Contact lenses warning after student nearly blinded
Medical experts have issued an alert on the improper use of contact lenses after a 14-year-old middle school student in Shenzhen, Guangdong Province, almost lost sight in an eye due to serious infection.
The female student's friend bought a pair of contact lenses online and sent them to her as gift.
She then contracted a rare infection called acanthamoeba keratitis, mainly associated with wearing contact lenses, and was almost blinded in the left eye.
Contact lenses are actually a kind of medical appliance and high awareness is needed in purchase and wearing, said Dr Yang Xiaobo from Shanghai Yida Hospital.
"Improper use of contact lenses can leave a negative impact on the eyes, such as long hours of wearing contact lenses or using lenses with an improper diopter," Yang said.
"There are no blood vessels on the surface of cornea. About 5 percent of oxygen on the surface of eyeballs is taken from the air, while contact lenses reduce the oxygen content on ocular surface," she said.
"So wearing contact lenses too long can cause dry eyes and acute keratitis. Some people wear contact lenses while sleeping or for consecutive days also can impose serious risk."
Lenses with a wrong diopter can cause dizziness and even impact vision.
Experts said people should visit a hospital to get a professional evaluation on whether they can wear contacts before using them for the first time.
"It is extremely important to check the qualification of the sellers if purchasing contact lenses online. Proper hygiene and healthy contact lens habits are important," Yang added.