Final - Opthalmology Portion Flashcards
Cloudiness in the eye may be localized to what structures?
Cornea, Anterior chamber, Lens, Posterior segment (vitreous and retina)
What are the 4 conditions associated with a cloudy eye in the cornea?
Edema, Scar/Fibrosis, Lipid, Mineral
Corneal edema can be caused by what two conditions of the eye?
Ulceration and Endothelial Dysfunction
Endothelial dysfunction can lead to what other conditions of the eye?
Anterior uveitis, glaucoma, endothelial degeneration, localized dysfunction
What conditions of the eye cause corneal scarring or fibrosis?
Prior ulcer/trauma, chronic exposure, chronic abrasion
Chronic exposure of the eye is caused from what two conditions?
Lagophthalmos and KCS
Chronic abrasion of the eye can be caused by what three conditions?
Entropion, Distichia, Ectopic cilia
What causes lipid degeneration?
Prior keratitis, infiltrative corneal disease, topical corticosteroids, systemic metabolic disease
What two causes leads to a corneal lipid (lipid keratopathy)?
Lipid dystrophy and lipid degeneration
What are the two causes of corneal mineralization?
Degeneration (age related or ocular disease) and Metabolic (systemic metabolic disease)
Ocular pain related to a cloudy cornea is caused by what?
Edema
What is the difference between aqueous flare and lipid flare?
- Aqueous flare is caused by uveitis
- Lipid flare is caused by metabolic/hyperlipidemia +/- uveitis
Lipid flare and aqueous flare is localized to what part of the eye?
Anterior chamber
What will you see when focal light source is directed through the anterior chamber if you suspect aqueous flare?
Tyndall effect
What dealing with the lens what two conditions are you worried about?
Cataracts and Nuclear sclerosis
When you are worried about the posterior segment of the eye, what two structures are you referring to?
Vitreous and Retina
What issues are associated with the vitreous vs. the retina?
- Vitreous = vitreous haze due to inflammation, asteroid hyalosis, synchesis scintillans
- Retina = retinal detachment
Study photo
Look up something you don’t understand
What are the 3 basic events that happen during intraocular inflammation?
Increased blood supply, augmented vessel permeability, white blood cell migration
Inflammation is generated by what 3 things?
Release of chemical mediators, presence of certain pathogen-associated molecules, and release of pro-inflammatory molecules by immune cells
What are some ocular clinical signs you will see with uveitis?
Aqueous flare, ciliary flush, corneal edema, episcleral injection, hyphema, hypopyon, keratin precipitates, miosis, rubiosis irides, synechiae
This is defined as 360 degree vascularization
Ciliary flush
This is defined as fluid buildup within the stroma caused by altered function of the corneal endothelium
Corneal edema
This is pupillary constriction and painful spasm of the ciliary body muscular
Miosis
This is defined as the adherence of the iris to the cornea (anterior) or lens (posterior) lead by inflammatory cells, fibrin, and fibroblasts
Synechiae
This is defined as protein in aqueous humor (anterior chamber) - disruption of BAB and viewed as a hazy anterior chamber
Aqueous flare
This is defined as WBCs in aqueous humor (anterior chamber) particularly neutrophils
Hypopyon
This is defined as RBCs in the aqueous humor (anterior chamber)
Hyphema
This is defined as inflammatory cells, fibrin, and iris pigment adhered to endothelium (innermost layer of cornea)
Keratic precipitates
This is the injection of the iridal blood vessels
Rubiosis irides
This is defined as low intraocular pressure
Hypotony
What ocular structure is responsible for aqueous humor production?
Ciliary body
What are some potential complications of intraocular inflammatory diseases?
Synechiae, Iris bombe, corneal edema and degeneration, cataracts, lens instability, vitreous degeneration, retinal detachment, secondary glaucoma, phthisis bulbi
What are the common clues that lead to uveitis?
Miosis, low IOP, aqueous flare, hypopyon, hyphema
What are 3 primary causes of ocular disease?
