It can lead to vision loss, visual impairment and even blindness.

BBC: Massive rise in Asian eye damage

When the suits are heard, a parade of experts can be expected to testify that an improper lens can painfully scar the cornea and potentially lead to vision problems and even partial blindness.

FORBES: An Eye For An Eye

Their mechanism may even work on other diseases, such as macular degeneration, a leading cause of blindness, and even eye damage from diabetes, some researchers believe.

FORBES: Targeting Tumors

Too much mercury in one's diet from any source can cause loss of coordination, blindness or even death.

CNN: Beware of shark meat, FDA warns

Possible features include a binocular heads up display, corrective lenses, a hearing aid app, color blindness correction, even an app to aid those with macular eye disease.

FORBES: Google Glass Is Here!

"Blindness" was even selected as Cannes' opening film.

CNN: Cannes exposure is no guarantee of success

It is a very potent antioxidant, and numerous research studies have found an association between greater intake of beta carotene-containing fruits and vegetables and a reduced risk of disease including heart disease, diabetes, osteoporosis, age-related macular degeneration (the leading cause of blindness in older Americans) and even certain types of cancers.

CNN: Should I take beta carotene as a supplement?

Part of the issue is that the benefit of taking insulin is so big--preventing blindness and organ damage--that even a small long-term cancer risk might be acceptable.

FORBES: Magazine Article