Final: Ophthalmology

Question 1

What is the most common cause of miosis?

Answer 1

Uveitits

(other possibiltiy= corneal disease, or drugs)

Question 2

How are uveal cysts treated? Do they need to be treated?

Answer 2

Diode laser ablation

In horses they must be treated (impede vision)

Question 3

What are the Stars of Winslow?

Answer 3

End on capillaries of the choriocapillaris

Question 4

What does a steeper eyelash angle indicate?

Answer 4

Bleparospasm - PAIN

Question 5

How do you open the eyelids?

Answer 5

Index finger engages supraciliary sulcus

Sedation: xylazine, detomidine, torb, romifidine

Nerve blocks

Question 6

What are the 3 spots that you can block to obtain akinesia of the upper eyelid? What nerve are you blocking?

Answer 6

Caudal to posterior ramus of mandible

Dorsal to highest point of zygomatic arch

Zygomatic arch caudal to bony process of frontal bone

Auriculopalpebral nerve

Question 7

Where do you block the frontal nerve?

Answer 7

Supraorbital foramen

Blue in pic

Question 8

What can you do to overcome the challenge of having to use eyedrops in a horse? What is required to place this?

Answer 8

Place a Subpalpebral Lavage (SPL)

Sedation (detomidine +/- torb, topical AX (propara or teracane), nerve blocks (frontal and auriculopalp))

Question 9

What is the most common cause of blindness in horses? Which breeds are at-risk?

Answer 9

Equine recurrent uveitis (Moon blindness, periodic ophthalmia)

Appaloosas, Drafts, European warmbloods

Question 10

What is the most commonly implicated/suspected trigger for moon blindness?

Answer 10

Leptospirosis

Question 11

What clinical signs are seen in recurrent uveitis when the infection is acute and active?

Answer 11

Aqueous flare

Hypopyon

Fibrin (yellow hue)

Hyphema

Miosis

Iris hyperpigmentation

Question 12

What clinical signs are seen in recurrent uveitis when the infection is chronic and active?

Answer 12

Band keratopathy (mineral infiltrates into the cornea)

Glaucoma: episcleral injection, buphthalmos, corneal edema

Question 13

What are some scars of ERU that interfere with vision?

Answer 13

Posterior synecia

Cataract formation (blinding)

Phthisis bulbi (blinding)

Retinal degeneration/detachment (blinding)

Optic nerve degeneration

Question 14

What is the treatment plan for active ERU?

Answer 14

Systemic NSAIDs (Banamine, Phenybutazone, Aspirin)

Systemic corticosteroids (Prednisone, Dexamthasone - caution LAMINITIS )

Systemic antibiotics (Doxycyline- based on titer)

Topical steroids (Pred- C/O’d w/ CORNEAL DISEASE )

Topical NSAIDs (Flurbiprofen, Diclofenac)

Topical mydriatics (Atropine- caution COLIC)

Treat for at least 2 weeks post resulution

Question 15

What is the referral treatment option for ERU?

Answer 15

Cyclosporin implants

Effective for over 2 years

Question 16

What features in an examination suggest that a corneal ulcer is infected?

Answer 16

Deep ulcer

Diffuse corneal edema

Yellow-white corneal infiltrate

Keratomalacia/Melting

Deep corneal vascularixation (Crown of Thorns)

Severe reflex uveitis (miosis, aqueous flare hypopyon)

Question 17

What treatment is warrented for keratomalacia?

Answer 17

Agressive (q1-2 hrs) anticollagonase therapy

Autologous serum

EDTA

Acetylcysteine

Question 18

What are the most commonly identified organisms in infected equine ulcers?

Answer 18

Fungi:

• Aspergillus*
• Fusarium*
• Candida*

Bacteria:

• Pseudomonas aeruginosa*
• B-hemolytic streptococcus*

Question 19

What are the 2 diagnostic tests you should run for a corneal ulcer?

Answer 19

1. C&S (bacterial and fungal)
2. Corneal cytology

Question 20

What is the treatment for acute superficial non-infected (uncomplicated) corneal ulcers?

Answer 20

Topical broad spectrum antibiotics TID

Atropine

Systemic NSAID

Recheck 5-7 days

Question 21

What is the treatment for complicated corneal ulcers?

Answer 21

1. Topical broad-spec ABs: Triple antibiotic or Cefazolin (gr+) + Ofloxacin or Tobramycin (gr -)
2. Antifungals (Voriconazole)
3. Topical antiprotinase therapy (Serum)
4. Atropine q6-24 hours
5. Oral or IV NSAIDs (Banamine)
6. Subpalpebral lavage
7. Protective eye cup

Question 22

When should you consider referal for surgical repair of corneal ulcers? What is this surgeries?

Answer 22

>50% stromal depth

Rapidly progressive

Melting

No vascular response

Perforation

Sx: Conjunctival graft

Question 23

What clinical signs suggest the presence of a deep stomal abscess?

Answer 23

Fluorescein stain negative

Deep white corneal infiltrate

Corneal edema

Severe reflex uveitis

+/- vacularization

Question 24

How are deep stromal abscesses treated?

Answer 24

Aggresibe medical therapy!

Topical: Ofloxacin, Voriconazole (have good penetration), Atropine

Banamine

Question 25

When is surgery indicated for a deep stromal abscess? What are the surgical options?

Answer 25

If there is no clinical improvement after 24-48 hours of appropriate/aggressive medical therapy

Sx: Penetrating keratoplasty/ Corneal transplant, Intrastromal voriconazole inhection

Question 26

What are the 4 main predilection sites for SCC? What clinical signs indicate SCC in these locations?

Answer 26

Eyelid: hyperemic, erosive plaques, dark crusts, large fleshy mass

Conjunctiva/cornea/orbit: raised pink mass, Cobblestone appearance

Third eyelid/medial canthus: fleshy mass, erosions, crusts

Limbus (usually starts lateral) - UV exposure): fleshy mass

Question 27

What is the most important diagnostic recommendation with SCC?

Answer 27

Histopathology

Question 28

What are the treatment options for SCC?

Answer 28

Surgical excision (Enucleation, conjunctivectomy, third eyelid excision) + Adjunct therapy (cryo, CO2 laser…) + Lifelong monitoring

Communicate need for possible multiple treatments

Question 29

How is SCC prevented?

Answer 29

UV avoidance!

e.g. protective masks