Cyst Formation in the Canine Third Eyelid

In the Literature

Barbé C, Raymond-Latron I, Mias G-P, Charron J, Goulle F. Marsupialization of a cyst of the nictitating membrane in three dogs. Vet Ophthalmol. 2017;20(2):181-188.

 ... The Research

Prolapsed gland of the nictitating membrane (NM) is the most common disorder affecting the third eyelid of dogs presented to small animal practitioners. Certain breeds (eg, English bulldog, Neapolitan mastiff, cocker spaniel, beagle, Boston terrier) are disproportionately affected. The exact etiology is unknown.

The third eyelid plays a vital role in quantitative and qualitative tear film dynamics and serves as an additional physical barrier protection to the cornea. Preservation via surgical repair is imperative. The most common technique is the Morgan pocket technique. A rarely reported complication of this surgery is cyst formation. In dogs with this complication, a fluctuant, somewhat translucent swelling protrudes from the bulbar surface of the NM. The fluid is composed of nonseptic lacrimal secretions.

This study described surgical marsupialization in which NM cysts were opened using sharp and blunt dissection via a horizontal, linear incision over the cystic mass on the ventral palpebral surface. After opening and flushing, marsupialization was achieved by suturing the cyst wall to the adjacent NM conjunctiva in a simple interrupted suture pattern using absorbable 6-0 suture. Marsupialization resulted in excellent long-term tear film results for affected dogs.

Marsupialization as described in this case series appears to be a safe and effective treatment for cyst formation following Morgan pocket repair.

… The Takeaways

Key pearls to put into practice:

• To preserve corneal health and vision in dogs, clinicians should strive to repair—rather than remove—a prolapsed gland of the NM.

• A cyst of the nictitans should be suspected in cases with history of repaired prolapsed gland of the NM or NM trauma. It should also be suspected if a dog is presented with an enlarged NM and if a soft, hyperemic, somewhat translucent, subconjunctival mass is detected protruding from the bulbar surface of the NM. Fine needle-aspiration can reveal nonseptic lacrimal fluid.

• Marsupialization on the palpebral aspect of the NM as described in this case series was curative with preservation of NM function and excellent long-term cosmetic results.