An investigation into the development of qualitative tear film disorders in dogs following cryoepilation for distichiasis.

Abstract

OBJECTIVE: The aim of this prospective study was to compare tear film quality between dogs who have previously undergone cryoepilation for distichiasis to a reference population. ANIMALS STUDIED: Nine dogs (17 eyes) were recruited after surgery and were compared to a reference population of 21 dogs (42 eyes). PROCEDURES: Canine patients who had previously undergone cryoepilation for distichiasis for a minimum of 1&#xa0;month prior to examination were recruited. A complete ophthalmic examination was performed by an ABVO resident (BDR), with additional tear tests, including tear film interferometry, infra-red meibography, and a tear film break-up time (TFBUT) performed. The tear test results were compared to a reference population obtained from client-owned dogs with no history of ophthalmic complaints, a normal ophthalmic examination performed by an ABVO resident (BDR) and a Schirmer Tear Test-1&#x2009;>&#x2009;15&#x2009;mm/min. Statistical analysis was performed of the results obtained. RESULTS: The treated group was significantly more affected with meibomian gland dropout (MG-dropout) in 11/17 (64.7%) cases, compared to the reference population of 2/21 (9.5%) (p&#x2009;<&#x2009;.01). The treated group had an odds ratio of 23.8 to develop MG-dropout compared to the reference population (p&#x2009;<&#x2009;.01). Tear film breakup time (TFBUT) was significantly shorter in the treatment group (5.8&#x2009;&#xb1;&#x2009;2.6&#xa0;s) compared to the reference population (10.1&#x2009;&#xb1;&#x2009;1.1&#xa0;s) (p&#x2009;<&#x2009;.001). In the treatment group, 12/17 (70.5%) of treated eyes had a TFBUT&#x2009;<&#x2009;5&#xa0;s compared to 2/21 (9.5%) of the reference population. CONCLUSION: Cryoepilation for distichaiasis appears to be a risk factor for developing MG-dropout and qualitative tear film disorders post-operatively in canines.