Dermatomes, reflexes, crainal nerves I

Question 1

What are some causes of Horner syndrome?

Answer 1

lesions above T1: Pancoast tumors, Brown-sequard above T1, advanced syringomyelia

Question 2

What dermatome levels do you need to know?

Answer 2

C2: posterior skull
T4: nipple
T7: xiphoid
T10: belly button
L1: inguinal ligament
L4 covers the kneecaps
S2,3,4: erection and sensation of penile and anal zones.

Question 3

Where do diaphragm and gallbladder pain radiate?

Answer 3

right shoulder via phrenic nerve

Question 4

Clinical reflexes nerve roots

Answer 4

Biceps: C5, (C6)
Triceps: C7 (C8)
Patellar L4 (L3)
Achilles S1, (S2)
count up: 1,2 buckle my shoe, L3,L4 kick the door, C5,C6 pick up sticks, C7, C8, lay them straight.

Question 5

What are the nerve roots that control the cremaster reflex and the anal wink reflex?

Answer 5

L1 and L2 do the cremaster reflex

S3 and S4 do anal wink

Question 6

What is Parinaud sydnrome?

Answer 6

paralysis of the conjugate verticle gaze due to lesion in the superior colliculi, which is responsible for conjugate verticle gaze.
pinealoma could cause this.

Question 7

Function of the trigeminal nerve, branches

Answer 7

branches: ophthalmic, maxillary, and mandibular

does mastication, facial sensation, and somatosensation of anterior 2/3 of tongue

Question 8

Functions of the facial nerve

Answer 8

facial movement, taste from 2/3 of tongue (geniculate nucleus), LACRIMATION, SALIVATION from submandibular and sublingual glands, eyelid closing via the ocularis oculi, stapedius muscle in ear

Question 9

What does glossopharygeal nerve do?

Answer 9

taste and somatosensation from posterior 1/3 of tongue, swallowing, SALVATION from parotid gland, monitoring carotid body sinus chemo and baroreceptors, and stylopharyngeous motor innervation

Question 10

What muscles are innervated by CNXI?

Answer 10

sternocleidomastoid and trapezius: head turning and shoulder shrugging

Question 11

What are the ganglia etc. involved with taste

Answer 11

CN VII: geniculate; 9 petrosal, X: nodose

Question 12

What are the ganglia etc. involved with CN parasympathetics?

Answer 12

III: Edinger-Westphal nucleus synapses in the ciliary ganglion
superior salivary nucleus of CN VII synapses on the pteryopalantine gangion, which controls lacrimation, and the submandibular ganglion, which controls salivation from the sublingual and submandibular area.
the Inferior salivary nucleus of CN IX synapses on the otic ganglion to control parotid salivation
The dorsal motor nucleus of CNX synapses on intramuerual ganglia.

Question 13

Where in the brainstem are the various cranial nerve nuclei located? How do you distinguish btw sensory and motor nuclei?

Answer 13

CN III and IV in midbrain
CN V, 6, 7 and 8 in pons
CN 9, 10 and 12 in medulla
CN 11 in the spinal cord
lateral are sensor, medial are motor

Question 14

What are the vagal nuclei? What other cranial nerves have cell bodies in these nuclei?

Answer 14

dorsal motor nucleus of CNX: parasympathetic motor nucleus
nucleus ambiguus: voluntary motor (palate elevation, pharynx, larynx, swallowing). Also involves IX, and some XI.
nucleus solitarious- taste info and visceral info (rostral is taste)