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Published on: May 2, 2020
The Influence of Tear Film Quality on Visual Function
Snježana Kaštelan1, Ksenija Gabrić2, Maša Mikuličić2
1Department of Ophthalmology, Fundamentals of Medical Skills, School of Medicine, University of Zagreb, Clinical Hospital Dubrava, 10 000 Zagreb, Croatia.
Post-blink blur time (PBBT) shows promise as an objective screening test for dry eye disease (DED). Shorter PBBT and tear film break-up time (TBUT) correlate with DED symptoms, indicating tear film instability impacts vision.
Area of Science:
- Ophthalmology
- Vision Science
- Biomedical Engineering
Background:
- Dry eye disease (DED) prevalence is rising globally, causing ocular discomfort and visual disturbances.
- Accurate DED diagnosis is complex, often requiring specialized tools.
- Tear film instability significantly impacts visual function.
Purpose of the Study:
- To investigate the impact of tear film instability on visual function.
- To evaluate post-blink blur time (PBBT) as an alternative method for assessing tear film stability.
- To explore the association between PBBT and dry eye disease (DED).
Main Methods:
- 62 subjects were divided into DED (n=31) and control (n=31) groups.
- Symptoms assessed via Schein questionnaire and additional questions.
- Post-blink blur time (PBBT) and tear film break-up time (TBUT) measured using Snellen charts.
Main Results:
- Significant differences in average PBBT and TBUT between DED and control groups (p < 0.001).
- Average PBBT: 8.95s (DED) vs 14.66s (Control). Average TBUT: 4.77s (DED) vs 7.63s (Control).
- Strong positive correlation found between PBBT and TBUT (r = 0.455, p < 0.001).
Conclusions:
- Tear film stability is crucial for light refraction and visual optical quality.
- Post-blink blur time (PBBT) shows potential as an objective clinical screening tool for DED.
- PBBT may offer a valuable alternative for assessing tear film stability in DED patients.
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