With Halloween just around the corner, thousands of people are ready to complete their costume with colored or particular contact lenses, capable of radically transforming their gaze: from the white and yellow eyes of the living dead to the pupils of a vampire. But behind the undisputed scenic effect lies a real risk to eye health.
According to Sofía Rendo González, a researcher specializing in optics and optometry at the Universidade de Santiago de Compostela, and her colleagues Justo Arines and Nery García Porta who wrote an article in The Conversation, cosmetic contact lenses can cause irritation, infections, corneal ulcers and, in the most severe cases, even lead to blindness.
Materials and safety: an often underestimated aspect
Disguise lenses are easily available in stores and online, but their quality is often uncertain. Studies have highlighted the presence of unauthorized pigments and substances, such as chlorine and iron, which can cause burning, allergies and increase the possibility of eye infections.
García Porta points out that pigments can promote microbial adhesion, increasing the risk of keratitis, a painful corneal infection that, if left untreated, can progress to ulcers and vision loss.
Purchasing lenses from authorized retailers and following the instructions of opticians and optometrists is essential, in fact we are talking about regulated medical devices that must comply with rigorous safety standards, such as those established by the AEMPS in Spain.
The most common dangers
Many users of cosmetic lenses are unaware of the risks and often make serious mistakes when using them, such as cleaning them or storing them in water instead of special solutions. The water may contain dangerous microorganisms, such as Acanthamoeba, responsible for serious infections. The lens case must also be sanitized properly, and the solutions should not be used for extended periods.
Experts warn that complications can range from simple irritation to permanent loss of vision and it is best to consult an eye doctor immediately in case of any abnormal symptoms.
The risks associated with colored cosmetic lenses do not only concern the Halloween period. Research published in 2012 in the journal Cornea analyzed 13 cases of young patients who developed severe infectious keratitis after using colored cosmetic lenses. The data emerging from the study are worrying. The patients had an average age of 19 years, were all emmetropic (i.e. without visual defects) and used the lenses exclusively for aesthetic reasons.
In many cases, the lenses were purchased without a prescription or in unauthorized stores; some patients had even shared them with friends or relatives, and in one case a lens had been recovered from the garbage. In practice, none of them correctly followed the recommended hygiene and storage techniques for contact lenses.
The microorganisms responsible for the most common infections were Pseudomonas aeruginosa (54%), Staphylococcus aureus (25%) e Staphylococcus epidermidis (17%), with one case of viral keratitis. In 62% of patients, corneal ulcers were large, and post-treatment visual acuity was reduced to 6/24 or less.
Fortunately, all patients responded well to topical antimicrobial treatment and none required surgery. However, the study highlights how the uncontrolled availability and incorrect use of these lenses can put young people’s sight at risk at any time of the year.
Golden rules for a safe Halloween
To enjoy contact lenses safely, experts in Santiago de Compostela suggest following some practical rules:
Sources: Cornea / The Conversation
