Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Neuroscience > Module 5: Visual Pathway > Flashcards

Module 5: Visual Pathway Flashcards

(70 cards)

Start Studying
0
Q

Examination of visual system

A

Visual acuity, Visual field, Pupillary light reflex, Extraocular muscles & Fundoscopy “VV PEF”

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

Anatomy of the visual pathway

A

Eye-optic nerve-chiasm-optic tract-lateral geniculate-optic radiation-occipital

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

To assess for macular degeneration

A

Retina

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

The optic nerve: etiology of dysfunction

A

Compression, inflammation, Infarction & Alterations in blood supply “CIAA”

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

Decussation of visual and pupil fibers. Multiple neighboring influences: ______, ______, ______ & ______.

A

Optic chiasm. CSF, Vascular, Skull & Pituitary.

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

In __________, the defects become homonymous, on the same side as the visual space. A ___________ localizes only to the retrochiasmal area.

A

Retrochiasmal lesions. Complete homonymous hemianopsia.

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

In retrochiasmal lesions, ________ are identical in size, shape and depth: applies only to _________. Imply a more _______: cortical anatomy.

A

Congruous lesions. Incomplete hemianopsia. Posterior lesion.

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

Lesion in congruous homonymous hemianopsia

A

Optic radiation

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

Lesion in incongruous homonymous hemianopsia

A

Optic tract

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

Retrochiasmal field defects: occipital lobe

A

Homonymous quadrant, Temporal crescent & Macular sparing “HTM”

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

Retrochiasmal field defects: lateral geniculate

A

Homonymous sectoranopia

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

Retrochiasmal field defects: temporal lobe

A

Homonymous “pie in the sky”

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

Carry fibers to the LGB. Carry pupil fibers to the midbrain enlage of _________ via the brachium of the superior colliculus. ________ field defects.

A

Edinger Westphal. Incongruous.

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

Located in the posterolateral thalamus. Retinotopic organization: layer _____ from contralateral eye. Layer ____ from ipsilateral eye. The _____ projects to 50% of the LGB.

A

Lateral geniculate. 1, 4 & 6. 2, 3 & 5. Fovea.

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

Meyer’s loop: temporal lobe. Parietal lobe path direct. Majority of fibers from other thalamic nuclei.

A

Optic radiations

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

Striate cortex V1. Caudal 50% encode central __ degrees. Middle 40% encodes ___ degrees. Rostral 10% encodes __ degrees. (The temporal crescent)

A

Occipital cortex. 10. 10-60. 60-90.

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

The where pathway

A

Occipitoparietal

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

The what pathway

A

Occipitotemporal

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

Testing techniques

A

Confrontation, Patient drawing & Bowl perimetry “CPB”

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

Bowl perimetry. Kinetic: ________.

A

Goldman perimeter

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

Bowl perimetry. Static: ________.

A

Humphrey perimeter

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

May occur unilateral or bilateral. Poor vision with small nerve. May occur in isolation or with ocular or forebrain abnormalities. When bilateral and accompanied by poor vision and nystagmus, usually other developmental abnormalities observed.

A

Optic nerve hypoplasia

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

Disturbance of axonal metabolism in the presence of a small scleral canal. Increase in size with time, more visible with time due to calcium deposition. Associated visual defect at times not noticed by the patients.

A

Optic disc drunsen

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

Possible association with increased abuse of alcohol and drugs. Phenytoin, quinine, alcohol, LSD and cocaine. Maternal diabetes. Perimetry: irregular borders, stable overtime.

