• 1. Sebbag L, Pesavento PA, Carrasco SE, et al. Feline dry eye syndrome of presumed neurogenic origin: a case report. JFMS Open Rep 2018;4:2055116917746786.

    • Search Google Scholar
    • Export Citation
  • 2. Lim CC, Reilly CM, Thomasy SM, et al. Effects of feline herpesvirus type 1 on tear film break-up time, Schirmer tear test results, and conjunctival goblet cell density in experimentally infected cats. Am J Vet Res 2009;70:394403.

    • Search Google Scholar
    • Export Citation
  • 3. Sebbag L, Kass PH, Maggs DJ. Reference values, intertest correlations, and test-retest repeatability of selected tear film tests in healthy cats. J Am Vet Med Assoc 2015;246:426435.

    • Search Google Scholar
    • Export Citation
  • 4. García-Porta N, Mann A, Sáez-Martínez V, et al. The potential influence of Schirmer strip variables on dry eye disease characterisation, and on tear collection and analysis. Cont Lens Anterior Eye 2018;41:4753.

    • Search Google Scholar
    • Export Citation
  • 5. Swinscow T, Campbell M. Correlation and regression. In: Campbell MJ, Swinscow TDV, eds. Statistics at square one. 11th ed. Hoboken, NJ: Wiley-Blackwell, 2009;119132.

    • Search Google Scholar
    • Export Citation
  • 6. Mochel JP, Gabrielsson J, Collard W, et al. Animal Health Modeling & Simulation Society: a new society promoting model-based approaches in veterinary pharmacology. J Vet Pharmacol Ther 2013;36:417419.

    • Search Google Scholar
    • Export Citation
  • 7. Mochel JP, Fink M, Peyrou M, et al. Pharmacokinetic/pharmacodynamic modeling of renin-angiotensin aldosterone biomarkers following angiotensin-converting enzyme (ACE) inhibition therapy with benazepril in fogs. Pharm Res 2015;32:19311946.

    • Search Google Scholar
    • Export Citation
  • 8. Riviere JE, Gabrielsson J, Fink M, et al. Mathematical modeling and simulation in animal health. Part I: moving beyond pharmacokinetics. J Vet Pharmacol Ther 2016;39:213223.

    • Search Google Scholar
    • Export Citation
  • 9. Bon C, Toutain PL, Concordet D, et al. Mathematical modeling and simulation in animal health. Part III: using nonlinear mixed-effects to characterize and quantify variability in drug pharmacokinetics. J Vet Pharmacol Ther 2018;41:171183.

    • Search Google Scholar
    • Export Citation
  • 10. Pelligand L, Soubret A, King JN, et al. Modeling of large pharmacokinetic data using nonlinear mixed-effects: a paradigm shift in veterinary pharmacology. A case study with robenacoxib in cats. CPT Pharmacometrics Syst Pharmacol 2016;5:625635.

    • Search Google Scholar
    • Export Citation
  • 11. Macdougall J. Analysis of dose-response studies—Emax model. In: Ting N, ed. Dose finding in drug development. New York: Springer, 2006;127145.

    • Search Google Scholar
    • Export Citation
  • 12. Botelho SY, Hisada M, Fuenmayor N. Functional innervation of the lacrimal gland in the cat. Origin of secretomotor fibers in the lacrimal nerve. Arch Ophthalmol 1966;76:581588.

    • Search Google Scholar
    • Export Citation
  • 13. Powell CC, Martin CL. Distribution of cholinergic and adrenergic nerve fibers in the lacrimal glands of dogs. Am J Vet Res 1989;50:20842088.

    • Search Google Scholar
    • Export Citation
  • 14. Whitwell J. Role of the sympathetic in lacrimal secretion. Br J Ophthalmol 1961;45:439445.

  • 15. Dartt DA. Neural regulation of lacrimal gland secretory processes: relevance in dry eye diseases. Prog Retin Eye Res 2009;28:155177.

    • Search Google Scholar
    • Export Citation
  • 16. Proctor GB, Carpenter GH. Salivary secretion: mechanism and neural regulation. Monogr Oral Sci 2014;24:1429.

  • 17. Uhl LK, Saito A, Iwashita H, et al. Clinical features of cats with aqueous tear deficiency: a retrospective case series of 10 patients (17 eyes). J Feline Med Surg 2019;21:944950.

    • Search Google Scholar
    • Export Citation
  • 18. Davis K, Townsend W. Tear-film osmolarity in normal cats and cats with conjunctivitis. Vet Ophthalmol 2011;14(suppl 1):5459.

  • 19. Williams DL. Analysis of tear uptake by the Schirmer tear test strip in the canine eye. Vet Ophthalmol 2005;8:325330.

  • 20. Veith LA, Cure TH, Gelatt KN. The Schirmer tear test in cats. Mod Vet Pract 1970;51:4849.

  • 21. Craig JP, Nelson JD, Azar DT, et al. TFOS DEWS II Report executive summary. Ocul Surf 2017;15:802812.

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Investigation of Schirmer tear test-1 for measurement of tear production in cats in various environmental settings and with different test durations

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  • 1 1Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA 50011.
  • | 2 2Lloyd Veterinary Medical Center, College of Veterinary Medicine, Iowa State University, Ames, IA 50011.
  • | 3 3Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA 50011.
  • | 4 4Cat Clinic of Iowa City, Iowa City, IA 52240.

Abstract

OBJECTIVE

To assess reliability of the Schirmer tear test-1 (STT-1) for measurement of tear production in cats in various environments, investigate whether sympathetic stimulation impacts measurements, and determine whether meaningful conclusions regarding lacrimation in cats can be drawn from STT-1 measurements obtained with STT strip placement for < 1 minute.

ANIMALS

176 cats examined in a private practice (n = 100), a feral cat clinic (56), or a veterinary teaching hospital (20).

PROCEDURES

The STT-1 was performed in both eyes of each cat. Measurements were recorded at 10− or 30-second intervals for 1 minute. Cats at the teaching hospital were tested once in a quiet examination room (unstimulated conditions) and once in the same room with loud prerecorded noises (stimulated conditions), with a 30-minute interval between tests and evaluation of cats’ heart rates before and after STT-1. Data were analyzed with parametric statistical tools and a nonlinear mixed-effect model.

RESULTS

30− and 60-second STT-1 measurements were significantly correlated (r = 0.94). The STT-1 measurements did not differ under nonstimulated versus stimulated conditions, despite significant changes in heart rates that indicated sympathetic stimulation. A hyperbolic model of STT-1 kinetics was validated, allowing for extrapolation of measurements obtained in < 60 seconds and generation of reference values (95% predictive intervals) for various test durations. Median (95% predictive interval) 30− and 60-second STT-1 measurements were 9.1 mm (4.8 to 15.6 mm) and 14.3 mm (8.2 to 22.3 mm), respectively.

CONCLUSIONS AND CLINICAL RELEVANCE

The STT-1 was a reliable diagnostic test in all settings; results were not affected by sympathetic stimulation, and a shorter duration of testing could be considered in selected cases.

Abstract

OBJECTIVE

To assess reliability of the Schirmer tear test-1 (STT-1) for measurement of tear production in cats in various environments, investigate whether sympathetic stimulation impacts measurements, and determine whether meaningful conclusions regarding lacrimation in cats can be drawn from STT-1 measurements obtained with STT strip placement for < 1 minute.

ANIMALS

176 cats examined in a private practice (n = 100), a feral cat clinic (56), or a veterinary teaching hospital (20).

PROCEDURES

The STT-1 was performed in both eyes of each cat. Measurements were recorded at 10− or 30-second intervals for 1 minute. Cats at the teaching hospital were tested once in a quiet examination room (unstimulated conditions) and once in the same room with loud prerecorded noises (stimulated conditions), with a 30-minute interval between tests and evaluation of cats’ heart rates before and after STT-1. Data were analyzed with parametric statistical tools and a nonlinear mixed-effect model.

RESULTS

30− and 60-second STT-1 measurements were significantly correlated (r = 0.94). The STT-1 measurements did not differ under nonstimulated versus stimulated conditions, despite significant changes in heart rates that indicated sympathetic stimulation. A hyperbolic model of STT-1 kinetics was validated, allowing for extrapolation of measurements obtained in < 60 seconds and generation of reference values (95% predictive intervals) for various test durations. Median (95% predictive interval) 30− and 60-second STT-1 measurements were 9.1 mm (4.8 to 15.6 mm) and 14.3 mm (8.2 to 22.3 mm), respectively.

CONCLUSIONS AND CLINICAL RELEVANCE

The STT-1 was a reliable diagnostic test in all settings; results were not affected by sympathetic stimulation, and a shorter duration of testing could be considered in selected cases.

Supplementary Materials

    • Supplementary Appendix s1 (PDF 94 kb)
    • Supplementary Figure s1 (PDF 280 kb)
    • Supplementary Figure s2 (PDF 452 kb)
    • Supplementary Table s1 (PDF 58 kb)
    • Supplementary Table s2 (PDF 92 kb)
    • Supplementary Table s3 (PDF 54 kb)

Contributor Notes

Dr. Uhl's present address is Veterinary Teaching Hospital, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523.

Address correspondence to Dr. Sebbag (lsebbag@iastate.edu).