Eye Diseases Flashcards
Conjunctivitis caused by
Rarely a 1° disease process, find underlying cause
Immune-mediated, allergic, anatomic, bacterial
Conjunctivitis clinical signs
Chemosis (conjunctival swelling)
Hyperemia (redness)
Ocular discharge (serous or purulent)
Conjunctivitis dx
PE: diagnose 1° disease
r/o foreign bodies or the presence of follicles +/- Schirmer tear test
Conjunctival scraping 🡪 cytology, C&S
Conjunctivitis tx
Resolve underlying systemic disease
Topical antibiotics
Nonsteroidal ointments
Keep eyes clear of dried exudate
Topical antivirals
Epiphora
Overproduction of tears
Epiphora caused by
Faulty drainage by the lacrimal system
Brachycephalics
Entropion or ectropion
Epiphora —-Faulty drainage by the lacrimal system
Blockage of the lacrimal duct by swelling or inflammatory cells
Imperforate puncta
Trauma
Epiphora —Brachycephalics
Large globes in shallow orbit
Little room for tear accumulation
Epiphora clinical signs
“Watering” eyes – acute or chronic
Wet facial hair in the medial canthus
2° bacterial infection of the skin at the medial canthus
“Tear staining”
Epiphora dx
Complete eye exam
Test patency of nasolacrimal system using fluorescein stain
Epiphora tx
Treat the primary cause of eye pain/irritation
Flush the nasolacrimal ducts
Surgically open imperforate puncta
Keep facial hair trimmed
Entropion
Eyelid rolls in against the cornea
Ectropion
Eyelid rolls outward, exposing the cornea
Entropion signs
rolling in of the lid margin(s), epiphora, chemosis, conjunctival erythema, conjunctivitis, blepharospasm, pain, +/- corneal ulcer, photophobia
Ectropion signs
lid eversion, conjunctivitis, epiphora, keratitis, purulent exudate
Entropion and Ectropion dx
Observe the lids and their interaction with
the globe
Complete ocular exam: cornea, conjunctiva, lid margins
Do not sedate patient
Entropion and Ectropion tx
Sx correction
Glaucoma
Severely elevated intraocular pressure (IOP
Glaucoma leads to
Eyeball = a relatively closed system housed
in a bony orbit
An ↑ in globe contents 🡪 ↑ IOP b/c expansion is
limited
More aqueous fluid is produced than leaves the eye
Glaucoma classification primary
inherited, affects both eyes
Glaucoma secondary class
obstruction of the drainage angles 2° to another disease process of the eye
Glaucoma acute
IOP>60 mm HG —>disruption of retinal ganglion cells and circulation —>blindness
Goal of tx: ↓IOP rapidly to prevent permanent injury
Glaucoma chronic
sustained ↑ IOP 🡪 painful, blind eye,
unresponsive to medical therapy
Glaucoma normal IOP
Canine/feline = 12 – 22 mm Hg
Glaucoma acute clinical signs
Ocular pain
Conjunctival and episcleral injection
Diffuse corneal edema
Dilated pupil, ↓ or absent PLR
+/- blindness
Glaucoma chronic signs
Buphthalmias (enlarged globe)
Corneal striae, optic disk cupping
Pain
Blindness
Glaucomadx
Measured IOP 30 mm Hg or greater
Tonometer
Clinical signs
r/o lens luxation as cause
Glaucoma acute drug therapy
Drug therapy: ↓ aqueous humor production, facilitate and ↑ aqueous outflow, diuretics
Glaucoma chronic tx
Surgical: procedures that ↓aqueous production by destroying part of the ciliary body, procedures that ↑ aqueous outflow
Ulcerative Keratitis (Corneal Ulcers)
A full-thickness loss of corneal epithelium 🡪 exposed stroma
Ulcerative Keratitis (Corneal Ulcers)
A full-thickness loss of corneal epithelium 🡪 exposed stroma
Ulcerative Keratitis (Corneal Ulcers) corneal layers
Epithelium
Stroma
Descemet membrane
Endothelium
Ulcerative Keratitis (Corneal Ulcers) watch healing …
Pain control and an e-collar
Uncomplicated ulcers will heal in 24-48 hours
If ulcer breaches stroma and enters Descemet’s membrane 🡪 rupture
Ulcerative Keratitis (Corneal Ulcers) clinical signs
Epiphora
Blepharospasm (pain)
Conjunctival hyperemia
Ulcerative Keratitis (Corneal Ulcers) dx
Thorough eye exam
Fluorescein stain
Absorbed well by stroma but not epithelium
Possible C&S
Keratoconjunctivitis Sicca (KCS) tx
Drug therapy: atropine for pain and blepharospasm, topical antibiotics, blood serum from patient
DO NOT use steroids in an ulcerated eye!!!
Surgery
Keratoconjunctivitis Sicca (KCS) AKA
Chronic dry eye
Keratoconjunctivitis Sicca (KCS)
Loss of function (atrophy) of both lacrimal
glands
Keratoconjunctivitis Sicca (KCS) types
Orbital
Nictitans
Keratoconjunctivitis Sicca (KCS) orbital
Lateral superior orbit
70% of tear production
Keratoconjunctivitis Sicca (KCS) nictitans
Base of 3rd eyelid
30% of tear production
Keratoconjunctivitis Sicca (KCS) clinical signs
Recurrent conjunctivitis and corneal ulcers
Cornea and conjunctiva appear dull, dry, and irregular
Severe mucoid ocular discharge on lid margins and medial canthus
Blepharospasm
Keratoconjunctivitis Sicca (KCS) dx
Schirmer tear test <15 mm/min
Normal: dogs – 15-25 mm/min, cats –
11-23 mm/min
Tx for Keratoconjunctivitis Sicca (KCS)
Drug therapy: tear stimulation, topical artificial tear ointments
Cataracts
An opacity of the lens sufficient to cause a reduction in visual function
Cataracts causes
cause of blindness in dogs, less common in cats
Inherited or secondary to other diseases/trauma
Cataracts not
lenticular sclerosis
Normal change in ageing animals, causes lens opacity but vision is maintained
Cataracts clinical signs
Progressive loss of vision
Opaque pupillary opening
Signs related to systemic disease (diabetes mellitus, hypocalcemia)
Cataracts dx
Complete ophthalmic exam
Vision assessment
Normal PLR
Cataracts tx
Surgical removal of the cataract
Treatment of systemic disease
Blepharospasm (pain)
Blinking excessively
