It was completely by accident that Glenys Kelly discovered she had glaucoma.
The 72-year-old Hastings dance teacher had taken a blow to her left eye when she walked into a door frame in the dark. Sporting a bruised temple and concerned that she may have injured her eye, Mrs Kelly made an emergency visit to her optometrist, where a thorough check revealed the eye injury was minor - but she had the early stages of glaucoma.
"My eye pressures were up, compared to previous eye tests," said Mrs Kelly, who was quickly referred to an eye specialist for treatment.
Eight weeks later, she had laser surgery on her worst-affected eye. Laser peripheral iridtotomy is one of the more advanced treatments available for treating glaucoma, which has historically been the biggest preventable cause of blindness.
Mrs Kelly uses eye drops once a day to continue to treat the condition.
"I feel very lucky," she says.
"I could have gone blind and, being a very active person including cycling and teaching dance classes twice a week, it would have had a serious impact on my life.
"I have to put eye drops in every night, forever. That's a small price to pay for keeping my eyesight and being able to still teach, drive and travel."
Age and family history are the only indicators that someone could be vulnerable to glaucoma.
Mrs Kelly believes her mother had the condition.
Early detection of glaucoma is vital when it comes to preventing blindness, said Phil Donaldson, one of the team of optometrists at Visique Shattky in Hastings and Waipukurau.
"It is a slow and insidious condition, affecting the nerves between the eye and the brain and stealing away our peripheral vision.
"We are not good at noticing that loss, and that's where regular eye exams will pick it up, before vision is permanently destroyed."
New technology has made it easier to diagnose glaucoma early.
"We used to measure the pressure inside the eye, photograph the eye and look at the optic nerve. Now we scan right through that nerve and can look closely at the nerve head.
"If we see damage, we can use eye drops and/or laser surgery to lower the pressure, which treats the condition," Mr Donaldson said.
Apart from trauma, age and family history, there are no other identified causes for glaucoma.
"The only prevention is to have regular eye checks and catch it early. That way treatment is less intense and more successful.
"A full eye health check is important, takes little more than 40 minutes and will pick up glaucoma as well as any other threats to a patient's vision.
Hastings Mayor Lawrence Yule fronted up recently for his regular eye-health check, including tests for glaucoma and macular degeneration.
"The technology is fantastic," he said.
"I have no family history of glaucoma but the important thing I take away from these eye checks is how special and complex the human eye is and how much we take it for granted."
Mr Yule walked away with a clean bill of eye health.
"I would hope that during Glaucoma Awareness Month we can convince others to have the same check - and we hope they have a similar result," Mr Donaldson said.