this opening is high above the floor of the sinus, gravity makes it difficult for fluid to drain when the head is in an upright position, which causes the maxillary air sinus to be prone to developing sinusitis
A neurological exam reveals that a patient has suffered a lesion to their right trochlear nerve. Among the observations confirming this diagnosis is that the patient habitually holds their head such that it is tilted to the left. Explain why the patient maintains this head position.
Lesion of the right trochlear nerve denervates the right superior oblique muscle. The superior oblique is an incycloductor and depressor of the eye. Loss of the resting tension in the superior oblique will cause the eye to take on an elevated and excycloducted position because the intact pull of the ipsilateral inferior oblique is unopposed. Tilting the head to the left will help alleviate the diplopia resulting from excycloduction of the eye.
Venous blood drains out of the skull through the internal jugular vein, the vertebral vein, and through a third route. Name this third route, and briefly explain its clinical significance.
The third route is the vertebral venous plexus, which has connections to dural venous sinuses (specifically, the occipital sinus and basilar plexus) that provide routes for infection or metastasis from elsewhere in the body to spread to the cranial cavity. (It can also take over for typical drainage through the IJV in those persons who must undergo radical neck dissection).
A 26-year-old female patient undergoes sternocleidomastoid myotomy for congenital muscular toricollis. After the surgery, the patient complains of difficulty in speaking and swallowing. A thorough examination reveals that she has nasal speech, absence of a gag reflex on the right pharyngeal wall, and an asymmetric soft palate. The surgeons hypothesize that the positioning of the endotracheal tube during surgery compressed the nerves that lie on the outer surface of the pharynx, resulting in the observed dysfunction. What nerve is it, and which 2 muscles are paralyzed as a result?
Vagus n. (CN X) (The direct pharyngeal branches have been compressed)
–Superior pharyngeal constrictor – constricts the superior part of the pharynx (thereby helping to close the space between the naso- and oropharynx)
–Levator veli palatini – elevates the soft palate (to close the space between the naso- and oropharynx)
What is the swinging flashlight test, and what are the results of the test shown in the picture? Explain which nerve has been damaged and give all three possible outcomes of the test.
right optic nerve(R CN II)
If both eyes are equal in their ability to perceive light and transmit this information to the brain, there will be no change in pupil size.
If the second eye perceives the light as dimmer than the first eye, or cannot fully transmit its information to the brain, then both pupils will dilate
If the second eye perceives the light as brighter than did the first eye (because the first eye has retinal disease), or more fully transmits its information to the brain (because the first eye has optic nerve disease), then both pupils will constrict.