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Third Eyelid Abnormalities/Protrusion 971

• NOTE: use caution when passing suture
blindly through the ventral orbital perios-
VetBooks.ir • CONTRAINDICATION: excision of a prolapsed Diseases and Disorders
teum because inadvertent globe penetration
can cause blinding ocular injury.
gland of the third eyelid. Removal of this
gland may permanently reduce tear function
and often leads to keratoconjunctivitis sicca
months or years after the procedure.
Everted cartilage of the third eyelid:
• Everted cartilaginous tips of the leading edge
of the third eyelid may not require therapy.
• Surgical options for scrolled third eyelid
cartilage:
○ Surgical excision of the bent aspect of the
shaft third eyelid cartilage with the con-
junctiva left to heal by second intention
○ And/or application of low temperature
cautery can be applied to the convex
side of the bent cartilage; causes carti-
lage contraction, straightening affected
THIRD EYELID ABNORMALITIES/PROTRUSION Scrolled cartilage of the third eyelid in a dog. Note the areas
anterior scrolling of the leading edge of the third eyelid. ○ NOTE: excessive application of cautery
can cause overcorrection.
Neoplasia of the third eyelid gland:
○ Various causes and pathophysiology, ○ Schirmer ear test: low values (<15 mm • Local excision, with or without adjunc-
depending on tumor type wetting/minute) may occur with chronic tive therapies (e.g., cryotherapy, radiation
○ Hemangiomas/hemangiosarcomas and prolapsed gland of the third eyelid. therapy, chemotherapy) is dictated by size
squamous cell carcinomas have been ○ Fluorescein stain: ensure there is a lack of and predicted biologic behavior.
associated with UV light exposure. corneal stain uptake to rule out ulceration • Complete excision of the third eyelid is
as a cause of pain because topical steroids indicated for diffuse or malignant neoplasms
DIAGNOSIS are occasionally indicated to reduce of the third eyelid gland.
inflammation before surgical repair • NOTE: all excised samples should be submit-
Diagnostic Overview ted for histopathology.
Most conditions associated with the third eyelid Advanced or Confirmatory Testing • NOTE: an empirical trial of topical
are diagnosed based on clinical appearance, but • Neoplasia of the third eyelid corticosteroids (dexamethasone 0.1% solu-
a complete ophthalmic exam should be done. ○ Obtain a biopsy, taking care to avoid tion or ointment q 6-8h for 10-14 days)
exposing the cartilage of the third eyelid, can be used to differentiate inflammatory
Differential Diagnosis which can cause irritation to the ocular disorders from neoplastic lesions.
Differentials for a mass or swelling of third surface.
eyelid: ○ Palpate the ipsilateral mandibular lymph PROGNOSIS & OUTCOME
• Prolapsed gland of the third eyelid, everted node, and obtain a fine-needle aspirate for
cartilage of the third eyelid, atypical pannus, cytology if enlarged. • Prolapsed gland of the third eyelid: good
and some third eyelid neoplasms ○ Tumor staging and complete third eyelid after surgical repair. Repeated prolapse occurs
• Chemosis excision are indicated for malignant tumors. commonly (up 20%), and attempts at repair
• Onchocerca granuloma • Advanced diagnostic imaging modalities should be repeated. Bulldogs may have a
Differentials for protrusion of the third eyelid: may be indicated if third eyelid protrusion lower success rate than other breeds. Consider
• Pain is suspected to be secondary to orbital disease. referral to an ophthalmologist with repeated
• Orbital disease prolapses.
• Variation in degree of pigmentation of third TREATMENT • Everted cartilage of the third eyelid: good
eyelids. Often, one that is not pigmented after surgical repair. Surgical correction can
appears more obvious than a pigmented third Treatment Overview restore normal anatomic appearance and
eyelid. Medical or surgical therapies are specific to function in most cases.
each third eyelid disorder. • Protrusion of the third eyelid secondary
Initial Database to orbital disease: depends on underlying
• Prolapsed gland of the third eyelid and Acute General Treatment process
everted cartilage of the third eyelid: diagnosis Prolapsed gland of the third eyelid: • Atypical pannus: good prognosis for control
is typically straightforward based on appear- • Expedient surgical repair reduces the likeli- with topical therapy
ance and expected signalment hood of progressive inflammation and loss
• Protrusion of the third eyelid secondary to of tear production. PEARLS & CONSIDERATIONS
Horner’s syndrome: most cases also have • Multiple options for surgical repair exist, and
miosis, ptosis and enophthalmos selection depends on surgeon preference: Comments
• Atypical pannus: diagnosis is typically ○ Imbrication of bulbar conjunctiva over • The gland of the third eyelid should be
straightforward based on appearance and the gland (pocket technique) excised only when neoplasia is present.
expected signalment. ○ And/or suture anchoring to ventral orbital • The bulbar surface of the third eyelid can
• Complete ophthalmic exam (p. 1137) periosteum be examined by retropulsing the globe and
○ Pupillary light reflexes: miosis is often ○ And/or suture anchoring to the cartilage using thumb forceps to gently grasp the
present with Horner’s syndrome of the third eyelid leading edge of the third eyelid and extending

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