Australian researchers have developed a new eye test that could detect glaucoma, which is a leading cause of blindness, four years earlier than current techniques.

Glaucoma is a group of eye diseases which damage the optic nerve, causing vision loss. The disease is hard to catch though, as peripheral vision - which isn't usually tested by doctors - is the first to go, and there's no pain to alert the patient that something could be wrong.

But now researchers from the University of New South Wales (UNSW) in Australia, have created a new diagnostic test, where patients are asked to look at small dots of light at specific size and intensity. If the patients can't see them, it shows blind spots on the eye and loss of peripheral vision – a precursor to glaucoma.

"Glaucoma is one of the leading causes of irreversible blindness in the world, and in the early stages patients usually have no symptoms and are not aware they are developing permanent vision loss," said one of the researchers, Michael Kalloniatis.

"The cause of the disease is unknown and there is no cure, but its progression can be slowed with eye drops or surgery to lower pressure in the eye. So, early detection and early treatment is vital for prolonging sight."

Right now, doctors rely on tests such as eye pressure and visual field testing to make sure their patients' eye sight is working okay. And although this can reveal glaucoma in its later stages, it's often too late to prevent it from doing damage.

The UNSW researchers have just published a study that assessed 13 patients with early glaucoma or optic nerve damage, and 42 people without eye disease, using their tests as well as currently available methods.

The new test detected greater vision loss in all patients compared to current techniques.

"The current method of visual field testing, which uses just one dot size, is good but not ideal. Our test appears to be much more sensitive at detecting disease in an early stage. On average, we expect we will be able to detect glaucoma four years earlier than at present," said Kalloniatis.

The team is currently using the same eye test to assess 30 more patients, and hope to conduct a much larger clinical trial to determine exact effectiveness of the new test in the coming months.  

"We hope our new approach will eventually be introduced around the world, and treatment can begin earlier to slow down vision loss in glaucoma," he said.

The new diagnostic technique has already been patented in the US and European Union.

The study was published in Ophthalmic and Physiological Optics earlier this year.

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