Binocular vision 2: monocular fixation

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yes

Can the haidingers brush be used as a technique to train eccentric fixation

TRUE

T/F: eccentric fixation is only under monocular fixation

true

T/F: eccentric viewing is usually associated with an ocular disease condition

haidinger brush (MIT- macular integrity test)

_______ is a subjective test to evaluate EF. it uses rotating polarizers with a blue filter to make it easier to see

Brock-Givner Afterimage Transfer

_______ is a subjective test used to evaluate EF. an AI vertical flash is flashed in the non-amblyopic eye and is cortically transferred to the fovea of the amblyopic eye

retinomotor value

_______ is a value each photoreceptor has and is proportional to the distance from the fovea. This guides amplitude of saccades needed to fiat an object

visuoscopy

_______ is the most common method in evaluating EF. it uses the direct ophthalmoscope and uses the foveal light reflex if the patient has one (not all do)

eccentric fixation

_______ is using an eccentric point when fixating *MONOCULARLY*

eccentric viewing

_______ is when we train the patients or the patients have already done so, to use a non-foveal point for viewing

principle visual direction

________ is a monocular reference against which we compare all directions examples being oculocentric or secondary visual direction

maxwells spots

________ is a way to diagnose EF. it is pink spot seen at the macula when viewing a purple (blue and red mix) background. macular pigment selectively absorbs BLUE light

decreases

does increase in retinal eccentricity increase or decrease visual acuity

nasal and temporal

eccentric fixation is generally in the same direction as the strabismus (easy!) therefore ESOtropes have _______ EF therefore EXOtropes have ______ EF

unsteady and steady

eccentric fixation stability: _______ is more common and easier to treat because the patient is less adapted to EF ________ is less common and more challenging to treat because patient has adapted to new EF

20/x=1/EF+1

how can we use EF to determine the patients decrease in VA

eye, direction, magnitude, and stability

how do we describe eccentric fixation

fovea

in central fixation, the zero retinomotor value and the principle visual direction are both associated with the _______

normal correspondence

in order for the Brock-Givner Afterimage Transfer to properly work, the patient must have _________

one eye

is eccentric fixation one eye or two eyes

monocular (important to remember)

is visuoscopy monocular or binocular

4

it is important to note the magnitude of EF when using the haidingers brush; we have to remember that _____mm of EF at 40cm viewing distance is equivalent to 1pd

1

much like the haidingers brush, it is important to note the magnitude of EF during the Brock-Givner Afterimage Transfer test. we must remember that _____cm at 1m is equivalent to 1pd of EF

zero

normally the fovea has a ________ retinomotor value

VA and CT (monocular tests)

out of the following tests, which tests are affected by eccentric fixation; VA W4D CT stereo

fovea

the direction of eccentric fixation is relative to what structure in the eye

entopic phenomenon

the macular integrity test or the haidingers brush can view the ___________, basically radiating lines that resemble a propeller

temporal and nasal

visuoscopy: if the target is between the nerve and the fovea, the patient has ______EF if the target is outside the fovea, the patient has ______EF

maxwells spot and OCT

what are some other ways, other than the typical subjective and objective techniques, to evaluate/diagnose EF

VA, fixation, accommodation, and saccades

what are some specific amblyopic testing

CT/hirschberg (ocular alignment) and retinoscopy (RE)

what are some ways we can identify amblyopic factors

visuoscopy and HB/brock givner AI

what are the objective ways to evaluate EF what are the subjective ways

strabismic amblyopia

what kind of amblyopia is generally associated with eccentric VIEWING

unsteady (patching steady will reinforce EF)

what stability EF are we okay to patch, steady or unsteady?

eccentric localization

when both the zero retinomotor value and principle visual direction are associated with the eccentric fixation location, there is _______

location

when doing visuoscopy, do we determine the magnitude or the location of the EF first

fovea and eccentric viewing location

when the principle viewing direction is on the _______ and the zero retinomotor is on ________ then there is no eccentric localization


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