Cataracts, lens rupture, corneal ulcer
Idiopathic uveitis is more common what species?
Cats
What are general causes of uveitis?
Primary ocular disease, idiopathic, trauma, ocular manifestations of systemic diseases
What are common causes of uveitis in dogs?
Infectious, Len-induced (phaolytic or phacoclastic), reflex uveitis
This is defined as soluble lens protein that leaks through an intact lens capsule (cataract)
Phacolytic uveitis
This is defined as the sudden exposure of intact lens protein (lens capsule tear - trauma)
Phacoclastic uveitis
Reflex uveitis is associated with what structures of the eye?
Cornea and sclera
What is the common primary neoplasia that causes uveitis in dogs?
Melanoma
What is the most common metastatic neoplasia that causes uveitis in dogs?
Lymphoma
Pigmentary uveitis is also known as what?
Golden retriever uveitis
What are breed specific causes of uveitis?
Uveodermatologic syndrome and Pigmentary uveitis (golden retriever uveitis)
What is a metabolic cause of uveitis?
Hyperlipidemia
What are common infectious causes of uveitis in cats?
Viral (FeLV, FIP, FHV-1), Bacterial (Bartonella), Fungal (Histoplasma, Blastomyces, Coccidioides), and Protozoal (Toxoplasma)
What is metabolic cause of uveitis in cats?
Systemic hypertension
What is the most common neoplastic cause of uveitis in cats?
Lymphoma
In cases of uveitis, when should you do ultrasound?
ONLY if you cannot see past the iris and lens
What are the treatment goals for uveitis?
Control pain, prevent sequelae, stabilize and restore blood-aqueous barrier, and treat the underlying cause when possible!
Name some topical treatments for uveitis
- Topical anti-inflammatories: corticosteroids (prednisolone acetate, dexamethasone), non-steroidal anti-inflammatories (diclofenac, ketorolac)
- Topical atropine (mydriatic and cycloplegic)
When are corticosteroids contraindicated in uveitis cases?
Potentiate infections, decrease wound healing, ulcerative keratolysis, corneal lipid/calcium deposition
When is atropine contraindicated in cases of uveitis?
Lens instability, glaucoma, dry eye
In cases of uveitis treatment, what do you need to have checked before administering system steroids?
Diagnostics, because CS can be exacerbated by suppressing the immune system
This is a Multifactorial disease that is characterized by elevation of intraocular pressure incompatible with ocular health. It cause irreversible vision loss through optic nerve and ganglion cell death
Glaucoma
This type of glaucoma is defined as heritable/breed-related abnormality of aqueous drainage angle
Primary glaucoma
This type of glaucoma is defined as numerous causes of secondary drainage angle obstruction
Secondary glaucoma
What are some causes of canine secondary glaucoma?
Lens luxation, uveitis, hyphema, intraocular neoplasia, melanocytic glaucoma (cairn terrier), Pigmentary uveitis (golden retrievers), pseudophakia/aphakia, trauma
(T/F) Primary glaucoma is common in cats
False! It is rare
What is the most common cause of secondary glaucoma in cats?
Uveitis, due to the misdirection of aqueous humor (unique to cats)
What are 3 mechanisms of vision loss in glaucoma?
High intraocular pressure, optic nerve ischemia, neurotoxic events
What are acute clinical signs of glaucoma?
Blepharospasm, corneal edema, episcleral injection, dilated pupils, variable vision
What are chronic signs of glaucoma?
All acute signs, buphthalmos, haab’s striae, lens subluxation, cupped optic nerve
How do you diagnose glaucoma?
Clinical signs, history/signalment, IOP, gonioscopy
What is the considered the primary means of diagnosing and assessing glaucoma therapy?
Tonometry
Gonioscopy helps determine the likelihood of what based upon angle morphology?
Primary glaucoma
What are the goals of glaucoma therapy?
