Conjunctiva Flashcards
What cells predominate on a conjunctival cytology in a patient with conjunctivitis?
Epithelial cells and neutrophils
What is epiphora?
Excessive tearing
What part of the conjunctiva is responsible for producing the normal mucinous layer of the tear film?
Goblet cells
(increased production results in mucoid ocular discharge)
What is the function of goblet cells within the conjunctiva of the eye?
- Produces the mucinous layer of the tear film normally
- Inflammation triggers increased production and mucoid discharge
Why is mucopurulent discharge often seen with quantitative KCS?
Inflammation of the cornea and conjunctiva leads to increased mucin production by goblet cells, which then creates a favorable media for bacterial growth
Where are lymphoid follicles of the eye normally located?
Bulbar surface of the 3rd eyelid
always abnormal if present anywhere else
Lymphoid follicles found in places other than the bulbar surface of the 3rd eyelid indicates?
- Nonspecific antigenic stimulation
- Likely primary conjunctivitis
What does conjunctival hyperemia suggest?
Superficial irritation
Ex: conjunctivitis, superficial corneal ulcer, KCS
What is episcleral injection and what is it suggestive of?
Congestion of deeper larger eye vessels
Suggestive of deeper inflammation
Ex: Deep corneal ulcer, uveitis, glaucoma, episcleritis
What is the most common cause of conjunctivitis in dogs?
KCS / dry eye
List canine disorders of the conjunctiva
- KCS
- Allergic conjunctivitis
- Infectious conjunctivitis (Adenovirus, Herpesvirus, Distemper)
What are infectious causes of conjunctivitis in dogs?
- Adenovirus
- Herpesvirus
- Distemper
(primary conjunctivitis… which is less common)
What are clinical signs that can be seen with primary conjunctivitis?
- Blepharospasm
- Epiphora
- Mucoid discharge
- Hyperemia
- Lymphoid follicles
(Viral conjunctivitis and allergic conjunctivitis are primary causes although rare)
What are the possible treatment options for canine patients with conjunctivitis?
- Treat underlying cause (allergy vs viral)
- NeoPolyDex
- Diclofenac
- Optimmune (Cyclosporine)
(topical anti-inflammatories are mainstay tx options)
List the most common causes of feline conjunctivitis in order of prevalence
- Herpesvirus
- Chlamydia
- Mycoplasma
- Calicivirus
**Only herpesvirus causes inflammation of both the conjunctiva AND cornea)
What is the most common cause of keratoconjunctivitis in cats?
Feline herpesvirus
What clinical signs in cats are suggestive of feline herpesvirus?
- Blepharospasm
- Epiphora
- Mucoid discharge
- URT infection !!
- Hyperemia
- Conjunctival AND corneal ulceration
- Dendritic (branching) corneal ulceration (pathognomonic)
- Symblepharon
What cranial nerve can be affected in cats with herpesvirus?
CN V, invades sensory nerve endings, remains latent in trigeminal nerve
What is the redrudescence phase of feline herpesvirus?
- Latent virus becomes reactivated by stress, steroids, co-infection, etc
What is a pathognomonic findings in cats with herpesvirus?
- Dendritic (branching) corneal ulcers
- Keratic precipitates ventrally
What is symblepharon?
Permanent adhesion between the conjunctiva and cornea
(happens with herpesvirus in cats)
What is the treatment protocol for cats with herpesvirus infection?
- Topical Cidofovir
- Famciclovir PO
- Topical erythromycin Abx for supportive care
What is feline eosinophilic keratoconjunctivitis?
Autoimmune disorder of the conjunctiva that may be related to feline herpesvirus
What is the most specific finding in cats with feline eosinophilic keratoconjunctivitis?
Raised white or yellow corneal and/or conjunctival infiltrates on the eye
What is the treatment protocol for cats with feline eosinophilic keratoconjunctivitis?
- Cyclosporine (to suppress immune system)
- Topical NSAID (or steroid if 100% certain of no ulcer)
- Cidofovir or Famcyclovir (antivirals)
What clinical signs can be suggestive of chlamydia in cats?
- Chemosis (most specific CS, all others non specific)
- Blepharospasm
- Epiphora
- Mucoid/purulent discharge
- Hyperemia
will not see corneal or conjunctival ulceration
What is the treatment protocol for cats with chlamydia?
- Topical tetracyclines or erythromycin
- Doxycycline PO (not great… esophageal strictures in cats)
Treat for 3 weeks minimum!!
What is the treatment protocol for cats with mycoplasma?
- Topical tetracyclines or erythromycin
- Doxycycline PO (not great… esophageal strictures in cats)
Treat for 3 weeks minimum!!
(same tx as chlamydia)
What is a pathognomonic clinical sign seen in cats with calicivirus?
Oral ulcers
What is the treatment protocol for cats with calicivirus conjunctivitis?
Topical erythromycin
