Cranial Nerves lll, lV, and Vl with vocab

Question 1

What is the primary function of the medial longitudinal fasciculus (MLF)?

Answer 1

coordinate eye movements

Question 2

A common lesion of the MLF could be caused by what disease that in turn affects CN lll, lV, and Vl?

Answer 2

MS

Question 3

With a lesion of the MLF the patient wont be able to laterally gaze but will have no abnormaility noted on convergence, why is this?

Answer 3

lateral gaze requires both CN lll and Vl whereas convergance only requires function of CN lll bilaterally

Question 4

What do the 2 separate supranuclear pathways for eye movement control?

1. Frontal Lobe =
2. Occipital Lobe =

Answer 4

1. Saccadic (rapid/darting) eye movement
2. smooth or following eye movements

Question 5

What is a nystagmus?

Answer 5

involuntary eye oscillations

Question 6

Disease of which CN will have parasympathetic manifestations such as eyelid ptosis and corectasia?

Answer 6

CN lll

Question 7

Disease of which CN will cause difficulty for the patient when looking down and in??

Answer 7

CN lV

Question 8

Disease of which CN will the cause the inability to laterally deviate the eye on the same side (ipsilateral) lesion?

Answer 8

CN Vl

Question 9

Disease of CN ll Will diminish what?

Answer 9

pupilloconstriction Bilaterally

Question 10

What would cause the pupil to be in fixed dialation?

Answer 10

Loss of diencephalon or midbrain function

(bilaterally would indicate patient is brain dead)

Question 11

What does paralysis of the superior tarsal muscle cause?

Answer 11

Ptosis

Question 12

What is cormiosis?

Answer 12

pupilloconstriction

Question 13

What does denervation of the sweat glands cause?

Answer 13

Facial anhydrosis (lack of sweating)

Question 14

What is a sympathetic hypofunction, often due to lesions of the neck proximal to the carotid artery bifurcation that compresses acending sympathetic fibers?

Answer 14

Horners syndrome

Question 15

What are the symptoms of Horner’s Syndrome?

Answer 15

1. ptosis
2. pupillo constriction (cormiosis)
3. Facial anhydrosis on the ipsilateral side of the head
4. Ipsilateral facial vasodialation

Question 16

Lesions along the sympathetic pathway distal to the bifurcation of the common carotid arteries will cause only what symptoms if occuring along the internal carotid pathway?

Answer 16

pupilloconstriction (cormiosis) and ptosis

Question 17

Lesions along the sympathetic pathway distal to the bifurcation of the common carotid arteries will cause only what symptoms if occuring along the external carotid pathway?

Answer 17

Vasodilation and anhydrosis

Question 18

What is Enophthalmos?

Answer 18

inward sinking of the eyeball and the eye socket

Question 19

What is a satisfactory way to assess sympathetic function in the head and face?

Answer 19

elicit the ciliospinal reflex

Question 20

What is the ciliospinal reflex

Answer 20

Pinching of the skin on the patients neck and observing for brisk BILATERAL pupillodilation

Question 21

Legal blindness is a __________ issue

Medical blindness is a failure to _________ _________ ___________

Answer 21

legal

perceive light stimulus

Question 22

What does confrontation test?

Answer 22

Peripheral vision

Question 23

What CN is thought to be the most notably conflicting with proprioceptive inputs when a nystagmus is present?

Answer 23

Vlll

Question 24

What is the Marcus-Gunn Phenomenon

Answer 24

apparent pupillodilation with light introduction

(pupil consticts less than the other pupil when introduced to the same light stimulis, no actual dialation) found with swinging flashlight test

Question 25

If the cup is greater than half the disc size what may this indicate specifically?

Answer 25

increased interocular pressure (glaucoma expected)

Question 26

What do the following findings indicate?

1. Blurred nerve fibers and cup
2. tortuous, engorged veins and loss of venous pulsations at dic margin
3. obliteration of physiological cup
4. disc elevation and edema

Answer 26

Papilledema (swelling of optic disc)

Question 27

What percent of the population has been described as having a pseudopapilledema and what ethnicity is MC?

Answer 27

5% (usually in blond caucasians)

Question 28

Inflammation of the optic nerve or disc has similar ophthalmoscopic characteristics to papilledema, how can you tell the difference?

Answer 28

papilledema wont have pain and is benign and usually self resolving

Question 29

If a fundiscopic exam inflammation appears to be behind the portion of the optic disc, the fundus looks normal but the patient has visual loss what is this called?

Answer 29

acute retrobulbar neurits

Question 30

Venous engorgement along with a light reflection off of the artery and may appear shiny (silver-wiring) may indicate what?

Answer 30

arteriosclerosis

Question 31

How can you evaluate the macula during a ophthalmascope exam?

Answer 31

have patient look directly into the light (insead of 15 degree angle towards the eye you took for evaluation of the other structures of the eye)

Question 32

What are a collection of degenerative deposits that often appear in the fundus of elderly people?

Answer 32

Drusen Bodies