Eye Lecture Review Flashcards
What are a few diseases involving the accessory structures of the eye?
Conjunctivitis
Epiphora
Keratoconjunctivitis sicca (KCS)
“Cherry eye”
What are a few diseases within the globe of the eye?
Corneal ulcers
Cataracts
Glaucoma
Uvetits
Trauma
What are a few diseases involving the retina and neural pathways of the eye?
Progressive Retinal Atrophy
Retinal Hypertension (secondary to systemic disease)
What are some accessory structures of the eye?
AKA the “adnexa”
Eyelids
Tear ducts
Third Eyelid
Lacrimal Glands
What are some clinical signs of conjunctivitis?
Chemosis
Hyperemia
Ocular Discharge
+/- signs of upper respiratory tract disease
What are the difference in conjunctivitis in dogs and cats?
Dogs: Typically non-infectious (Immune-medicated, Allergic, Anatomic (entropion, dystechia))
Cats: Typically infectious (Viral: Feline Herpes Virus, Calicivirus; Bacterial: Chlamydia psittaci, Mycoplasma)
What is epiphora and what causes it?
Overproduction of tears; Secondary to injury/trauma such as entropion, ocular injury, and dystechia. Faulty drainage of the lacrimal duct cause also be a cause.
What is the medical term for dry eye and what does it mean?
Keratoconjunctivitis sicca (KCS) means inflammation of the cornea and surrounding tissues from drying
What is the best test for KCS or dry eye? What are the normal ranges for this test?
Schirmer tear test(STT). This simple test uses a special wicking paper to measure the amount of tear film produced in one minute
Normal STT is 20 +/- 5
What is blepharospam and blepharitis?
excessive blinking of the eyelids and inflammation/swelling of the eyelids
What are the three forms of entropion?
- Congenital (inherited)
- Acquired non-spastic
- Acquired spastic
What is entropion? What is ectropion?
Inward turned eyelids and outwardly turned eyelids
What is the treatment of entropion and ectroprion?
Surgical correction
What is cherry eye?
HYPERTROPHY OF THE NICTITATING MEMBRANE (THIRD EYELID)
What is the correct treatment for cherry eye?
Surgical correction using the tack-down or pocket technique - DO NOT REMOVE THE GLAND
What is glaucoma?
Increased intraocular pressure
What is IOP and what are the normal ranges?
Intraocular pressure and 20 +/- 5 mmHg
What are the two primary ways glaucoma effects the eyes?
Pain and Vision Loss
What is acute glaucoma?
Sudden IOP >60 mm Hg that can produce blindness within hours
The goal is to rapidly reduce IOP to prevent permanent injury
THIS IS A TRUE EMERGENCY
How is IOP measured?
Tonometry
Is there a perfect solution for glaucoma?
No, this disease is a life long battle. Opening the drain to release the pressure is a difficult avenue for pets so most therapies aim at decreasing the fluid production
What are the treatments for acute glaucoma? Chronic?
Topical, oral and intravenous medications. Surgery can also be considered; Surgery is the main corrective function of chronic glaucoma
What is the medical term for corneal ulcers?
Ulcerative keratitis
What is ulcerative keratitis? List a few of the potential causes?
A full thickness loss of corneal epithelium that exposes the stroma;
Trauma
Chemicals
Foreign bodies
Diseases (KCS)
Dystechia
Herpes viral infections (cats)
What is one of the most common cause of ocular disease in the horse?
Corneal Ulcers
What are the treatments for corneal ulcers?
Topical (NO STEROIDS)
SPL often placed in horses
Surgery
What are the clinical signs and diagnostic test of choice for corneal ulcers?
Epiphora, Blepharospasm, Hyperemia of conjunctiva; Fluorescein Stain
Why are steroids not recommended for Ulcerative Keratitis and with multiple medications how long should you wait between applications?
Steroids will slow the healing process and may make the ulcer worse; 5 minutes.
What is Pannus?
An immune mediated corneal disease primarily found in the German Shepherd breed although other predisposed breeds include Greyhounds, Huskies, and Dachshunds
What is the diagnostic method for Pannus?
Corneal scraping w/ cytology revealing lymphocytic-plasmocytic inflammation
What is the treatment for Pannus?
Life-long anti-inflammatory agents
Cyclosporine
1% Prednisone Acetate
0.1% Dexamethasone
There is no cure
What is a cataract?
Any opacity within a lens.
What are the three types of cataracts?
- Very small (incipient cataract) and not interfere with vision.
- Involve more of the lens (immature cataract) and cause blurred vision.
- Entire lens can become cloudy (mature cataract) and all functional vision lost
What is the etiology of cataracts?
It can be inherited or secondary to disease with Diabetes mellitus being a common culprit
Is there treatment for cataracts?
Yes, to have them surgically removed.
What is uvea and what are the 3 parts of it?
the pigmented layer of the eye, lying beneath the sclera and cornea, and comprising the iris, choroid, and ciliary body
What are the iris, choroid and ciliary?
The iris: controls the diameter and size of the pupils and thus the amount of light reaching the retina
The choroid: the layer of blood vessels and connective tissue
The ciliary body: part of the eye that includes theciliarymuscle, which controls the shape of the lens
What are the clinical signs of Anterior Uveitis and how is it primarily diagnosed?
-Decreased IOP, Episcleral injection, epiphora, conjunctivitis. Prolapsed 3rd eyelid, pain, change in color of iris
-Tonometry with IOP <4-8mm Hg
What is the treatment for Anterior Uveitis?
Tx underlying cause
Topical anti-inflammatory agents (Furbiprofen, Dexamethasone)
What is Moon Blindness and what species is this seen in?
Recurrent uveitis in horses
What is the treatment for recurrent uveitis and what is something you must be mindful of with one of the treatments?
Topical anti-inflammatory drops, atropine. - Atropine may cause colic when used long-term
What is an infection of the external ear canal?
Otitis Externa
What is the etiology and diagnostic testing for Otitis Externa?
bacteria, yeast, parasites, FB, polyps
Dx: exam, cytology, +/- C&S
What is the treatment of otitis externa?
Topical(aural) or oral medications. Routine cleaning and good hygiene habits are needed for preventative measures as well
What is a collection of blood within the cartilage of the ear and the skin?
Aural Hematoma
How are Aural Hematomas treated?
Drain placement (14days), Surgery; E-collar; treat primary cause
What is the inflammationof the middle and/or inner ear structures?
Otitis Media and Interna
What is typically the cause of Otitis Media and Interna and what is the treatment?
bacterial infection; topical/oral anti-infectives, Meclizine, Cerenia, may require a TECA (surgery)
