B7.029 - Brain Stem and Cranial Nerves from Symptom to Lesion

Question 1

horizontal diplopia is a sign of what

Answer 1

either CN 3 or CN 6 issues

Question 2

describe the model of control of horizontal eye movements

Answer 2

starts with frontal eye fields –> fibers extend down to innervate Paramedian pontine reticular formation –> CN 6 carries that info to contralatera LR –> signal also splits off to abducens nucleus –> sends signal to medial longitudinal fasiculus –> cranial nerve 3 to synapse with oculomotor nucleus –> control of medial recuts etc.

Question 3

where does MLF extend to

Answer 3

cervical SC to mediate rotation of neck etc

Question 4

what is supranuclear

Answer 4

UMN problems associated with horizontal eye movement issues

Question 5

nuclear

Answer 5

issues with CN themselves

Question 6

internuclear

Answer 6

problem in horizontal eye movement pathway in MLF

Question 7

how do you tell if theres a problem inside or outside the midbrain

Answer 7

look for long track damage

Question 8

what does pupillomotor involvment in CN 3 lesion presentation tell you about possible localization

Answer 8

not much. it travels with other neves

Question 9

Answer 9

Question 10

biggest concern for extra axial CN 3 lesion

Answer 10

PCA aneurysm

Question 11

corticobulbar tract

Answer 11

connects UMN to innervate CNs

Question 12

UMN damage to corticobulbar tract

Answer 12

pseudobulbar palsy

Question 13

LMN tract damage to corticobulbar tract

Answer 13

bulbar palsy

Ambiguous nucleus

hypoglossal nucleus

solitary nucleus

medullary reticular formation

Question 14

Answer 14

medulla

Question 15

where does the SYM to the face/eye intersect with CNs X, 12

Answer 15

could be in brain stem or in jugular foramen

ascending SYM crawl along internal carotid artery

Question 16

Answer 16

Question 17

what is lateral medullary syndrome

Answer 17

Question 18

what can cause right lateral medullary syndrome

Answer 18

PICA occlusion

can happen with sudden turning of head (chiropractor)

or artery dissection/occlusion

Question 19

name the arteries and what syndrome the occlusion of the one pointed to can cause

Answer 19

lateral medullary syndrome

Question 20

Answer 20

Question 21

what is distict about stroke lesions

Answer 21

they respect the midline for the most part

Question 22

body weakness and cerebral cortex to motor nucleus lesion

Answer 22

UMN lesion

Question 23

facial weakness in cerebral cortexto motor nucleus lesion

Answer 23

central 7th

Question 24

eye movement affected in cerebral cortext to motor nucleus

Answer 24

supranuclear

Question 25

swallowing issues in cerebral cortex to motor nucleus

Answer 25

psudobulbar

Question 26

body weakness lesion between motor neuron to muscle

Answer 26

LMN lesion

Question 27

facial weakness from motor neuron to muscle

Answer 27

peripheral 7th

Question 28

eye movement issues from motor neuron to muscle

Answer 28

infranuclear

Question 29

swallowing issues from motor neuron to muscle

Answer 29

bulbar