602 - Lecture 7, Chapter 6, Mid Term 2

Front 1

what is the last eye movement system to develop?

Back 1

vergence

Front 2

what system is most likely to have a dysfunction in the absence of disease.

Back 2

vergence

Front 3

what is the response time for vergence? I dont think this is the same as latency.

Back 3

1000msec

Front 4

vergence is driven by?

Back 4

retinal disparity and blur

Front 5

what is faster convergenc or divergence?

Back 5

convergence

Front 6

there are two vergence phases what are they

Back 6

initiation and completion

Front 7

what is the latency for vergence

Back 7

80 -160 msec when the pt is diplopic but responds in 200 msec to blur

Front 8

divergence insufficiency has what kind of AC/a ratio?

Back 8

low but is normal with basic eso

Front 9

an ac/a of ten goes with ce or ci

Back 9

ce

Front 10

what is the equation for calculating the ac/a via the clinical method?

Back 10

ac/a=(Dnear-Ddist)/accommodation in D

Front 11

what is the equation for calculating the ac/a via the lens gradient method?

Back 11

ac/a=(Dcc-Dsc)/power of the lens.

Front 12

what is the equation to calculate the ac/a via the heterophoria method?

Back 12

ac/a=PD(in cm)+(Dnear-Ddist)/accommodation in D

Front 13

what is the normal range for ac/a

Back 13

4-6

Front 14

insuficiancies are associated with what type of ac/a ratios

Back 14

low

Front 15

excess phorias are associated with what type of ac/a ratios?

Back 15

high

Front 16

in this class you treat high ac/a conditions with what?

Back 16

lenses

Front 17

a person comes in with a chief complaint of headaches with near work. this could be what kind of duane white syndrome

Back 17

ce

Front 18

to have CE you need three things what are they

Back 18

high eso at near
reduced NRC at near
high ac/a

Front 19

the second most common complaint related to duane white syndromes is a wandering eye (or intermittent exotropia) which euane white syndrome is this associated with?

Back 19

DE

Front 20

to diagnose DE you need three things what are they?

Back 20

high exo at far
reduced NRC
high ac/a

Front 21

what is the preferred way of treatment?

Back 21

overminus them or under plus

Front 22

if a person has a normal ac/a ratio but they are symptomatic what do you treat them with?

Back 22

prism

Front 23

the correct way to prescibe prism is to dissasociate and get the true phoria. true or false

Back 23

false that will give you too much, so do not use alternate cover test, verticle prism or the maddox rod

Front 24

the correct way in this class to treat CI is to do waht ?

Back 24

VT to increase the PRC

Front 25

to give a diagnosis of CI the pt needs what three things?

Back 25

high exo and near
reduced PRC at near
low ac/a

Front 26

wong says that CI can also be caused by pathology? waht are some examples

Back 26

parkinsons and progressive supranuclear palsy.

Front 27

lesion in what area of the brain causes CI.

Back 27

parietal or the nondominant cerebral hemisphere

Front 28

what is the least common of the duane whit syndromes?

Back 28

DI

Front 29

what three things must a pt have to be dx with DI?

Back 29

esophoria at far
reduced nrc at far
and a low ac/a (under 4/D)

Front 30

what is the tx of choice for DI?

Back 30

base out prism at far only

Front 31

what makes DI hard to treat with lenses or VT?

Back 31

the low ac/a ratio and the distance at which it happens.

Front 32

DI must be DDX from what?

Back 32

bilateral 6th nerve palsy
decompensated eso (same degree at near and dist)
decompensated monofixation eso

Front 33

DI is the initial sign of what syndrome?

Back 33

miller fisher sign

Front 34

possible causes of DI are?

Back 34

raised intracranial pressure, midbrain tumor, miller fisher (initial sign), diazapame intoxication, head trauma, intracranial hypotension, and cerebellar lesions.

Front 35

vergence is stimulated primarily by what? and also by?

Back 35

primarily by retinal disparity and also blur.

Front 36

vergence control takes place in what three areas?

Back 36

visual cortex, MST and the MST

Front 37

true or false there are motor neurons esclusively for vergence? if true where are they located?

Back 37

false there are no motor neurons just for vergence.

Front 38

true or false the striate cortex may be the beginging of vergence

Back 38

true

Front 39

the FEF sends signals to the ______ and then to the _________.

Back 39

first the FEF sends signals to the nucleus reticularis tegmenti pontis (NTRP) and then to the cerebellum specifically the dorsal vermis.

Front 40

what type of cells are know to be in the SOA?

Back 40

tonic and burst (some just sit in an soa meeting and some will burst out in anger)

Front 41

there must be more control in the horizontal or the vertical vergence nuclei?

Back 41

because the horizontal are more robust there must be more in the horizontal

Front 42

sub group c is located where and it innervates what?

Back 42

sub group c innervates the medial rectus and is located in the 3rd nerve nuclei.

Front 43

the dorsal vermis controls vergence at what distance?

Back 43

at far.

Front 44

when the dorsal vermis is damaged what kind of vergence problem do you see?

Back 44

basic eso, CE, or DI

Front 45

what cerebellar nucleus is in charge of near vergences

Back 45

te fastigial cerebellar nucleus.

Front 46

a leasion to the fastigial nucleus will lead to what?

Back 46

DE, CI and or basic exo

Front 47

a lesion to the NRTP leads to?

Back 47

impaired convergence so CI

Front 48

if you have a child that is already eso and you are going to cylco them will they get more eso or exo?

Back 48

eso

Front 49

what is the most common etiology of convergence spasm?

Back 49

functional which means that they don't have any dz beyond a crossed eye. (no major brain involvement)

Front 50

the congenital absence of sixth nerve nucleus results in what syndrome?

Back 50

duane retraction syndrome.

Front 51

convergence retraction nstagmus can be due to what type of tumor?

Back 51

pineal

Front 52

basically how does a pituitary tumor cause nystagmus problems

Back 52

the tumor is pressing on the tracts that are traveling to the cerebellum.

Front 53

what kind of nystagmus did we see with a pineal tumor?

Back 53

the child had convergence induced every time he looked up.

Front 54

true or false the SOA is in an proximity that could be damaged by surgery done on a pituitary adenoma?

Back 54

true.

Front 55

retraction nystagmus could also be caused by abberent regeneration of what nerve?

Back 55

3

Front 56

wht infectious condition can lead to joint pain, vertical gaze palsy and a slow nystagmus, with the VOR intact?

Back 56

whipple disease

Front 57

slow convergence oscillations can be seen in what disease?

Back 57

whipple disease

Front 58

what type of vergence can be used to reduce the amount of nystagmus?

Back 58

convergence

Front 59

INO is caused in between what two nuclei?

Back 59

CN 3 and CN 6

Front 60

is convergence intact with INO? yes or no what does this signify?

Back 60

yes so the this indicates that the vergence pathway avoids the mlf.