A

Optic nerve hypoplasia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Central cup absent, anomalous vascular branching, vessels arising from the apex of the nerve, retention of vascular detail. Transillumination and irregular disc margin. No hemorrhage or cotton wool spots.
Disc drunsen (ophthalmoscope)
25
Causes are protean. Papilledema: elevated ICP and disc edema. Space occupying lesion. Disruption of axoplasmic flow at the level of the lamina cribrosa: fast and slow. Subsequent hypoxia and vascular changes on the disc. May take hours to resolve.
Swollen optic nerve
26
Elevated ICP: headache,nausea,TOV & tinnitus. Normal neurologic exam. Elevated CSF pressure with normal parameters & normal imaging to exclude mass lesion or dural sinus thrombosis. Transient obscurations of vision. Neck stiffness. Neck, shoulder or arm pain. Diplopia (CN VI palsy)
Idiopathic intracranial hypertension
27
Acquired optic nerve disease without disc edema. Painless progressive loss of vision over first week. Predominantly monocular. Preceding viral illness & sinus symptoms. Loss of acuity, abnormal visual field, color vision & afferent pupil defect.
Optic neuritis
28
Most common cause for disc swelling over age of 50.
Ischemic optic neuropathy.
29
Brings the target to the fovea
Saccades
30
Looking from far to near
Vergence
31
Moving objects are kept still on retina
Pursuit
32
When we move our head eyes stay locked on target
Vestibular ocular reflex
33
When image slips on a large portion of the retina
Optokinetic reflex
34
Adduction
Medial rectus
35
Elevation & small intorsion
Superior rectus
36
Intorsion & small depression
Superior oblique
37
Abduction
Lateral rectus
38
Depression & small extorsion
Inferior rectus
39
Extorsion & small elevation
Inferior oblique
40
Along the medial aspect of the eyeball, inserts at a point of 5.5mm of the limbus. It is controlled by oculomotor nerve. Contraction of this muscle causes adduction of the eye.
Medial rectus
41
Along the inferior aspect of the eyeball, inserts at a point of 6.5mm of the limbus. It is controlled by oculomotor nerve. When the eyeball is positioned 23 degrees ouward in the orbit with respect to primary gaze, contraction of this muscle causes depression of the eye. When the eyeball is postioned 67 degrees inward, causes excycloduction of the eye.
Inferior rectus
42
Contraction causes depression, excycloduction & adduction of eye
Inferior rectus
43
Along the lateral aspect of the eyeball, inserts at a point of 7mm of the limbus. It is controlled by abducens nerve. Contraction of this muscle causes abduction of the eye.
Lateral rectus
44
Along the superior aspect of the eyeball, inserts at a point of 7.5mm of the limbus. It is controlled by oculomotor nerve. Contraction of this muscle causes elevation, incycloduction & adduction of the eye.
Superior rectus
45
Passes through the trochlea and its insertion on the eyeball below the superior rectus muscle is at 51degrees with respect to primary gaze. Controlled by trochlear nerve. Contraction of this muscle causes incycloduction, depression and abduction of the eye.
Superior oblique
46
The insertion of the is on the eyeball below the lateral rectus muscle at 51degrees with respect to primary gaze. It is controlled by oculomotor nerve. Contraction of this muscle causes excycloduction, elevation and abduction of the eye.
Inferior oblique
47
Describes movement of one eye
Duction
48
Describes movement of two eyes in the same direction
Version
49
Describes movement of two eyes in opposite direction
Vergence
50
Point of intersection of line of sight when eyes are maximally converged. Theoretically, should be measured from center of rotation of eyes. Clinically, measured from the facial plane.
Near point of convergence
51
Maximun convergence ability or NPC is measured by
Confrontational testing
52
NPC breakpoint, target becomes double.
Greater than 7cm
53
Average NPC
5cm
54
The recovery point, target becomes single.
10cm
55
Fast, step-like eye movement that places image of the target on the fovea.
Saccade
56
Slow, smooth-following movement that maintains image of the target of fovea
Pursuit
57
The most common test for extraocular motility
Broad H test
58
Is also a part of confrontational testing
EOM testing
59
To investigate the integrity of EO muscles and their nerves. To assess the patient's ability to perform version eye movements. And to determine if strabismus is comitant.
Extraocular motility testing
60
A pursuit test done bonocularly with penlight at a test distance of 30-40cm. It tests 9 position of action, starting with primary position. It tests fields of action of the 6 extraocular muscles.
Broad H test
61
Direction where a particular muscle has the greatest action
Field of action
62
Look for lags or overshoots at various diagnostic position of gaze. Look for smooth and accurate pursuit movements. Look for any gaze restrictions or overactions of muscle in 9 position.
Broad H Test
63
When deviation of the visual axes remains constant in all fields of gaze, there is
Comitancy
64
When deviation of the visual axes changes with field of gaze, there is
Noncomitancy
65
Check by moving the target to diff. positions of gaze, while keeping the patient steady.
Comitancy
66
Expected findings for saccade testing
Smooth, Accurate, Full & Extensive. "SAFE"
67
Drugs, fatigue, basal ganglia syndromes, cerebellar syndromes, peripheral oculomotor weakness, white matter diseases and miscellaneous disorders.
Slow saccades
68
Calibration errors. Opsoclonus. Restriction syndromes.
Fast saccades
69
Ocular restriction syndromes. Cranial nerve, muscle palsies. Nuclear lesions.
Assymetrical saccidic velocity

Neuroscience (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions