Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Vision Therapy > Optometric Terms 2 > Flashcards

Optometric Terms 2 Flashcards

1
Q

dynamic retinoscopy

A

retinoscopy performed while the patient fixates at near

term dynamic is used bc the patient’s accommodation is active

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

dynamic retinoscopy is in contrast to

A

static retinoscopy, which is done while the patient fixates at distance, where theoretically accommodation is relaxed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

eccentric fixation

A

in amblyopia, the condition in which under monocular viewing the amblyopic eye uses a point other than the fovea for straight-ahead viewing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

elevation

A

aiming the eyes upward

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

emmetropia

A

the condition under which an individual does not measure any refractive “error”

the patient sees well at distance without compensatory lenses, and sees blur when plus lenses are applied

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

enucleation

A

the surgical removal of the entire eye

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

esotropia

A

in strabismus, the condition in which one eye deviates inward while the other eye fixates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

excycloversion

A

rotation of the eye around the anterior/posterior axis toward the temple

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

exotropia

A

in strabismus, the condition in which one eye deviates outward while the other eye fixates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

extorsion

A

rotation temporalward

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

extra-ocular muscles

A

6 striated muscles that attach to the outside of each eye (total 12) and which allow the eye to move. these muscles coordinate together to produce eye movements in the different positions of gaze

lateral rectus, medial rectus, superior rectus, inferior rectus, inferior oblique, superior oblique

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

lateral rectus (LR)

A

abduction (away from the nose)

innervated by cranial nerve VI (the abducens)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

medial rectus (MR)

A

adduction (towards the nose)

innervated by cranial nerve III (oculo-motor)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

superior rectus (SR)

A

adduction, elevation, and intorsion

innervated by cranial nerve III

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

inferior rectus (IR)

A

adduction, depression, and extorsion

innervated by cranial nerve III

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

inferior oblique (IO)

A

abduction, elevation, and extorsion

innervated by cranial nerve III

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

superior oblique (SO)

A

abduction, depression, and intorsion

innervated by cranial nerve IV (trochlear)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

farpoint

A

the point upon which the visual axis of the eye is sharply imaged on the retina when accommodation is relaxed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

the far point of a “normal” eye is said to be at

A

optical infinity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

fixation

A

the process, condition, or act of directing the eye toward an object of regard, causing the image of the object to be aligned on the fovea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

in what sense is fixation an active process

A

during fixation there are small involuntary saccades, which are imperceptible to the naked eye

the oculomotor system sends and receives info to the brain in order to keep the image centered on the fovea, where it will best be seen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

fixation disparity

A

exists when there is a small misalignment of the eyes when viewing an object binocularly

since the corresponding points still fall within Panum’s areas, the object is still seen as single

the misalignment may be vertical, horizontal, or both

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

the misalignment in fixation disparity is measure in what?

how does it compare to misalignment in strabismus?

A

measured in minutes of arc

much smaller than that of a strabismus, although it may reduce a patient’s comfort and level of stereopsis

a patient may/may not have fixation disparity and a patient may have a different fixation disparity at distance than near

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

flipper

A

a lens carrier designed to hold two pairs of lenses such as plus lenses on one side and minus on the other, or base-in prisms on one side and base-out prisms on the other

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

fovea centralis

A

a tiny spot in the center of the macular area of the eye which enjoys a high concentration of cones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

visual acuity is said to be the sharpest at

A

the macula

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

the eyes move to position the images of objects of regard on …

A

on the fovea, as that is where they will be seen most clearly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

frontal lobe

A

sometimes referred to as the “executive” part of the brain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

functions of the frontal lobe (4)

A

involve the ability to recognize future consequences resulting from current actions

choose between good and bad actions (or better and best)

override and suppress unacceptable social responses

determine similarities and differences between things or events

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

the frontal lobes also play an important part in

A

retaining longer term memories which are not task-based (often associated with emotions derived from input from the brain’s limbic system)

the frontal lobe modifies those emotions to generally fit socially acceptable norms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

fusion and its 2 components

A

the unification of the individual images from each eye into a unified percept

sensory and motor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

sensory fusion

A

single, unified percept that results when corresponding retinal areas are stimulated by images of the same object or images of compatible content

the ability to appreciate two similar or compatible images, one with each eye and interpret them as one

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

for sensory fusion to occur, the images must be

A

located on corresponding retinal areas and also sufficiently similar in size, brightness, and sharpness

unequal images present a severe obstacle to fusion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

motor fusion

A

the physical movement of the eye to achieve a single image when presented with different retinal images to result in/ maintain sensory fusion

the ability to align the eyes in such a manner that sensory fusion can be maintained

