Disorders of the Eyelids Flashcards
Congential Abnormalities
Ankyloblepharon
- Meaning
- Pathologic meaning & sequelae
- Ankyloblepharon: palpebral fissure sealed at birth (adhesion of the upper eyelid with the lower eyelid) -> if opened prematurely (before 10-15 days of age), can lead to KCS and ulcerations
- Pathologic Ankyloblephraon: delayed or complete failure of eyelid opening -> Sequela = Ophalmia Neonatorum
What causes Opthalmia Neonatorum in dogs v. cats?
Dogs: Staphylococcus
Cats: Chlamydia
Congential Abnormalities
Pathogenesis and sequelae of eyelid agenesis
- Complete or partially undeveloped eyelid – cats
- Sequelae: Friction b/w haired skin and cornea => keratitis
Congential Abnormalities
Pathogenesis & Signalment for Eyelid Dermoid
- Ectopic island of skin @ eyelid margin
- Genetic predispostion: french bulldogs, shih tzu, german shephers, dachsunds, dalmatians
Congential Abnormalities
Pathogenesis, signalment and sequelae (4) of Macroblepharon
- Overly large palpebral fissure
- Brachycephalic & spaniel breeds
- KCS, proptosis, lagophthalmos, pigmentary keratitis
How is a dog with Macroblepharon surgically corrected?
With lateral or medial canthoplasty
Congential Abnormalities
Pathogenesis, signalment and sequla of Lagophthalmos
- Inability to completely close the eyelids
Signalment:
-brachycephalic breeds = congential
- Acquired due to facial nerve paralysis, exopthalmia (globe displaced forward), bupthalmia (bigger-than-normal globe – glaucoma cases)
Sequela: Keratitis
Structural Abnormalities
Definitions of:
1. Distichiasis
2. Trichiasis
3. Ectopic cilia
Structural Abnormality
Pathogenesis and sequelae of Distichiasis
What are Meiboman glands?
Sebaceous glands along the rims of the eyelid inside the tarsal plate
Structural Abnormality
Pathogenesis and Sequelae of Trichiasis
Structural Abnormality
Pathogenesis & Sequelae of Ectopic Cilia
Structural Abnormality
What is an Entropion? Causes?
Inversion of the eyelid margin
- haired skin contacts the conjunctiva & corneal surfaces
Causes: blepharospasm, epiphora, corneal pigmentation & ulceration
Classifications of Entropion
- Primary = congenital or developmental
- Secondary = cicatricial or spastic
Primary: large and brachycephalic breeds, lateral and medial inversions, respectively
Spastic = so painful that the dog squints their eyes so hard (rolling eyelids in by chronic blepharospasm
What patients should have temporary tacking sutures for entropion treatment?
- animals < 6 months old
- high anesthetic risk patients
- spastic entropion cases
What patients should have permanent surgical correction?
Holtz-Celsus +/- wedge resection
- Fully grown dogs
What is an Ectropion?
the eversion of the eyelid margin -> over-exposure of the conjunctiva + corneal surfaces
Typically accompanied by macroblepharon
Classifications of Ectropion
- Conformational
- Transient Fatigue
- Secondary
Eyelid functions (3)
Identify
- Skin
- Muscles (orbicularis oculi m., levator palpebra superioris m.)
- Tarsal plate & meiboman glands
- Palpebral conjunctiva
Blepharitis
- definition
- sequelae
- possible etiologies
- treatmenet
Definition: inflammation of the eyelids
Sequelae: blepharospasm, hyperemia, edema, epiphora +/- ulceration
Possible Etiologies: infectious disease, allergic or immune-mediated reaction
Treatment: treat underlying condition, topical ABX / corticosteroids
What is a Chalazion? Treatment?
Impacted meibomian gland - firm, non-painful swelling
Treatment = warm compress, curettage +/- abx
equivalent to a stye
Most common canine eyelid neoplasms
Meibomian gland adenomas, Epitheliomas
Pink lobulated masses; benign!
?
Melanoma - can arise as single or multiple pigmented masses; less aggressive in dogs
Not systemically dangerous; are locally invasive, especially in horses
?
Papilloma - dog, benign
What is the most common eyelid neoplasm in cats and horses?
Squamous Cell Carcinoma - malignant
HIGH RECURRENCE RATE
also common in cats: MCTs, hemangiomas
Equine sarcoid?
Large, non-malignant skin tumors
- can occur anywhere on the body, but most commonly on the head // eye area
When is wedge resection / house incision made versus reconstructive blepharoplasty in the surgical resection of eyelid neoplasia?
Wedge: involing < 1/3 of eyelid
Reconstructive: involving >1/3 of eyelid
Spectacle vs Retained Spectacle
