Parotid duct transposition

From Dog
Unresponsive keratoconjunctivitis sicca, the primary indicator for parotid duct transposition[1]

Parotid duct transposition is a surgical procedure indicated for keratoconjunctivitis sicca (dry eye) in dogs[2]caused by inadequacy of the lacrimal drainage system.

This surgical procedure is also indicated for sialorrhea, where disturbances to the swallowing mechanism results in excessive salivation. In this disease, the parotid duct opening is translocated to the glossopalatine arch within the fauces[3].

The parotid duct carries saliva from the parotid salivary gland into the mouth and is surgically transposed to the lower puncta of the eye to facilitate eye lubrication. A routine skin incision is made across the cheek and the duct is dissected out and the extremity re-directed towards the eye and sutured into an opening in the lower conjunctiva.

Disadvantages of ductal transposition are that saliva is not the same composition as aqueous tears, so lubrication of the eye is sometimes complicated by mineral deposition on the cornea and eyelids. As well, the dog must be stimulated to salivate frequently.

Serious complications rarely occur but reports of parotid duct sialocoeles, postenucleation orbital sialoceles[4] and secondary cicatrization and obstruction of the duct have been noted.

Excessive tear formation post operative, leading to blephaprospasm, epiphora, dermatitis and keratitis, may be managed with partial ligation of the parotid duct[5].

With experience surgical techniques, the success rate of this procedure is very good, with significant improvement in ocular comfort, number of daily topical treatments, ocular wetness, and postoperative vision[6].

References

  1. Animal Eye Care
  2. Herrera HD et al (2007) Severe, unilateral, unresponsive keratoconjunctivitis sicca in 16 juvenile Yorkshire Terriers. Vet Ophthalmol 10(5):285-288
  3. Ozgenel GY et al (2000) An experimental study of bilateral repositioning of the Stensen's duct orifices with autologous vein and artery grafts in dogs. Br J Plast Surg 53(2):106-108
  4. Guinan J et al (2007) Postenucleation orbital sialocele in a dog associated with prior parotid duct transposition. Vet Ophthalmol 10(6):386-389
  5. Schilke HK & Sapienza JS (2012) Partial ligation of the transposed parotid duct at the level of the parotid gland for excessive salivary secretions. Vet Ophthalmol 15(6):411-416
  6. Rhodes M et al (2012) Parotid duct transposition in dogs: a retrospective review of 92 eyes from 1999 to 2009. Vet Ophthalmol 15(4):213-222