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

the stimulus for fusional eye movements is

A

retinal disparity outside of Panum’s area and the eyes moving in opposite directions (mergence)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

sensori-motor fusion refers to the

A

quality and quantity of the binocular response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

grades of fusion

A

worth divided binocular vision into grades, relative to the type of demand presented by a target

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

first degree fusion

A

(superimposition) refers to the common localization of dissimilar but compatible images presented separately to each eye
ex: fish and bowl targets from mirror stereoscope (one eye sees fish other sees bowl, when fusion occurs, patient will see a fish in a bowl)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

second degree fusion

A

(flat fusion) refers to the single simultaneous perception of identical targets, one presented to each eye

upon examination of a second degree fusion target, the distance between all corresponding (homologous) points will be found to be the same

ex: AN 1 card used in the Brewster stereoscope

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

most second degree fusion targets include

A

a first degree fusion component that acts as a suppression control

41
Q

“fusion lock”

A

enhancing or guiding binocular posture and providing a “framework” for the simultaneous perception of the first degree fusion components

42
Q

third degree fusion

A

stereopsis, refers to the perception of depth when viewing targets that are designed with retinal disparity

43
Q

stereopsis

A

binocular appreciation of depth due to retinal disparity

44
Q

upon examination of a third degree fusion target

A

the distance between corresponding (homologous) points will vary, resulting in perception of depth when fusion occurs

although the distance between corresponding points varies, the differences are not great enough to prevent the entire target from being seen as single

45
Q

an example of third degree fusion target might be

A

clown vectogram

when the 2 films are super imposed the objects do not coincide exactly; this disparity is what vies rise to the perception of 3D when the appropriate fusion response is made

46
Q

hemianopsia

A

literally “half vision” a condition resulting from malfunction or damage to one side of the optic tract

47
Q

common causes of hemianopsia

A

stroke, trauma, and tumor

48
Q

hemianopsia can vary from

A

absolute loss of all vision on one side (light, form, and color) to a relative loss where vision is reduced, but not completely missing

relative heminaopsias may vary from light or motion detection only in the impaired field to subtle decreases sensitivity only demonstrate on careful visual field testing

the location of damage or lesion along the visual pathway determines the type of field loss

49
Q

binasal hemianopsia

A

vision is missing in the inner half of both the right and left visual fields

50
Q

bitemporal hemianopsia

A

vision is missing in the outer half of both right and left visual fields

51
Q

homonymous hemianopsia

A

loss of vision in the same visual field of both eyes

52
Q

Hering-Bielschowsky after image test

A

diagnostic test used to determine the status of correspondence between the eyes

53
Q

Hering’s Law of Equal Innervation

A

coordinated binocular eye movements require symmetrical innervation of the muscles of each eye

54
Q

versional movement

A

normally our eyes move together in the same direction, called versional movement

55
Q

Hering’s Law states that

A

yoke muscles receive equal innervation

56
Q

for example when looking to the left:

the left lateral rectus and right medial rectus muscles simultaneously contract

and the left medial rectus and right lateral rectus muscles relax

differentiate the two sets of yoke muscles

A

left lateral and right medial rectus muscles are yoke AGONIST (contracting) muscles

left medial and right lateral rectus muscles are yoke ANTAGONIST (extensor and flexor) muscles

57
Q

hippocampus

A

brain structure located inside the medial temporal lobe of the cerebral cortex

belongs to the limbic system and plays a major role in short term memory and spatial navigation

58
Q

in Alzheimer’s disease, the hippocampus is

A

one of the first regions of the brain to suffer damage,

memory problems and disorientation appear among the first symptoms

59
Q

damage to the hippocampus can also result from

A

oxygen starvation (anoxia), encephalitis, or medial temporal lobe epilepsy

60
Q

people with extensive hippocampal damage may experience

A

amnesia, inability to form or retain new memories

61
Q

Hirschberg test

A

screening test that can be used to detect the presence of strabismus

performed by shining a penlight in the person’s eyes and observing where the light reflects off the corneas

62
Q

in Hirschberg test, with normal ocular alignment the light lands on the center of both corneas

but in exo, eso, hyper, hypo…

A

exotropia the light lands on the medial aspect of the cornea

esotropia the light lands on the lateral aspect of the cornea

hypertrophic the light lands on the inferior aspect of the cornea

hypotonia the light lands on superior aspect of the cornea

63
Q

horopter

A

horizon of vision

the sum total of points in space which can be seen as single by the two eyes

defined as the locus of all points that are imaged on corresponding retinal elements at a given fixation distance

64
Q

a line can be drawn through the object of regard such that all the points on the line are imaged on the corresponding retinal elements and are seen singly. all the points not lying on the horopter are…

A

imaged by disparate retinal elements and are seen as double (diplopia elicited by object points off the horopter is called “physiological diplopia”

