Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

equine Ophtho junior > Equine Ophtho exam > Flashcards

Equine Ophtho exam Flashcards

1
Q

Three basic layers of eye

A
  1. Outer coat (fibrous tunic)
    - cornea and sclera
  2. Middle layer (uvea)
    - choroid, ciliary body, iris
  3. central layer (nervous coat)
    - retina and optic nerve
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Choroid (4)

A
  1. located in posterior one half of eye (between outer sclera and retina)
  2. provides nourishment to retina
  3. modifies internal light reflection and scatter
  4. heavily pigmented or reflective
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Ciliary body (3)

A
  1. Production and outflow of aqueous humor through anterior segment
  2. Base for lenticular zonules
  3. muscles alter zonules to change lens shape
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Iris (2)

A
  1. Extends from ciliary body to anterior surface of lens

2. Changes shape of pupil

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

2 ophthalmic dzs in horses

A
  1. Ulcers

2. Everything else

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

Basic equipment (6)

A
  1. Pen/paper
  2. Eyeballs (mine)
  3. Drugs
  4. Dark room
  5. Bright light source (transilluminator)
  6. Magnification (Ophthalmoscope/jewelers loops)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Diagnostic tools (8)

A
  1. Culturettes
  2. Schirmers tear test strips
  3. Rose Bengal stain/or green stuff
  4. Fluorescein stain
  5. Topical anesthetic (Propericaine/Tetracaine)
  6. Blades, glass slides
  7. Catheter and syringe
  8. Tonometer - In an ideal world
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Therapeutic equipment (6)

A
  1. Subpalpebral lavage
  2. Syringes and needles
  3. Hard cup hood (Jorgenson eye saver cup)
  4. Fly mask
  5. Soft contact lens
  6. Drugs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How they see (4)

A
  1. Cornea lightly bends light
  2. Iris is the shutter
  3. Lens is fine focus (limited accommodation in horses)
  4. Retina - photo transduction
  5. No reds, better color percept in dim light than humans
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Critical aspects of equine vision (3)

A
  1. Wide panoramic view
    - 65 deg binocular (we have 120 deg)
    - 146 deg uniocular (we have 35 deg)
    - 3 deg blind spot behind (we have 170 deg)
  2. Good vision in low light
  3. Motion detection
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Equine acuity

A

20/33 - 20/60

-if horse has 20/50 and I have 20/20 horse needs to be at 20 feet to see what I can see at 50 feet

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

vision testing (2)

A
  1. Can test if completely blind

2. Cannot test vision objectively

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

Menace (5)

A
  1. Crude test
  2. Positive or negative (not degree vision)
  3. Positive = 20/20000
  4. Learned resp
  5. Subject and situation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Assessment limited to…. (3)

A
  1. Eye has dz/abnormality
  2. Visual deficit is present
  3. Major/vs minor - affecting behavior and safety
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Reflexes/responses (5)

A
  1. Menace - Foals older than 9 days (learned)
  2. PLRs - present at birth (subcortical)
  3. Dazzle - present at birth (subcortical)
  4. Palpebral
  5. Corneal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

PLR evaluates (5)

A
  1. Retina
  2. Optic nerve
  3. Midbrain
  4. Parasypathetic fibers of Oculomotor n.
  5. Iris musculature
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Optic pathway (5)

A
  1. Optic nerve ->
  2. Optic chiasm (crossing over) ->
    - lateral geniculate nucleus (stops)
    - Pretectal nucleus -> central decussation or PS nuc CN III
  3. Parasympathetic nucleus of CN III (Edinger Westphal nucleus) ->
  4. Oculomotor nerve CN III ->
  5. CIliary ganglia -> retina
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

PLR helpful in …

A

Prognosticating - Trauma and Ulcers

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

Visual with normal PLRs

A

YAY! You’re good to go

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

Visual with absent PLRs (3)

A
  1. Efferent problem (CN III or iris sphincter)
  2. Mechanical problem
  3. Drugs (Atropine)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Blind with normal PLRs (2)

A
  1. Something obscuring vision (cataract)

2. Cortical dz (behind reflex arc)

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

Blind with absent PLRs

A

99/100 retina or optic nerve prob

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

Example eye exam approach (8)

A
  1. Orbit
  2. Adnexa
  3. Tear film
  4. Cornea
  5. anterior chamber
  6. Uvea
  7. lens
  8. posterior seg
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

External eye exam (3)

