Brainscape's Knowledge GenomeTM

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


See full index

USAHS Neuroanatomy Test 3 > Syndromes, Cases, and Vision > Flashcards

Syndromes, Cases, and Vision Flashcards

1
Q

Hemicord Lesion/Brown-Sequard:

A
  • IPSILATERAL DCML & Motor Loss
  • CONTRALATERAL ALS (pain & temp) loss
  • Zone of Lessure - sprouting above and below lesion
    • EVERYTHING IPSILATERAL EXCEPT ALS**
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Transverse Cord Lesion:

A
  • Complete lesion
  • Everything below the lesion does not work
  • No sensory going up, No motor coming down
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Central Cord: (Small))

A
  • Affects anterior commissure (decussation site of ALS)

- Small: Bilateral suspended sensory loss pain & temp

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

Central Cord: (Large)

A
  • Affects anterior commissure (decussation site of ALS)
  • Large: More corticospinal involvement & DCML
  • *ANAL WINK**
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Posterior Cord

A
  • Loss of DCML

- Also ⅓ of your Blood supply is found here can be affected

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

Anterior Cord

A
  • Does Not affect DCML
  • AFFECTS ALS bilaterally
  • Hits some corticospinal tracts
  • ⅔ of blood supply is here can be affected
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Case 1: A 15-year-old high school wrestler was found lying supine on the mat after sustaining a hyperextension injury to his neck while drilling during practice, complaining of numbness, tingling, and a burning sensation in all 4 extremities. When the ambulance arrived, the patient was still complaining of numbness and tingling in all 4 extremities and was notably weak in motor function, especially in the upper extremities

A

Central Cord Syndrome

  • Paralysis/Muscle weakness (especially the arms)
  • Painful sensations (burning, tingling, dull ache)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Case 2: A 22 year-old snow skiing daredevil sustained an SCI while competing last weekend. He presents to your clinic with decreased ability to discriminate between hot and cold, and noticeable strength deficits throughout. His proprioception and ability to sense light touch are intact.

A

Anterior Cord Syndrome

  • ALS and motor symptoms
  • Other impaired sensations: Crude touch, Pain
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Case 3: A 60 year-old male presents to your clinic with decreased pain sensation in his LLE and decreased proprioception in his RLE. If you suspect a Brown-Sequard lesion, which LE would you expect to be weak? (MVA)

A

Right LE

  • DCML and motor pathways are affected on the same side
  • ALS affected on other side
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Eyes & Retina

A

Light enters lens & forms image on Retina (inverted/reversed)

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

Visual Field

A

Inferior VF → upper retina
Superior VF → lower retina
Right VF → left retina
Left VF → right retina

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

Fovea

A

Central Fixation Point in each eye

  • Looks like a “V” (highest point of visual acuity)
  • Surrounded by Macula
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Optic Disk

A

Formed by axons leaving retina and entering optic nerve

  • NO PHOTORECEPTORS
  • BLIND SPOT: 15* laterally & slightly inferior to central fixation point
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Outer/Back (layers of the retina)

A
  • Contains Photoreceptors
  • Rods: Good for low light, no color seen
  • Cones: In fovea & macula (High resolution, COLOR)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Bipolar Cells/Middle (layers of the retina)

A

-Receives input from photoreceptors & sends to ganglion cell layer

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

Ganglion Cells/Innermost (layers of the retina)

A

Parasol Cells: LARGE cell bodies & diameter
-GROSS MVMT/STIMULI
-Project to MAGNO layer of lateral geniculate nucleus (LGN)
Midget Cells: SMALL cell bodies & diameter
-FINE VISUAL DETAILS & COLORS
-Project to PARVO cell layers of LGN

17
Q

Optic Nerve

A
  • Input from retinal ganglion cells axon
  • Exit in Optic Canal
  • Enter visual field of R. eye on R. Optic Nerve
18
Q

