Tear fluid is an exciting and growing area for clinical research. The optimal method for tear collection in animals should be safe, minimally invasive, rapid, and cost-effective. Ophthalmic surgical sponges fulfill all of these criteria as they are developed for use on the ocular surface, have a rapid and large absorptive capacity, are relatively inexpensive and, following centrifugation, provide tears that are directly available for analysis.
The present study shows that polyvinyl acetal (PVA) sponges are better than cellulose-based sponges given their superior recovery following centrifugation. These sponges could facilitate routine analysis of tear fluid in dogs and cats, although further studies are needed to evaluate the quality of tears obtained with this method.