Equine Conjunctival and Lacrimal Disorders

What are the 3 regions of conjunctiva?

The three regions of conjunctiva are the bulbar conjunctiva, palpebral conjunctiva, and fornix conjunctiva.

What is the third eyelid?

The third eyelid, also known as the nictitating membrane, is a translucent membrane in some animals that protects the eye, provides moisture, and helps remove debris.

What are the secretory components of the nasolacrimal apparatus?

Orbital lacrimal gland and the gland of the third eyelid.

What is epiphora?

Epiphora is the overflow of tears due to excessive production or insufficient drainage, often a sign of underlying eye disorders.

What are the 3 layers of tear film?

Lipid, aqueous, and mucin

What are the clinical signs of conjunctivitis?

Hyperemia, chemosis, discharge, blepharospasm

What are the most common types of bacterial conjunctivitis?

Staph and strep

What is the treatment for bacterial conjunctivitis?

broad spectrum topical antibiotics

What is the most common type of viral conjunctivitis?

Herpesvirus (EHV-2 or EHV-5)

What is the treatment for viral conjunctivitis?

Antivirals and anti-inflammatories

What is the most common type of conjunctivitis?

Allergic/immune-mediated

What is the treatment for allergic/immune-mediated conjunctivitis?

Topical anti-inflammatories and avoidance of allergens

What are the most common causes of parasitic conjunctivitis?

Habronema, onchocerca, thelazia

What is the treatment for parasitic conjunctivitis?

Systemic avermectins, topical anti-inflammatories, and surgical excision of granulomas.

What is keratoconjunctivitis sicca?

Quantitative tear deficiency

What are the clinical signs of KCS?

blepharospasm, conjunctivitis, mucoid discharge, ulcers, dry appearance, dull cornea with vascularization, pigmentation

What is a drug-induced cause of KCS?

Atropine

What is the treatment for KCS?

artificial tears, topical antibiotics, anticollagenases, lacrostimulants, tarsorrhaphy, parotid duct transposition

What is a qualitative/evaporative tear film deficiency?

Insufficient mucin or lipid production results in loss of tear film stability/premature evaporation

What is the treatment for a qualitative tear film deficiency?

treatment of underlying cause (inflammation, disrupted lid margins), temporary tarsorrhaphy, bandage contact lens, artificial tears

What is meibomianitis?

An uncommon inflammatory condition affecting the meibomian glands usually associated with chronic inflammatory conditions of the conj and eyelids

What is the treatment of meibomianitis?

curettage, topical and systemic antibiotics and anti-inflammatories

What is dacryocystitis?

Inflammation of the lacrimal sac and NL duct, often secondary to NLD obstruction

What are clinical signs of dacryocystitis?

mucopurulent discharge and secondary conjunctivitis

What is the treatment for dacryocystitis?

flushing/opening NLDm systemic and topic antibiotics, anti-inflammatories

What is a possible complication of third eyelid excision?

fat prolapse

What are potential causes of third eyelid protrusion?

ocular pain, decreased orbital tissue volume, decreased ocular size, retrobulbar disease, conjunctivitis, corneal disease, Horner’s, tetanus, HYPP, systemic illness, idiopathic

What is microphthalmia?

A condition where one or both eyes are abnormally small, possibly leading to vision impairment.

What is phthisis bulbi?

Phthisis bulbi is a degenerative condition of the eye characterized by shrinkage of the eyeball, often occurring after severe trauma, inflammation, or glaucoma. It leads to loss of vision and can result in a non-functional eye.