Optic Chiasm

A
  • Where fibers cross (medial and nasal fibers)

- If damaged: TUNNEL VISION

19
Q

Optic Tract

A
  • Each carries info from IPSILATERAL retina of each eye
  • R. tract = info from L. visual field
  • L. Tract = Info from R. visual field
  • Damaged: Loss of vision in CONTRALATERAL FIELD
20
Q

Lateral Geniculate Nucleus (LGN):

A

-Carries info from different eyes by same hemiretina
6 Layers
-Parvocellular Layer: receives info from midget cells
-Magnocellular Layer: receives info from parasol cells

21
Q

Extrageniculate Pathways

A
  • A small number of fibers bypass the LGN to the Superior and Pretectal Areas
  • These fibers form the extrageniculate pathways
22
Q

Optic Radiations

A
  • Axons leaving LGN go to the primary visual cortex (PVC)
  • These fibers pass through parietal and temporal lobes
  • Lesion = Homonymous CONTRALATERAL visual field loss
  • Ex: R. Optic Radiation carry info from L. side
23
Q

Inferior Fibers (Meyers Loop)

A
  • Arch forward to TEMPORAL LOBE from LGN —>INFERIOR BANK of Calcarine Fissure
  • Carry info from inferior retina (superior VF)
  • Damage = PIE in the SKY
24
Q

Superior Fibers

A
  • Pass under PARIETAL LOBE → SUPERIOR BANK of Calcarine Fissure
  • Carry info from Sup. Retina (inferior VF)
  • Damage = PIE on Floor
25
Q

Upper & Lower Banks of Calcarine Fissure (Primary Visual Cortex)

A

Upper bank = cuneus (wedge)
Lower bank = lingula (tongue)

Sup. OR → Upper Bank
Inf. OR → Lower Bank

Retinotopically Organized
Fovea & Macula represented @ occipital pole

26
Q

Parallel Channels for analyzing motion, color, & forms (visual processing)

A

3 Channels

  • Motion (parasol → magno (LGN) → PVC → dorsolateral stream)
  • Form (midget cells → parvo (LGN) → PVC → ventral stream)
  • Colors (midget cells → parvo (LGN) → PVC → ventral stream)
27
Q

Dorsal Pathway (visual processing)

A

The “where” info

-To parieto-occipital association cortex

28
Q

Ventral Pathway (visual processing)

A

The “what we are looking at” info, SPECIFIC DETAILS

-Occipital-temporal association cortex

29
Q

Chart

A
30
Q

Opthalamic > Retinal > …

A

Superior (Inferior VF) or Inferior (Superior VF)

31
Q

Occlusion of Retinal Artery = Altitudinal Scatoma

A
  • Superior Retinal Artery Occlusion = Inferior Altitudinal Scotoma
  • Inferior Retinal Artery Occlusion = Superior Altitudinal Scotoma
32
Q

Amaurosis Fugax =

A

-Transient occlusion of Superior/Inferior branches of retinal artery
“Browning out”
-Lasts about 10 minutes (TIA of the eye)

33
Q

Monocular Vision Loss

A

Optic Nerve Damage

34
Q

Scatoma:

A

Damage w/in Retina

35
Q

Bitemporal Hemianopsa

A
  • Loss of lateral vision, both eyes
  • Damage to Optic Chiasm
  • Tunnel Vision
  • Loss of Temporal VF
36
Q

Contralateral Homonomous Hemianopsa

A
  • loss of L/R VF

- Entire OR’s, or Entire PVC, damage to Optic Tract, LGN, MCA stem, PCA, occipital lobe

37
Q

Contralateral Inferior Quadrantopia

A

Damage to Superior optic radiation or Superior bank of Calcarine fissure

38
Q

Contralateral Superior Quadrantopia:

A

Damage to inferior optic radiation or Inf. bank of Calcarine

USAHS Neuroanatomy Test 3 (6 decks)

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