Tear film dynamics and lipid layer characteristics--effect of age and gender

Cont Lens Anterior Eye. 2010 Aug;33(4):176-82. Epub 2010 Mar 3.

Tear film dynamics and lipid layer characteristics--effect of age and gender.

Maïssa C, Guillon M.

Source

OTG Research & Consultancy, London, UK. cmaissa@otg.co.uk

Abstract

PURPOSE:

Dry eye disease is significantly more prevalent in older subjects and among them more marked in women than men. Further, it is established that the tear film dynamics of dry eye sufferers is different to that of normal. It is therefore postulated that the greater prevalence of dry eye problems with advancing age is at least in part related to poorer tear film dynamics.

METHODS:

Tear film dynamics (non-invasive break up time) and lipid characteristics (lipid layer thickness and contamination) were assessed using the Tearscope lighting system.

RESULTS:

160 Subjects less than 45 years old and 58 subjects aged 45 years or more formed the study populations. The tear film stability was mostly influenced by age; the break up time was statistically significantly shorter for the older age group (p < 0.001). The lipid layer was also significantly thinner (p = 0.013) for the subjects aged 45 years or older with a very marked synergic effect of age and gender. The lipid layer of older women was significantly thinner and more contaminated than that of younger women (p = 0.002 and < 0.001) and of older men (p = 0.034 and 0.004).

CONCLUSIONS:

Aging of the tear film is characterised by its destabilisation associated with significant changes in the tear lipid layer producing less protection from evaporation in the older population; the observed changes are more marked in women than in men. The findings have significant implications for the management of presbyopic dry eye sufferers, for whom decreasing evaporative problems is essential.

2010 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

Cont Lens Anterior Eye. 2010 Apr;33(2):76-82. Epub 2009 Dec 6.

Effect of castor oil emulsion eyedrops on tear film composition and stability.

Maïssa C, Guillon M, Simmons P, Vehige J.

Source

OTG Research & Consultancy, London, UK. cmaissa@otg.co.uk

Abstract

PURPOSE:

An emulsion eyedrop containing castor oil has been shown to modify the tear film lipid layer and increase tear film stability. The primary objectives of this investigation were to measure the prevalence of castor oil in the tear fluid over time and quantify the effects on the lipid layer. A secondary objective was to quantify the initial effects on ocular symptomatology.

METHODS:

The investigation was an open label pilot study on 5 normal and 10 dry eye subjects. A single eyedrop (Castor oil emulsion, Allergan) was instilled in each eye; the tear film appearance and composition were monitored for 4h via in vivo visualisation using the Tearscope and post in vivo tear samples analysis by HPLC.

RESULTS:

Combined results for both normal and dry eye subjects showed that castor oil was detected up to 4h after a single eyedrop instillation and associated with an increase in the level of tear film lipid. The relative amount of various lipid families was also changed. An increase in tear lipid layer thickness was significant up to one hour post-instillation for the symptomatic sub-population. The changes in tear film characteristics were associated with significantly lower symptoms up to four hours post-instillation for the symptomatic sub-population.

CONCLUSION:

This pilot investigation showed that castor oil eyedrops achieved a residence time of at least four hours post-instillation, producing a more stable tear film and an associated significant decrease in ocular symptoms over the entire follow-up period for the symptomatic subjects.

2009 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.