The news: Please, for the love of God and all that is holy, do not leave your contacts in. The very unfortunate 23-year-old Taiwanese undergraduate student Lian Kao learned this terrible lesson the hard way: She neglected to remove her contact lenses for a shockingly long six months, apparently wearing them in places like the swimming pool and bed.
The result was pretty horrible, even as far as medical mishaps go. The surface of Kao's eyes proved to be wonderful breeding grounds for single-celled amoebas of the Acanthamoeba variety. Not only did they flourish and multiply, they ate her corneas.
"Contact lens wearers are a high-risk group that can easily be exposed to eye diseases," ophthalmologist Wu Jian-Liang of Taipei's Wan Fang Hospital told the Daily Mail. "A shortage of oxygen can destroy the surface of the epithelial tissue, creating tiny wounds into which the bacteria can easily infect, spreading to the rest of the eye and providing a perfect breeding ground. The girl should have thrown the contact lenses away after a month, but instead, she overused them and has now permanently damaged her corneas."
How it happened: Acanthamoeba feasts on bacteria. Because Kao did not disinfect her contact lenses at any point, there was a lot of the latter, and the critters actually burrowed into the ocular tissue as the colonies on both eyes grew. The resulting condition, called Acanthamoeba keratitis, can cause pain, eye redness and blurred vision — but it is usually not painful enough for sufferers to decide to seek medical attention until it is too late.
By the time people suffering from Acanthamoeba keratitis notice something is seriously wrong, it is usually very difficult to get rid of the infection. Prescription drugs are most effective in the early stages. In serious cases patients require a corneal transplant, a procedure that has a high failure rate.
So now you know: Take out and clean your contacts on a regular basis, or you could end up with a serious and potentially irreversible condition.