A
  1. HX!!!!!!!!
  2. Menace, discomfort, d/c
  3. symmetry - orbit, globe position, eyelids/lashes, nictitans
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Ptosis (2)
Droopy lid 1. facial n. paralysis 2. horner's syndrome
26
Horners (5)
``` Interruption sympathetic nerve supply to eye 1. Sweating/ptosis Variable 2. enophthalmos, 3. TE prolapse 4. miosis, 5. +/-inc lacrimation...?!?! ```
27
Exam before sedation: Globe position/size (5)
1. Enopthalmos 2. Exophthalmos 3. Microphthalmos 4. Phthisis bulbi - shrunken, non-functional eye 5. Buphthalmos -GLAUCOMA
28
Exam before sedation: Orbit/Adnexa (2)
1. Position/symmetry | 2. Palpation/Retropulsion
29
Sedation drugs (4)
1. Xylazine 2. Detomidine 3. Butorphanol - head bobs 4. Romifidine
30
How to: Regional anesth (2)
1. 25 guage needle | 2. Lidocaine, Carbocaine, Bupivicaine
31
Motor blocks (3)
1. Facilitate exam 2. Facilitate procedure 3. Akinesia: CN 7-Auriculopalpebral
32
Sensory blocks (2)
1. Facilitates procedures | 2. Sensory Analgesia: CN 5 - frontal/supraorbital, line
33
Tear film (2)
1. STT - Quatitative/Not a linear/ <10mm/min = deficiency | 2. TBUT - Qualitative/Rose Bengal/green stuff < 10s = deficiency
34
Cornea exam (6)
1. Clarity 2. Color 3. Infiltrates 4. Integrity/defects 5. Presence/absence vessels 6. Thickness
35
Corneal Culture (5)
Aerobic/fungal 1. Culture PRIOR to putting stuff in 2. Ulcers with depth 3. Cellular infiltrate 4. Collagenolysis - melting 5. Severe edema
36
Cytology (4)
1. Gram stain, Wright-Giemsa, Diff-Quick 2. Bacteria, fungus 3. Inflammatory cells, neoplastic cells 4. Topical anesth, brush/blunt end of scalpel, edge of lesion
37
Indications to stain (4)
1. Redness 2. Pain 3. Cloudiness 4. Prior systemic/topical steroid use - FUNGUS
38
Fluorescein uses (4)
1. Corneal ulcers 2. TBUT 3. Seidel's test - aqueous leakage 4. Jone's test - NL patency (>10 min abnormal)
39
Rose Bengal stains (3)
1. devitalized cells 2. healthy cells not covered by tear film 3. NOT diagnostic for fungal infection - confirm with cytology or culture
40
Anterior segment eval
1. Bright light source and slit lamp (if poss) 2. AC 3. Iris
41
Aneterior chamber eval (6)
1. clarity 2. depth 3. mass lesions 4. hyphema - pooling of blood 5. hypopyon - WBCs 6. aqueous flare (ant uveitis) - inc protein and WBCs
42
Irirs eval (6)
1. Color/color changes 2. Position 3. Neovascularization 4. Pupil size 5. Infiltrates 6. Mass lesions
43
Miosis (2)
1. Hallmark CS of anterior uveitis | 2. Primary vs Secondary
44
Mydriasis (3)
1. Drug induced vs pathologic 2. Glaucoma 3. Retinal dz
45
Dyscoria (3)
1. Synechia 2. Uveitis 3. Mass lesions
46
Lens eval (4)
1. Need darkness 2. Transilluminate, retroilluminate 3. Clarity vs opacity - nuclear sclerosis or cataract 4. Position - subluxations or luxations
47
Iridocorneal angle
1. Open meshwork thru which AqH flows 2. Grossly visible in horses 3. Changes from inflammation, inc IOP
48
IOP
1. Tonopen vs tonovet 2. Use topical anesthetic and don't dilate yet 3. Head above heart 4. 16-30 mmHg is normal (higher than dogs)
49
Posterior segment of the eye
1. May need to dilate pupil 2. Direct ophthalmoscope/indirect/panoptic 3. US 4. Electroretinography 5. MRI
50
Pharmacologic mydriasis (3)
1. 1% Tropicamide - onset 10-20 min/duration 4-6 hours 2. 1% Atropine - onset depends/duration up to 14 days 3. 2.5% Phenylephrine
51
Vitreous (4)
1. If normal not visualized ush 2. Congenital abnormalities - persistnd hyaloid artery/remnant 3. Acquired opacities - transudates/exudates - Hemorrhage - Asteroid hyalosis - age related 4. Degeneration
52
Direct Ophthalmoscopy (3)
1. Ophthalmoscope 2. Small field - 10-15x magnified 3. Upright and real image
53
Indirect Ophthalmoscopy (3)
1. Transilluminator plus dioptic thing 2. Large field - 2-4x magnified 3. Upside down, backwards virtual image
54
Panoptic
1. Weird machine thing 2. Large field - 2-4x magnified 3. Upside down, backwards, virtual image
55
Settings on direct ophthalmoscope (6)
1. Light - spot size to 'just' fill pupil aperture 2. Slit - determ depression/elevation 3. Red-free (green) - observe opt nerve fiber layer and diff hemorrhage from pigment 4. Zero setting - observe fundus 5. Positive (green or black) - anterior 6. Negative - depression (back of eye)
56
Fundic exam (Retina) (7)
1. Position/integrity 2. anatomy 3. color 4. inflammatory lesions (active vs inactive) 5. Hemorrhages 6. Detachments 7. Tears
57
Fundic exam (Optic disk) (4)
1. Size 2. Shape 3. Color 4. Elevation/depression
58
Fundic exam (Vasculature) (4)
1. presence/absence 2. Number 3. Color 4. Tortuosity or attenuation
59
Tapetum resides in
superior choroid
60
Tapetum
1. Ush blue or green or yellow or absent
61
Non tapetum
1. black to brown | 2. various degrees of chorioretinal hypoplasia
62
Optic disk (5)
1. round to oval 2. salmon to pink 3. Myelin ush doesn't extend beyond ON 4. Located in nontapetal fundus 5. Vasculature visible on disc periphery
63
US findings (7)
1. Anterior seg mass 2. Cataract 3. Lens lux/capsule rupture 4. Vitreal debris/hemorrhage 5. Post segment mass 6. Retinal detach 7. Retrobulbar lesion
64
Rentinal vasculature pattern
Paurangiotic

equine Ophtho junior (14 decks)

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