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Related Experiment Video

Updated: Mar 18, 2026

Effect of Artificial Tear Formulations on the Metabolic Activity of Human Corneal Epithelial Cells after Exposure to Desiccation
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Tear Break-up Time in High Altitude Areas.

K N Jha1

  • 1Professor of Ophthalmology, Manipal College of Medical Sciences, P.O.Box No.341, Pokhara, Nepal.

Medical Journal, Armed Forces India
|July 14, 2016
PubMed
Summary

High altitude environments can cause abnormal tear film, leading to eye discomfort. A study found 24% of individuals had abnormal Tear Break-up Time (TBUT), indicating ocular issues in these conditions.

Area of Science:

  • Ophthalmology
  • Environmental Medicine

Background:

  • High altitude environments present unique challenges to ocular health.
  • Low humidity, windy conditions, and high UV radiation contribute to tear film abnormalities.

Purpose of the Study:

  • To investigate tear film abnormalities in individuals residing in high altitude areas.
  • To correlate environmental factors with ocular discomfort and conditions like pterygium.

Main Methods:

  • Tear Break-up Time (TBUT) was measured in 100 subjects in Ladakh.
  • Subjects included both local populations and those relocated from plains.

Main Results:

  • 24% of individuals exhibited an abnormal TBUT (< 5 seconds).
  • Symptomatic individuals with abnormal TBUT reported irritation, foreign body sensation, pain, watering, and redness.
Keywords:
High altitude areas (HAA)Tear Break-up Time (TBUT)

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  • Pterygium was observed in 12 individuals, and interpalpebral congestion in 4.

    • Conclusions:

    • A significant percentage (24%) of the high-altitude population demonstrated abnormal tear film function.
    • Environmental factors at high altitudes likely contribute to ocular discomfort and conditions such as pterygium.
    • Ocular surface health requires attention in high-altitude regions due to prevalent environmental stressors.