Maintenance of vision, patient comfort, prophylaxis in “at risk” eyes
Name the classes of drug used to treat glaucoma
- systemic hyperosmotic medications
- carbonic anhydrase inhibitors
- miotics
- prostaglandin analogues
- b-adrenergic blocking agents
What drug do you want to use for emergency management of glaucoma topically and systemically?
- Topically = Latanoprost
- Systemically = IV mannitol or oral glycerin (hyperosmotics)
What drug class do you want to use for maintenance medications that is the most useful single drug class in all types of glaucoma?
Carbonic Anhydrase Inhibitors
What are some examples of carbonic anhydrase inhibitors?
Dorzolamide and Brinzolamide
What is another maintenance medication for glaucoma besides CAIs?
Miotics (topical)
When should you avoid using a miotic as a maintenance medication for glaucoma?
When the glaucoma is secondary to uveitis or anterior lens luxation
What are some examples of topical miotics?
Demarcarium bromide and Pilocarpine
Name 3 prostaglandin analogues and what is important about them?
Latanoprost, Travoprost, and Bimatoprost
- They are NOT effective in cats
A topical B-blocker used as a glaucoma medication is for what stage of treating glaucoma?
Maintenance medication that is also useful in prophylaxis of at-risk eyes
Name 2 topical B-blockers
Timolol maleate and Betxolol
A high normal IOP is considered what in glaucoma patients?
Undesirable; < 15-20 mmHg is ideal
With medical prophylaxis of glaucoma in the second eye, what classes of drugs are you using?
Topical miotics, CAIs, and B-blockers
What drug class is contraindications when treating glaucoma?
Topical MYDRIATIC (atropine, tropicamide)
What does surgical management of glaucoma do?
Decrease aqueous production or increase aqueous outflow
The long-term visual prognosis of glaucoma patient is what?
Poor
What are the salvage procedures that can be performed?
Enucleation, Evisceration/Intrascleral prosthesis, Chemical ciliary body ablation
Chemical ciliary body ablation can only be done in what type of eyes for glaucoma patients? What drug is being injected?
BLIND eyes; Gentamicin
What are some causes of corneal ulcers?
Trauma, Corneal abrasion due to adnexal disease, tear film deficiency, exposure keratitis, infection
What 3 types of ulcer are still able to heal?
Acute superficial ulcer, mid-stromal ulcer, deep stromal ulcer
Corneal ulcers generally heal within how many days?
7-10 days
What is always indicated when diagnosing corneal ulcers?
Searching for underlying cause and STT
What tests are specifically indicated when diagnosing corneal ulcers?
Corneal culture and cytology
What are the specific causes of delayed corneal healing?
Corneal infection, unresolved source of corneal abrasion (Distichia, ectopic cilia, Entropion, foreign body), KCS, exposure keratitis, neutrophic keratitis, SCCED
What is the cause of a primary infectious ulcer in a cat?
Herpesvirus
What does a secondary corneal infection result in?
Progressive destruction of corneal stroma
This is defined as the inward rolling of eyelids causing hairs to abrade cornea
Entropion (conformational or spastic Entropion)
This is the single or multiple abnormal hairs protruding from meibomian gland openings of eyelids that may or may not cause clinical problems
Distichia
This is abnormal hairs protruding through conjunctival surface of the eyelid that is ALWAYS symptomatic
Ectopic cilia (most common in young dogs and toy breeds)
This is a common cause of corneal ulcers and delayed healing in dogs and is readily diagnosed by STT
KCS
Conformational exophthalmos, inability to blink due to facial paralysis, exophthalmos due to orbital disease, buphthalmos due to glaucoma are all causes of what?
Exposure keratitis
This is the loss of corneal sensation that results in spontaneous non-healing ulceration
Neutrophic keratitis (ophthalmic branch of the trigeminal nerve)
This is characterized by a chronic, non-healing superficial corneal ulcer for which NO underlying cause can be determined (middle aged dogs most commonly affected)
Spontaneous Chronic Corneal Epithelial Defect (SCCED)
What type of ulcer can be approached medically and surgically?
Deep stromal ulcer
What are the goals of medical therapy for a corneal ulcer?