65
Q

hyperopia

A

also called farsightedness, the condition in which in the uncorrected eye, sight rays come to point focus behind the retina

66
Q

hyperopia is compensated for by the use of

A

plus lenses

67
Q

hyperphoria

A

the tendency of one eye to aim higher than the other

68
Q

hypertropia

A

in strabismus, the condition in which one eye deviates or aims upward, while the other eye fixates

69
Q

hypophoria

A

the tendency of one eye to aim lower than the other

70
Q

hypotropia

A

in strabismus, the condition in which one eye deviates or aims downward, while the other eye fixates

71
Q

incycloduction

A

the rotation of the eye around the anterior/posterior axis toward the nose

72
Q

intermittent

A

not constant

in strabismus the deviation is manifested irregularly, i.e. it is not always present (there are times and conditions when the eyes are aligned)

73
Q

intorsion

A

rotation nasalward

74
Q

iris

A

the colored tissue surrounding the pupil which is involved in regulating the amount of light that enters the eye

75
Q

isometropia

A

the condition in which both eyes have equal or nearly equal refractive status

76
Q

JND (just noticeable difference)

A

the smallest amount of change that can be made with the patient being aware of the change

the smaller the JND, the better the patient is at making fine discriminations

77
Q

Krimsky test

A

a test of binocular motor alignment by which a penlight is shone at the eyes and the position of the light reflect centered with a prism, thus indicating the amount of deviation

78
Q

lag of accommodation

A

when presented either with near targets or with minus lenses placed in front of the eyes, most individuals accommodate less than is needed to bring the target into focus

this under-accommodation is referred to as the lag of accommodation and is quantified by the difference between the actual accommodative stimulus and the measured accommodative response

79
Q

laterality

A

the individual’s ability to understand and identify right and left on his/her own body

80
Q

lateral geniculate nucleus (LGN)

A

one of the primary processing centers for visual info received from the retina of the eye

the LGN is located inside the thalamus of the brain

81
Q

where does LGN receive info from

A

receives info directly from the retinal ganglion cells via the optic nerve and from the reticular activating systems

82
Q

neurons of the LGN send their axons through the

A

optic radiations, a direct pathway to the primary visual cortex, also known as the striate cortex, in the occipital lobe

83
Q

LGN is where the process of … starts?

A

co-ordinating vision from the 2 eyes

it acts as sort of a “filter” determining what and how much info goes to visual cortex

84
Q

LGN receives many strong feedback connections from

A

the primary visual cortex

i.e. info travels in both directions

85
Q

localization

A

part of the process that helps the individual to identify the “where is it?” of objects in space

86
Q

lustre

A

(luster) refers to the appearance of 2 different colors, usually red and green, that when viewed simultaneously and superimposed, result in a mix of color, which is often unstable, and frequently described as “muddy brown” or “orange” and having a glossy or metallic quality

87
Q

macula

A

area in the back of the retina, located temporally and slightly below the optic nerve head

88
Q

what does the macula contain

A

fovea centralis

89
Q

macular integrity tester (MIT)

A

an instrument that provides feedback of the location in space where the fovea is aiming

useful in testing for and training eccentric fixation

90
Q

maddox rod

A

instrument used by the optometrist in measuring the alignment of the eyes

91
Q

minus

A

(concave) changes the path of light so that the focus is on the same side of the lens as is the object and closer to the lens than the object

makes objects of regard appear smaller and closer (SI of SILO)

92
Q

monocular cues to depth

A

cues that help us determine relative distances of things include:

1) apparent size
2) interposition
3) aerial perspective
4) shading
5) geometric perspective
6) relative velocity
7) motion parallax

93
Q

monocular cues to depth: apparent size

A

(small retinal objects are interpreted as distant objects and large as near); objects progressively increase in size as they move towards us (looming)

94
Q

monocular cues to depth: interposition

A

relatively nearer objects tend to conceal or overlay more distant objects

95
Q

monocular cues to depth: aerial perspective

A

water vapor, dust, and smoke in the atmosphere scatter light and make stint objects indistinct and relatively color desaturated

96
Q

monocular cues to depth: shading

A

light falling on solid objects causes shadows to be cast, and on curved surfaces causes a gradation in the intensity of shadow

97
Q

monocular cues to depth: geometric perspective

A

physically parallel lines converge toward a vanishing point at the horizon e.g. railroad tracks

98
Q

monocular cues to depth: relative velocity

A

image velocity of a moving target in the distance is lower than the image velocity of the same moving target when it is nearby

99
Q

monocular cues to depth: motion parallax

A

movement of the head cause the images of near objects to move opposite the head and the images of far objects to move with the head, assuming the fixation point is at an intermediate distance

Vision Therapy (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions