On tear film breakup (TBU): Dynamics and imaging

Richard J. Braun, Tobin A. Driscoll, Carolyn G. Begley, P. Ewen King-Smith, Javed I. Siddique

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

We report the results of some recent experiments to visualize tear film dynamics. We then study a mathematical model for tear film thinning and tear film breakup (TBU), a term from the ocular surface literature. The thinning is driven by an imposed tear film thinning rate which is input from in vivo measurements. Solutes representing osmolarity and fluorescein are included in the model. Osmolarity causes osmosis from the model ocular surface, and the fluorescein is used to compute the intensity corresponding closely to in vivo observations. The imposed thinning can be either one-dimensional or axisymmetric, leading to streaks or spots of TBU, respectively. For a spatially-uniform (flat) film, osmosis would cease thinning and balance mass lost due to evaporation; for these space-dependent evaporation profiles TBU does occur because osmolarity diffuses out of the TBU into the surrounding tear film, in agreement with previous results. The intensity pattern predicted based on the fluorescein concentration is compared with the computed thickness profiles; this comparison is important for interpreting in vivo observations. The non-dimensionalization introduced leads to insight about the relative importance of the competing processes; it leads to a classification of large vs small TBU regions in which different physical effects are dominant. Many regions of TBU may be considered small, revealing that the flow inside the film has an appreciable influence on fluorescence imaging of the tear film.

Original languageEnglish (US)
Pages (from-to)145-180
Number of pages36
JournalMathematical Medicine and Biology
Volume35
Issue number2
DOIs
StatePublished - Jun 1 2018

Fingerprint

Breakup
Tears
Imaging
Imaging techniques
Thinning
thinning
Fluorescein
Osmolar Concentration
Osmosis
Evaporation
osmosis
evaporation
Optical Imaging
Theoretical Models
Fluorescence
solute
mass balance
fluorescence

All Science Journal Classification (ASJC) codes

  • Neuroscience(all)
  • Modeling and Simulation
  • Biochemistry, Genetics and Molecular Biology(all)
  • Immunology and Microbiology(all)
  • Environmental Science(all)
  • Pharmacology
  • Applied Mathematics

Cite this

Braun, R. J., Driscoll, T. A., Begley, C. G., Ewen King-Smith, P., & Siddique, J. I. (2018). On tear film breakup (TBU): Dynamics and imaging. Mathematical Medicine and Biology, 35(2), 145-180. https://doi.org/10.1093/imammb/dqw023
Braun, Richard J. ; Driscoll, Tobin A. ; Begley, Carolyn G. ; Ewen King-Smith, P. ; Siddique, Javed I. / On tear film breakup (TBU) : Dynamics and imaging. In: Mathematical Medicine and Biology. 2018 ; Vol. 35, No. 2. pp. 145-180.
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Braun, RJ, Driscoll, TA, Begley, CG, Ewen King-Smith, P & Siddique, JI 2018, 'On tear film breakup (TBU): Dynamics and imaging', Mathematical Medicine and Biology, vol. 35, no. 2, pp. 145-180. https://doi.org/10.1093/imammb/dqw023

On tear film breakup (TBU) : Dynamics and imaging. / Braun, Richard J.; Driscoll, Tobin A.; Begley, Carolyn G.; Ewen King-Smith, P.; Siddique, Javed I.

In: Mathematical Medicine and Biology, Vol. 35, No. 2, 01.06.2018, p. 145-180.

Research output: Contribution to journalArticle

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