What are evaporative dry eyes?
Evaporative dry eyes are caused by a compromised, i.e. an unstable or incomplete lipid layer. The lipid layer is the outermost layer of the tear film and serves to protect against the premature evaporation of the tear. However, the renewal of the lipid layer depends on the blink.
A compromised lipid layer leads to excessive evaporation of the underlying aqueous phase Fig. 1 or to watery eyes because the lipid phase can no longer stabilise the aqueous phase Fig. 2.
In the majority, i.e. almost 90 % of cases, this evaporative form is causally involved in dry eyes1. Typical symptoms associated with a compromised lipid layer are
- watery eyes
- burning sensation
- reddened and painful eyelid edges
- symptoms that are more pronounced in the morning
1 Tong L. et al. Invest Ophthalmol Vis Sci 2010, 51: 3449-3454.
Causes of a compromised lipid layer
The evaporative dry eye can be triggered by external (extrinsic) as well as endogenous (intrinsic) factors.
Intrinsic factors causing a deficiency in the tear film’s lipid layer include a malfunctioning of the lipid-producing meibomian glands positioned in the eyelid margins (meibomian gland dysfunction or MGD) and inflammation of the lid margins (blepharitis). In addition, a malfunctioning eyelid, the intake of medication and a hormonal imbalance (e.g. the menopause) may be the underlying cause for evaporative dry eyes.
The use of digital media with its associated reduced blinking rate (see digital eye stress), wearing of contact lenses and use of preserved eye drops are examples of extrinsic factors that can lead to a compromised lipid layer.
Treating evaporative dry eyes
The conventional treatment of a compromised lipid layer is based on oil or lipid-containing eye drops, which aim to replace the impaired or lacking lipid layer.
Fact is: the majority of those affected suffer from evaporative dry eyes. In contrast, however, predominantly dry eye products are sold that only replace the aqueous phase and thus do not address a compromised lipid layer.
EvoTears®: The next step in the treatment of dry eyes
With EvoTears®, a gap in the treatment of dry eyes due to the evaporative form has been closed. The EvoTears® products take over the function of the lipid layer and thus specifically address the problem of a compromised lipid layer. As a result, they offer effective protection against evaporation and are also very well tolerated, thanks to the absence of additives.
EvoTears® – Effective protection against evaporation and good tolerability for patient satisfaction!
EvoTears® – The unique* protection against evaporation.
* due to perfluorohexyloctane and being water-free
Header graphic: photoCD – stock.adobe.com