Equine Optho Flashcards
Entropion may lead to _____ or _____
corneal ulcer or perforation
If you catch entropion early in a foal, you can correct it by:
injecting saline where fold is.
Correction of entropion:
1.
2.
- simple interrupted sutures/mattress sutures.
2. Pinch skin, than use scissors to snip off a ellipsoid sliver of tissue and than place sutures.
Do you want suture tags from entropion correction to be short or long?
short, you don’t want them rubbing against eye.
Eye lid coloboma definition
a gap in the eyelid.
T/F:
Eye lid colobomas require quick treatment
F, they can be left alone if theyre not affecting the eye
Correct way to perform eye lid suturing for laceration:
- 1st thing to suture?
- 1st STITCH location?
- alternatively?
- Conjunctiva.
- edge between conjunctiva and skin
- figure eight knot to reduce irritation/dehisce.
Best way to remove SCC of eyelid?
Sliding flap technique
Name the layers of the cornea from the outside to inside:
Tear Film
Corneal epithelium
Corneal stroma
Descemet’s membrane
Endothelium
Keratitis definition
inflammation of cornea
T/F: There are no blood vessels in the normal cornea
True
Clinical symptoms of Keratitis:
1.
2.
3.
4.
- Blepharospasm
- Epiphora
- Corneal edema
- Cornea opacity
T/F: The fluorescein test does not stain the descemet’s membrane
True
How many layers of cells are in the corneal endothelium?
One! A single layer of cells
Steps of successful cornea healing:
1.
2.
3.
- Cell sliding
- Mitosis
- Normal epithelium achieved
Progression of complicated ulcer:
- Epithelial defect
2.
3.
4.
- Bacterial invasion
- Tissue destruction
- Corneal perforation
How does keratitis cause corneal opacity?
More fluid than normal in stromal area, causing collagen fibers to disorganize, no longer parallel and results in opacity
Cornea Vascularization:
Classification by vessel appearence:
- Very branched vessels =
- Anastamosis =
- Very straight =
- superficial
- superficial and deep
- deep
what gets stained during fluorescein testing?
Stroma
Catheter ends for eye medication:
- You want it placed where?
- why?
- In fornix
2. so it doesn’t irritate eye
T/F: You want to avoid cotton swabs during treatment of corneal ulcers
T. Cotton has enzymes that can mask infections.
How does a conjunctival pedicle flap work?
similar to a skin flap, you pull part of the conjunctiva forward to cover ulcer. Suture it to cornea. Bringing additional vasculature to that area for disposal of waste products.
3-4 months later remove the flap. Carefully trim it out
Stromal infection:
if you stain it with fluoroscein what happens?
there is no uptake of the fluoroscein.
If the flash test for stromal infection is irregular, what does it mean?
The epithelium is damaged
A laceration or a very deep infection that ruptures the anterior chamber can wash away the iris with the anterior chamber fluid out into the laceration. What is this called?
Staphyloma = iri prolapse
How do you treat Staphyloma
Carefully wedge/free the iris with a blunt tool ,than put in sutures. Place sutures first (without tying knot)
Best treatment for enophthalmitis?
Exenteration
Best treatment for lens luxation?
lens extration
A common sequelae after lens extraction is ____. Describe it
Pthisis bulbi. Eye shrinks in size.
4 Clinical features of equine recurent uveitis
- Uveitis
- Iridocyclitis
- Periotic ophthalmia
- Moon blindness
Equine Recurrent Uveitis
- % of horses affected?
- Breed prevalence?
- 12%
2. Appaloosas
Acute pain symptoms of ERU:
1.
2.
3.
- Photophobia
- Blepharospasm
- Lacrimation
Clinical symptoms associated with uveitis:
1. 2. 3. 4. 5.
- Conjunctivitis
- Edema/Vascularization of Cornea
- Hypopyon
- Miosis
- Posterior synechiae
Components of the uvea affected by uveitis
entire vascular tunic
Hypopyon definition:
leukocytic exudate
In posterior synechiae, ____ is attaching to ____
the posterior urface of the iris attaches to the anterior surface of the lens.
Describe the pathogenesis of posterior synechiae
Inflam byproducts act as glue. After acute phase we give atropine as a mydriatic, but the iris gets torn off because they are sticking to the lens
Best way to see posterior to cataract?
Ultrasound
4 main components for treatment of ERU
- Analgesics - Phenylbutazone
- Mydriatics -atropine/dark stall
- Topical corticosteroids (make sure there is no corneal ulcer)
- Surgery - vitrectomy
