Eyelids Flashcards
List the glands of the eyelids
- Meibomian/tarsal glands
- Glands of Zeis
- Glands of Moll
Summarise the glands of the eyelids
- Their secretions form a part of the PTF (precorneal tear film)
- This coats the lid margins, preventing the tear overflow
List the muscles of the eyelid
- m. orbicularis oculi
- m. levator palpebrae
- m. malaris
These all connect with the tarsus (CT of the eyelid)
Give the functions of the eyelid
- Physical protection of the globe
- Distribution of the PTF; pumping it into the drainage system
- Production of phospholipid-rich secretion
List the notable lesions seen in the eyelid
- Prominent nasal fold
- Disorders of the ciliae
- Entropion
- Ectropion
- Hordeolum
- Blepharitis
- Trauma
- Neoplasia
Notable lesion seen in the eyelid: Prominent nasal fold
- CSx
- Tx
- Brachycephalic breeds; permanent irritation to the cornea
- CSx: Lacrimation; medial pigmentation & corneal vascularisation
- Tx: Sx removal of the fold; tx of 2° corneal ulcers
Notable lesion seen in the eyelid: List the disorders of the ciliae
- Districhiasis
- Trichiasis
- Ectopia ciliae
Disorder of the ciliae: Distichiasis
Additional ciliae originating from abnormally located follicles
Follicles are in/near the tarsal gland
Disorder of the ciliae: Trichiasis
Ciliae arising from the normally located follicles point in abnormal directions
Disorder of the ciliae: Ectopia ciliae
Additional cilia originating from the abnormally located follicle
The follicle may be located anywhere e.g under the palpebral conjunctiva
Disorders of the ciliae: Signs to look for
- Abnormal ciliae rub the corneal surface & conjunctiva
- Conjunctival hyperaemia
- Lacrimation
- Blepharospasm
- Miosis
Disorders of the ciliae: Treatment
- Trimming of the aberrant ciliae (by owner)
- Electroepilation & microepilation
- Surgical excision
- Treatment of any 2° corneal erosions
Notable lesion seen in the eyelid: Entropion
Inward turning of the eyelid margin
- Developmental or structural
- Acquired or congenital
- Spastic
Usually caused by the lower lid
Developmental/structural entropion: Incidence
- Lambs (upper lid)
- Dogs (lower lid)
- Usually affecting both eyes & whole lid margin
Developmental/structural entropion: Predisposed dog breeds
- Rottweiler
- Chow chow
- St. Bernard
- Great Dane
Acquired/cicatrical (scar) entropion: Aetiology
- Trauma to the lids → scar formation & skin contraction
- May be caused by periocular surgery or chronic inflammation
- Frequent in horses
This is the same aetiology as ectropion
Spastic entropion: Aetiology
Ocular pain/discomfort → Blepharospasm → 2° Entropion
- Common in dog
- Topical anaesthesia: Helps to make a dx whether the condition is structural or spastic
Entropion: Signs to look for
- Lacrimation, blepharospasm or photophobia
- Conjunctivitis
- Rubbing of the eye
- Corneal oedema, vascularisation, pigmentation
- Ulceration
- Turning of the lid margin
Entropion: Treatment
Surgery
Developmental entropion: May improve spontaneously in immature dogs
Entropion treament: Surgical techniques
Prior to anaesthesia, the lid is inverted to estimate how much skin is to be removed
- Hotz-Celsus technique
- “Pinch” technique
Entropion surgery: Postoperative tx
- ABx; NSAIDS; Elizabethan collar
- Sutures removal after 10-12 days
- Spastic entropion: Tx of the underlying condition
Notable lesion seen in the eyelid: Ectropion
Eversion & turning out of the eyelid; Always the lower eyelid
- Developmental or structural
- Acquired or cicatrical
- Intermittent
Developmental/structural ectropion: Aetiology
Mainly in dogs
- Possible genetic basis
- Some ectropion is considered normal in some breeds of dog
- CSx may be absent
Acquired/cicatrical ectropion: Aetiology
- Trauma to the lids → scar formation & skin contraction
- May be caused by periocular surgery or chronic inflammation
- Frequent in horses
This is the same aetiology as entropion
Intermittent ectropion: Summary
- Seen in larger hunting breed of dogs (setters & retrievers)
- Eyelids are normal in the morning; Ectropion seen at night
- Unknown mechanism
- Surgery is contraindicated
Ectropion: Signs to look for
- Lacrimation & conjunctivitis
- Corneal vascularisation in advanced cases
- Eversion of the lower lid
Ectropion: Treatment
Many animals tolerate slight ectropion
Indications for surgery:
- Presence of secondary signs
- If it is desired by the owner
Ectropion: Surgical technique
Modified Kuhnt-Szymanowski method
Ectropion surgery: Postoperative tx
- ABx; NSAIDS; Elizabethan collar
- Suture removal after 10-12 days
Notable lesion seen in the eyelid: Hordeolum
Hordeolum externum or Hordeolum internum
- Externum: Purulent inflam. of a lash follicle & gland of Zeis
- Internum: Purulent inflam. of a tarsal gland
Caused by S. aureus
Hordeolum: Signs to look for
- Focal & painful microabscesses on the lid margin
- Yellowish; up to 10mm in diameter
Hordeolum: Treatment
Medical management / Surgery
Notable lesion seen in the eyelid: Blepharitis
Inflammation of the eyelid
Classified by:
- Aetiology: Bacterial; mycotic; parasitic; allergic
- Location: Unilateral; bilateral; upper; lower; both
- Expansion: Focal; diffuse
Blepharitis: Signs to look for (Acute)
- Pain; blepharospasm; pruritis; alopecia
- Swelling; hyperaemia; sero-purulent discharge
Blepharitis: Signs to look for (Chronic)
- Ulceration & fibrosis
- May have associated conjunctivitis/keratoconjunctivitis
Blepharitis: Laboratory testing available
- Cotton swab sample: Bacteriology
- Scraping: Parasites
- Skin biopsy: Fungi
Blepharitis: Treatment
Dependent on the cause; Elizabethan collar needed
- Bacterial
- Fungal
- Parasitic
- Allergic
Causes of blepharitis: Bacterial infection
Staphylococcus & Streptococcus spp.
- Acute Tx: Hot compress & washing; topical & systemic ABx
- Chronic Tx: Topical & systemic ABx & steroids
Causes of blepharitis: Fungal infection
- Microsporum* & Trichophyton spp.
- Tx: Topical & systemic fungicides
- Avoid contact between the drug and the cornea*
Causes of blepharitis: Parasitic infection
- Demodex* & Sarcoptes spp.
- Tx: Topical & systemic parasiticides
- Avoid contact between the drug and the cornea*
Causes of blepharitis: Allergies
Tx:
- Elimination of the allergen
- Topical & systemic steroids
Traumatic injuries to the eyelid: Signs to look for
- May be just in the skin or full thickness of the lid
- Varying size of laceration
- Fresh injuries: Intensive bleeding
It’s important to evaluate the globe & lacrimal punctas’ condition
Traumatic injury to the eyelid: Treatment
Wound management
- Repair to restore anatomic & functional integrity ASAP after injury
- Untreated injury → Cicatricial entropion/ectropion
Notable lesion seen in the eyelid: Tumour
- Equally common amongst all species
- Malignant or benign; metastasis is rare
Tumour of the eyelid: Signs to look for
- Malignant tumours: Locally invasive → Loss of function & deformity
- Pain; discharge; ulcer; haemorrhage; lacrimation; dry eye surface
Tumour of the eyelid: Treatment
Surgery
Radiotherapy; chemotherapy
