Qualitative assessment of tear dynamics with fluorescein profilometry

• Published in: Contact lens & anterior eye Vol. 40; no. 4; pp. 208 - 212
• Main Authors: Garaszczuk, Izabela K., Iskander, D. Robert
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.08.2017
• Subjects: Adult; Aged; Blinking - physiology; Dry Eye Syndromes - diagnosis; Dry Eye Syndromes - metabolism; Dry Eye Syndromes - physiopathology; Female; Fluorescein - administration & dosage; Fluorescein - pharmacokinetics; Fluorescein profilometry; Fluorescent Dyes - administration & dosage; Fluorescent Dyes - pharmacokinetics; Healthy Volunteers; Humans; Male; Middle Aged; Ophthalmology; Tear clearance; Tear film dynamics; Tear fluorescein washout rate; Tears - physiology; Young Adult; Fluorescein profilometry; Tear fluorescein washout rate; Tear clearance; Tear film dynamics
• ISSN: 1367-0484; 1476-5411; 1476-5411
• DOI: 10.1016/j.clae.2017.04.004

•Tear turnover is the summation of tear secretion, exudation, evaporation, drainage and corneal or conjunctival permeability.•The most common way to assess tear turnover is to follow the elution of dye by monitoring decreased fluorescence over time.•We show that fluorescein profilometry can be utilized for qualitative observation of tear turnover on the entire surface of the eye.•Statistically significant correlations were found between tear fluorescein wash-out rate and other measures of tear film. To describe a new methodology for tear-film dynamics assessment by observing fluorescein decay rate over time and to understand the relationship between the newly defined tear fluorescein washout rate (TFWR) and other measures of the tear film behaviour. Forty subjects (24F/16M) aged (mean±standard deviation) 31.8±14.2years volunteered for the study. It consisted of the review of medical history, McMonnies questionnaire (McMQ), slit lamp examination, and TFWR using a newly-developed fluorescein profilometry. The repeatability of TFWR measurements was assessed. TFWR estimates were contrasted against patient age, McMQ score, daytime, fluorescein tear film break-up time (FTBUT), tear meniscus height (TMH) and blink frequency. Mean repeatability of the method was 28.13±9.59%. The group mean TFWR was 39±23% at 30-s mark after the beginning of measurements, ranging from 1.4% to 83%. This indicates that TFWR is highly subject-dependent. Statistically significant correlations were found between the percentage TFWR and McMQ score (r2=0.214, p=0.001) as well as FTBUT (r2=0.136, p=0.009). No statistically significant correlations were found between TFWR and age, daytime, TMH, and blink frequency. Fluorescein profilometry allows clinicians to follow dynamic changes in the tear film on the entire ocular surface and may be used for qualitative assessment of the tear film dynamics.