sensory motor fusion eval Flashcards
what would you use to test sensory fusion (2nd degree) out of instrument (OIE)
worth dot/ red lens
what would you use to test sensory fusion (2nd degree) in instrument (IIE)
major amblyosope
what would you use to test motor fusion OIE
prism bar, risley prism
what would you use to test motor fusion IIE
major amblyoscope
what would you use to test (amomalous)
PAT and PPAT
what are 2 important aspects of suppression
-occurs only on simultaneous stimulation of both eyes (binocular phenomenon) and attributed to cortical inhibition
describe the 3 sizes of suppression
-foveal (< 1)
-central (1-5)
-peripheral (> 5)
(in degrees)
on worth 4 dot, what suppression size are you testing on near vs. far
near= peripheral distance= central
what aspects of a strabismus are correlated with suppression
depth of suppression related to frequency of strab.
so constant strabs more likely to suppress and have deep suppression
how is the size of a strabismus related to suppression?
doesn’t correlate
intensity of suppression has no relation to >D size of strabismus
list factors related to increasing dissociation from more natural to less natural
free space -> in-instrument -> polaroid filters -> red filter -> red green filter
how you define shallow suppression
only under natural conditions (easy to elicit diplopia with less natural testing conditions)
define deep suppression
present under most/all viewing conditions
where is the “zone of suppression” and what does it look like in the classical view (Jampoksky)
- between fovea and point Z
- “D” shaped scotoma that is greater in horizontal than vertical
according to the classical view (Jampoksky) of suppression, where would the suppression zone be in ET?
nasal hemiretina
according to the classical view (Jampoksky) of suppression, where would the suppression zone be in XT?
temporal hemiretina
how does the Pratt-Johnson theory of suppression work?
- binocular “field of vision”
- suppress entire area of VF of deviated eye that corresponds with fixating eye
what is the key point to the Pratt-Johnson theory of suppression
-suppress BOTH nasal and temporal areas of retina that overlap fixating eye, temporal crescents not suppressed
for Pratt-Johnson theory of suppression, what is the binocular “field of vision” for ETs vs. XTs
ETs: smaller
XTs: larger
what is a difference in the “hemiretinal” part of the Pratt-Johnson theory of suppression
-did not find hemiretinal suppression, but did find “hemiretinal trigger” for suppression and diplopia
if image falls on nasal retina of ET patient, then what occurs
“hemiretinal trigger” for suppression
if image falls on opposite side of fovea (overcorrection with prism or from surgery), then what occurs
“hemiretinal trigger” for diplopia across whole overlaying retinal areas
