Corneal Ulceration and Perforation Flashcards by Shelly Underwood

What are some causes of corneal ulcers?

-Trauma
-Corneal abrasion due to adnexal disease
-Tear film deficiency
-Exposure Keratitis
-Infection

How well did you know this?

Not at all

Perfectly

What is the order of ulcer to corneal perforation?

Acute superficial ulcer
Mid-stromal ulcer
Deep stromal ulcer
Descemetocele
Corneal Perforation

Acute can become chronic

Acute, mid-stromal and deep can heal (Need stroma left in the eye)

How well did you know this?

Not at all

Perfectly

Under normal circumstances how long does it take corneal ulcers to heal?

7-10 days (can be faster)

How well did you know this?

Not at all

Perfectly

What diagnostics should you run if you think you may have a corneal ulcer?

Always - search for underlying cause and a Schirmer teat test

Specific indications: Corneal culture and corneal cytology

Usually: Fluorescein stain

How well did you know this?

Not at all

Perfectly

What are some risk factors for corneal ulcers?

-Is tear production normal?
-Can and does the animal blink normal?
-Brachycephalic breed (exophthalmos) and pathologic exophthalmos
-Adnexal abnormalities
-Infection?

How well did you know this?

Not at all

Perfectly

What are some signs of corneal ulcer?

-Injected Sclera
-Yellow/hypopyon in cornea
-Corneal Edema

How well did you know this?

Not at all

Perfectly

What are some causes of delayed corneal healing?

-Corneal infection
-Unresolved source of corneal abrasion
-Keratoconjunctivitis Sicca
-Exposure Keratitis
-Neurotrophic Keratitis
-SCCED (Boxer ulcer, indolent ulcer)

How well did you know this?

Not at all

Perfectly

What are the 2 causes of corneal infection?

Primary - Herpesvirus
Secondary - bacterial and fungal, progressive destruction cornea, stroma, increased size and depth

How well did you know this?

Not at all

Perfectly

What is entropion?

Inward rolling of the eyelids causing hairs to abrade the cornea
-Conformational and spastic

How well did you know this?

Not at all

Perfectly

What is distichia?

Single or multiple abnormal hairs protrude from meibomian gland opening of eyelid
- Symptoms vary and age considerations

How well did you know this?

Not at all

Perfectly

What is an ectopic cilia?

Abnormal hairs protruding through the conjunctival surface of eyelid
-Symptomatic
-Common in young dogs
-Toy breed commonly effected

How well did you know this?

Not at all

Perfectly

What is keratoconjunctivitis Sicca?

-Common cause corneal ulcer and delayed healing in dogs
-Mucopurulent ocular discharge, conjunctival hyperemia, vascularizing keratitis
-ID with Schirmer Tear Test

How well did you know this?

Not at all

Perfectly

What is exposure Keratitis?

-Conformational exophthalmos
-Inability to blink due to facial paralysis
-Exophthalmos due to orbital disease
-Buphthalmos due to glaucoma
-Touch eyelid and see if they can blink over the whole thing

How well did you know this?

Not at all

Perfectly

What is Neurotrophic Ketatitis?

-Loss of corneal sensation = spontaneous non-healing ulceration
-Opthalmic branch trigeminal nerve
-Uncommon

How well did you know this?

Not at all

Perfectly

What is SCCED?

-Spontaneous Chronic Corneal Epithelial Defect
-Chronic non-healing superficial corneal ulcer - no underlying cause determined
-Middle-aged dogs
-Boxer ulcer, indolent ulcer, refractory ulcer, recurrent erosion

How well did you know this?

Not at all

Perfectly

Do you treat medially or surgically for each of the listed?
Acute Superficial
Mid-Stromal
Deep Stromal
Descemetocele
Corneal Perforation
Chronic Superficial

Acute Superficial - Medical
Mid-Stromal- Medical
Deep Stromal - Medical/Surgical
Descemetocele -Surgical
Corneal Perforation -Surgical
Chronic Superficial - Surgical

What are the goals of medical therapy for corneal ulcerations?

-Prevent/control infection
-Prevent/control collagenolysis
-Increased patient comfort
-Promote corneal healing
Use antibiotics on all ulcers - don’t stop until epithelized = no stain

What bacteria commonly causes melting ulcers?

