Eye Health: Prevention Against the Risks of Summer. Interview with Dr. Domenico Arena

The summer season can put your eye health at risk. Not only because of exposure to the sun's ultraviolet rays, as is the case for the skin, but also because of other external agents such as heat – resulting in poor hydration – or wind; factors that this year can raise awareness even more, given the long lockdown to which the coronavirus has forced many people.

In summer the eyes need careful and adequate protection, even if you do not expose yourself to the sun or do not go on vacation.

We asked Dr. Domenico Arena, ophthalmology specialist at UPMC Salvator Mundi International Hospital, for some advice.

You risk neglecting the well-being of the eyes even if you stay at home or in the car or in the office. Is it true that sudden changes in temperature, for example, caused by air conditioning or dehumidifier, are harmful?

Although apparently delicate organs, the eyes are equipped with physiological and natural protection systems against aggression by biological or physico-chemical external agents: the first bulwark, if we exclude the mechanical effect of eyelid winking, is the tear film that is all the more effective in this action the more "physiological" in its 3 components: lipid, aqueous and mucomimetic. Therefore, an alteration of the percentage balance of these 3 elements, potentially, induces an alteration of its functional characteristics (optical, rheological, thinner, antibiotic, UV filtering etc.) that contribute to comfort and well-being especially on the surface. Unfortunately, there are many local pathologies (blepharitis and conjunctivitis of any nature, outcomes of trauma or surgery) or systemic (rheumatic / autoimmune diseases, diabetes, hormonal dysregulations) that affect this balance; in other cases environmental factors, especially with regard to eyes predisposed to the pathologies on exposed, trigger a cascade of events that leads to surface discomfort. In this perspective, the "Evaporative Dry Eye" comes into play, that is the reduction of the tear aqueous layer for prolonged exposure with reduced winking (video terminal operators), for environments excessively dehumidified by air conditioning systems, for excessive ventilation, especially direct or for a significant increase in ambient temperature. The quantitative tear deficit induces an increase in tear density (hyperosmolarity) that triggers cellular suffering with the release of cyto-chemical mediators of inflammation creating a vicious circle that tends to chronicization.

The sun's ultraviolet rays are the number 1 enemies of eye health. When you are exposed to the sun, how can we protect your eyes in the best way? What basic requirements must good sunglasses have in order to really be an effective protection for the eyes? And for those who need prescription lenses?

Let's clarify some assumptions: ultraviolet (UV) rays are the electromagnetic radiation of the visible spectrum at a lower wavelength (therefore more energetic) that go, within the perceived, from 380 to 500 nanometers; we recognize the UV-C that are totally blocked by the atmosphere, the UV-B that for 80-90% are absorbed by ozone and for the rest totally by cornea and crystalline and finally the UV-A that, although filtered, in good part manage to reach the retina triggering for chronic exposure (especially in the absence of appropriate anti-oxidant protection: elderly, smokers, malnutrition, diabetes etc)a photochemical damage. It follows that the most effective protection consists in "filtering" the residual, but potentially pathogenic, share of UV that reach the diopter media and then equip yourself with a sunglasses that as such is a real PPE (disposi1vo of personal protection).The lenses contain filters that prevent the penetration of UV rays, but the filtering capacity depends on the type of filter. Generally there are 4 classes or categories with increasing filtering power (it is useless in Scandinavia to use the same filter useful for the equator), better if associated with a "polarizing" treatment against acute reflexes. Generally in our latitudes from May to October it is useful to use the 3rd class, but if you go for a long time to the sea (especially by boat where you are exposed to direct and reflected radiation) or in the mountains (or on the snow) it is better to take advantage of a Category 4.The prescription for intermediate categories also depends very much on the skin phototype of the patient or on the presence or absence of individual photosensitivity. It is advisable that good sunglasses have wide lenses in order to also protect the skin area around the eyes and possibly enveloping. Those who use prescription lenses can have a personalized sunglasses "built" on their visual defect.

Is it a rule valid for everyone or for those with different vision problems are different sunglasses necessary?

It is not a rule valid for everyone, for example people with light phototype and / or light eyes are more sensitive to radiation, as well as individuals suffering from photosensitivity or macular pathologies, for whom, after an eye examination, the correct sunscreen may be prescribed.

Is it good to wear them even in the shade?

In case of shading in very irradiated surrounding environments I would say yes.

The main risk is dry eyes which can be caused by poor hydration in the face of high temperatures. How can you fight?

Exclusively with artificial tears that are for the most part solutions of hyaluronic acidat different concentrations, but those useful for a first "over-the-counter" approach are at0.15-0.20% better if without preservatives (single-dose or multidose without preservatives), 3-4 times a day for several days even with improved symptoms.

Can the diet help maintain the well-being of the eye as well?

Sure. Especially from the neurosensory point of view through the intake of carotenoids witha diet rich in colorful fruits and vegetables and Omega 3-6 fatty acids with the consumption of fish(especially "blue and pink"). In case of pre-existing pathologies or reduced intake, it is advisable, on the advice of the ophthalmologist, to take specific supplements.

Conjunctivitis is another risk that summer brings with it. Today a more delicate topic than ever given that it is also counted among the symptoms of the coronavirus. What indication can you give in this regard?

Summer conjunctivitis are mainly "viral" conjunctivitis and generally caused by harmless viruses of the Adenovirus group which, in winter, are responsible for the common pharyngitis and always self-limiting. The new coronavirus (SARS COV2) may also be responsible for conjunctivitis, but only in 0.8% of those infected and in an even smaller percentage as a symptom of onset. If, however, in the pandemic phase a conjunctivitis is associated with a feverish state >37.5 ° and / or respiratory symptoms, it is good to refer not to an ophthalmologist but to the bodies responsible for anti-COVID health surveillance.

Generally what advice could you give to protect your eyes from any potential enemy?

Always keep your eyes healthy and functionally efficient with periodic eye screenings.