- Prevent/control infection
- Prevent/control collagenolysis
- Increase patient comfort
- Promote corneal healing
Describe plan for an acute superficial ulcer
- Diagnostics: rule out underlying conditions
- Tx: topical broad spectrum abx, topical atropine, analgesic PRN
- Follow-up: recheck q 2-3 days, stain to monitor ulcer size
A chronic ulcer is defined as an ulcer that has not healed within how many days?
7-10 days
What are the 3 characteristics that lead to a SCCED diagnosis?
Chronic clinical course, lack of identifiable cause, clinical appearance
What are some clinical characteristics of SCCED?
Chronic superficial corneal ulcer, epithelial lip (flourescein staining pattern), variable corneal pain and vascularization
(T/F) animals with SCCED rarely develop infections
TRUE
The following is pathogenesis understood for what condition:
- hyalinized acellular anterior corneal stroma prevents corneal epithelial adhesion
- epithelial non-adherence usually extends well beyond obvious region of ulcer
SCCED
How is SCCED treated?
Epithelial debridement, surgical procedures such as anterior stromal puncture (grid keratotomy and burr keratotomy) and superficial keratectomy
What part of treating SCCED is mandatory?
Epithelial debridement
During an anterior stromal puncture for treating SCCED, exposure to what facilitates epithelial adhesion complex formation?
Type I collagen
For a SCCED follow-up, if it is not healed with what time frame what should you do next?
2-3 weeks; sx tx should be repeated if not healed
Describe the diagnostic plan for mid-stromal ulceration
- Diagnostics: investigate underlying factors, corneal C&S and cytology
- Tx: topical broad spectrum abx, protease inhibitors, topical atropine, analgesics PRN
- Follow-up: q 24 hours, then 48 hours
Describe a plan for deep stromal ulcers/melting ulcers
- Diagnostics: investigate risk factors, corneal C&S and cytology
- Tx: topical broad spectrum abx, protease inhibitors, topical atropine, analgesic PRN
- Follow-up: hospitalize or recheck q 24h
Describe a plan for descemtocele s
- Diagnostics: corneal cytology to culture (obtained from ulcer EDGES), STT
- Tx: SURGERY (conjunctival flap, CCT), topical abx
- Follow-up: recheck at 1 and 3 weeks, discontinue abx at 3 weeks, trim flap at 4-6 weeks
What are the pre-operative treatments for a corneal perforation?
- Topical broad spectrum abx
- Topical atropine
- Systemic broad spectrum abx
- Systemic anti-inflammatory
This clinical sign of the eye is a common presentation of systemic disease
Redness
This is defined as diffuse redness or small network of vessels of either the bulbar or palpebral conjunctiva
Conjunctival hyperemia
This is the distinct, relatively straight vessels that are adherent to the sclera
Episcleral injection
This is the loss of physiologic corneal transparency where the vessel type/location is defined by its appearance
Corneal neovascularization (deep/Stromal vessels, superficial vessels, and 360 degree deep neovascularization)
What are the two types of hemorrhage (blood outside of vessels) in the eye?
Subconjunctival hemorrhage and Hyphema
You will often see long, branching corneal vessels and conjunctival hyperemia with what condition?
Superficial keratitis/KCS
With an intraocular disease, what kind of redness will you see?
Episcleral injection, conjunctival hyperemia, 360 degree deep corneal vessels
What are the most important immediate rule out for red eye before treating empirically?
Corneal ulcer, dry eye, glaucoma, uveitis
Classify mild and dramatic anisocoria
Mild = afferent and Dramatic = efferent
What are non-neurological causes of mydriasis and miosis?
Mydriasis = iris atrophy, glaucoma, pharmacologic
Miosis = uveitis, keratitis, posterior synechia, pharmacologic
This is a hereditary, degenerative disorder of the rods and cons. Secondary cataract formation is common
Progressive retinal atrophy
This usually presents as a complete loss of vision in dogs that is commonly bilateral
Canine Optic Neuritis