Pseudomonas

What are a majority of the ulcers encountered in practice?

Superficial (Acute)

What are the diagnostics, treatment and follow up for acute superficial ulcers?

Diagnostics: rule out underlying conditions

Treatment:
-Borad spectrum antibiotics BID/TID
-Topical atropine SID/BID
-Analgesic PRN (NSAID)

Follow up
-Recheck every 2-3 days
-Fluorescein stain to monitor

What are the diagnostics, treatment and follow up for chronic superficial ulcers?

Chronic - haven’t healed in 7-10 days

Diagnostics - underlying reason for non-healing

Treatment - medical or surgical - ID underlying issue

What are the diagnostics, treatment and follow up for SCCED?

Chronic clinical course, lack ID cause, clinical appearance

What are clinical characteristics of SCCED?

-Chronic superficial corneal ulcer
-Epithelial Lip (fluorescein stain)
-Variable corneal pain and vascularization
-Change in size, wont heal completely with medical alone
-Rarely become infected

What is the pathogenesis of SCCED?

-Not fully understood
-Hyalinized acellular anterior corneal stroma prevent corneal epithelial adhesion
-Epithelial non-adherence usually extend well beyond obvious region of ulcer

What is the treatment for SCCED?

-Epithelial debridement (Numb and push on it with a cotton swab) -Surgical - anterior stromal puncture (Grid keratotomy, Burr Keratotomy) -Superficial keratectomy -3rd eyelid flap or contact lens -topical antibiotics until healed (solution vs ointment) -E-collar may be required ***Debridement mandatory - topical anesthetic alone, dry cotton swab, debride vigorously*** -Ulcer may appear enlarged -Debridement alone will not ensure healing -Anterior Stromal Puncture - grid or burr keratotomy (penetrate hyalinized anterior corneal stroma, 1 collagen)

How do you perform a grid keratotomy?

-Use a 25 gauge needle -Lightly scratch across ulcer bed -Begin and end in normal epithelium -Place scratches 1 mm apart

How do you perform a Burr Keratotomy?

Dremel like tool, post op infection higher

How do you manage a keratotomy postop?

-Apply topical antibiotic 3-4 times daily until healed -90% heal in 10-14 days -3rd eyelid flap or contact Lense -E-collar -Repeat procedure may be needed

What are your follow up recommendations for SCCED?

-Recheck 1x week -Not healed 2-3 weeks surgical treatment repeated -Don't debride for at least 2-3 weeks following surgery (6 week for complete development of epithelial adhesion complexes)

What causes SCCED in cats?

Feline Herpesvirus -Debridement may help or cause corneal sequestrum formation

What are the diagnostics and treatment for Mid-stromal Ulceration?

Diagnostics: Investigate underlying factors, corneal culture and sensitivity, corneal cytology Treatment: -Topical antibiotic, broad spectrum every 4-6 hours, solutions preferred -Protease inhibitors (tetracycline and autogenous serum e 4-6 hours, topical atropine, analgesia) Follow up: recheck every 24 hours then 48hrs

What are the diagnostics, treatment and follow up for deep stromal ulcers or melting ulcers?

Diagnostics: investigate risk factors, corneal culture and sensitivity, corneal cytology Treatment: -topical antibiotics, broad spectrum antibiotics 2-4 hours -Protease inhibitor - tetracycline, autogenous serum 2-4 hr Follow-up: Hospitalize and recheck ever 24 hours

What are the diagnostics, treatment and follow up for a Descemetocele?

Surgical Case -Medical management- deep ulcer -Diagnostics: corneal cytology or culture, ulcer edged, Schirmer tear test -Surgical treatment: Conjuctival flap, corneoconjuctival transposition topical antibiotics, proteolytic inhibitors and e-collar Follow up - recheck 1-3 weeks post op, discontinue antibiotic 3 week post op, trim flap pedicel 4-6 week post op

What are the diagnostics, treatment and follow up for corneal perforation?

Surgical condition Diagnosis - history, culture and radiograph Post-operative -Topical broad spectrum antibiotic 4-6 hr -Topical atropine 6-8hr -Systemic broad spectrum antibiotics -Systemic anti-inflammatory -E-collar