Lacrimal Production of Cats: Schirmer Tear Test, Phenol Red Thread Tear Test and Endodontic Absorbent Paper Point

Abstract

The lacrimal production measurement is part of the ophthalmic semiotechnique in clinical routine of small animals and the Schirmer Tear Test (STT) is the most used tool for lacrimal production assessment in cats. There are few studies in the literature using alternative methods that aim optimizing the results and reduce stress of manipulation or discomfort caused by the test. Thus, the aim of this study was to determine the values of lacrimal production in cats through Schirmer tear test type-1 (STT1), Phenol red thread tear test (PRTT) and the Endodontic absorbent paper point tear test (EAPPTT). Twenty two cats, eleven males and eleven females, castrated, without evidence of clinical and ophthalmic disorder and assessed in domiciliary environment were used in this experiment. STT1 caused the major discomfort, followed by EAPPTT and PRTT. There were no significant differences between right and left eye and gender in all tests. The mean (± SD) STT1 value was 16.77 ± 5.10 mm/min., PRTT value was 27.95 ± 4.79 mm/15 sec. and EAPPTT value was 13.64 ± 2.67 mm/15 sec. The results obtained may help in the diagnosis of quantitative disorders in the aqueous portion of the tear film, through alternative tests, as well as in the guiding for selecting the most suitable test.

Comparison of the Schirmer tear test I values after placement in ventral and dorsal conjunctival fornices in healthy cats

“…7 Some cats may experience discomfort because of the duration of contact of the STT strips with the cornea. 8 The cats tolerated the STT placement well in both the ventral and dorsal conjunctival fornices. As previously described in dogs, 5 the placement of the strips in the ventral conjunctival fornix was associated with greater STT values than the dorsal placement of the strips in both the non-brachycephalic and brachycephalic cats in our study.…”

“…7 Some cats may experience discomfort because of the duration of contact of the STT strips with the cornea. 8…”

Comparison of Electrolyte Composition and Crystallization Patterns in Bird and Reptile Tears

“…Studies on bird and reptile ocular surface components have shown differences in the lacrimal apparatus, tear production and palpebral incursion frequency among species ( 16 , 17 ); however, there are only a few qualitative descriptions of tears, mainly of their microcomponents ( 18 ). The elucidation of tear composition can help in the understanding of the homeostasis process played by this specific body fluid and in the diagnosis of ocular surface diseases.…”

Evaluation of tear production in juvenile opossum using three different methods

“…However, features regarding execution have been reported, and it was pointed out that the use of EAPPTT allowed less contact with the vibrissae. For cats, Schirmer tear test caused greater discomfort (Oriá et al 2015a), when compared the three tests. For opossums, mSTT has been considered easier than PRTT for being more rigid strip, but even the modified method was wider than the EAPPTT, causing more difficulties for execution.…”

“…PRTT-related performance difficulties were not reported in equines and cats, although these animals have abundance in vibrissae. Possibly, due to the size of the eyelid cleft (Sindak et al 2010, Oriá et al 2015a. When comparing different methods of tear production evaluation in an experimental model, EAPPTT is reported as a method that causes less discomfort to the ocular surface (Lima et al 2010).…”