Canine distichiasis cryoepilation using a liquid nitrogen-cooled, closed probe transconjunctival triple-freeze technique: Outcomes in 125 dogs (234 eyes).

Purpose: To describe a simple cryosurgical technique for treating canine distichiasis, its success rate and any associated complications.
Methods: Clinical records from canine patients undergoing treatment for distichiasis using a specific cryotherapy technique were retrospectively reviewed. The technique employed a triple freeze-thaw cycle via a transconjunctivally applied, liquid nitrogen-cooled, 2-mm diameter closed cryoprobe.
Results: The cryotherapy technique was employed in 125 dogs with distichiasis over a period of 13 years, with 109 (87%) bilaterally and 16 (13%) unilaterally affected, totaling 234 eyes. The mean age at diagnosis was 1.9 years (4 months to 7.5 years), with Staffordshire bull terriers the most common breed (31%). Treatment was deemed successful if clinical signs related to distichiasis resolved, including blepharospasm, conjunctival hyperemia and excess lacrimation. A single triple-freeze cryotherapy treatment eliminated distichiae in 195/234 (83%) eyes at a mean follow-up of 4 months (2 weeks to 10 years). Minor recurrence of distichiae in previously treated regions was observed in 39/234 (17%) eyes. Repeat cryotherapy was required in 25/234 (11%) eyes, with the remaining eyes asymptomatic. The two most common postoperative complications were mild to moderate eyelid swelling in all eyes immediately following surgery and eyelid margin depigmentation in 59/234 eyes (25%) between two and 4 weeks postoperatively, both of which were temporary.
Conclusion: This cryotherapy technique for treating canine distichiasis is relatively simple and safe to perform, has a high success rate and a low recorded complication rate, but would benefit from further assessment of any potential detrimental effects on qualitative tear film components.
(© 2023 American College of Veterinary Ophthalmologists.)