• e-mail

One in five Americans face preventable blindness and don't know it, experts warn. 

Glaucoma, the second leading cause of blindness according to the World Health Organization, will affect around 61 millions Americans in their lifetime.

That figure is set to double in the next 30 years, costing the US $100 billion in direct and indirect health costs. 

However, the tell-tale symptoms are not as simple as losing the ability to read a registration plate - and can come on months before you lose your sight.

Though there is no cure, early detection can catch it in time to administer eye drops or laser eye surgery that delay vision loss. 

And yet, figures show fewer than a 10th of Americans get their eyes checked. 

Around 61 million Americans are at risk of developing glaucoma - a leading cause of blindness that carries barely no symptoms until it is too late to take preventative action

The bombshell data, which emerged in a CDC-sponsored report late last year, sent shockwaves through the medical industry. 

'I was amazed by the report,' admits board certified ophthalmologist Elizabeth Yeu.

'Sixty-one millions Americans - that is a lot.' 

She explained: 'We just don't realize how delicate eyesight is. 

'You don't have a sign like redness or pain. Eye disease can asymptomatic.

'The only way to be sure is to get an eye exam.'

There is no known cause for glaucoma; rising rates are not driven by increased screen use, which causes chronic dry eye. 

Symptoms may not appear until months before patients suffer crippling vision loss. In many cases, it starts with blurring of peripheral vision. 

Glaucoma is a condition which can peripheral sight, usually due to build up of pressure damaging the optic nerve, the vital link between the eye and brain.

It often affects both eyes, usually to varying degrees. One eye may develop glaucoma quicker than the other.

The eyeball contains a fluid called aqueous humor which is constantly produced by the eye, with any excess drained though tubes.

The condition develops when the fluid cannot drain properly and pressure builds up, known as the intraocular pressure. 

Eye drops can't repair the damage but they can stop it from getting worse.

This can damage the optic nerve (which connects the eye to the brain) and the nerve fibers from the retina (the light-sensitive nerve tissue that lines the back of the eye). 

Glaucoma can be treated with eye drops, laser treatment or surgery. But early diagnosis is important because any damage to the eyes cannot be reversed. 

Treatment aims to control the condition and minimize future damage.

If left untreated, glaucoma can cause visual impairment. But if it's diagnosed and treated early enough, further damage to vision can be prevented. 

For years, experts have been warning health officials that glaucoma is an imminent threat to public health.

But even leading ophthalmologists were stunned by last year's report, by the National Academies of Sciences, Engineering, and Medicine (NASEM), presenting unprecedented data.

It was the first paper to table the figure that 61 million Americans are at risk of glaucoma. 

The authors wrote: 'Avoidable vision impairment occurs too frequently in the United States and is the logical result of a series of outdated assumptions, missed opportunities, and manifold shortfalls in public health policy and health care delivery.' 

In response, Allergan - a pharmaceutical giant with 70 years' experience in eye care - has launched a multimillion-dollar campaign to crush preventable blindness by 2030.

See America - involving charities, yet-to-be-revealed celebrity endorsers, and some of America's leading vision experts - is slated to offer free eye screenings and vision education nationwide. 

Notably, the company will profit considerably from more prevalent eye care.

Dr Yeu insists the campaign is a necessary stepping stone to target a disease that has robbed so many of her patients of their vision. 

'Be proactive. Get that annual comprehensive eye exam because the earlier the treatment, the better the chances are that you’re going to be able to save your sight.'