Optometrists are calling for an end to unequal access to cataract surgery - saying too many Kiwis are being left to suffer.
A Herald investigation has detailed cases where people had to give up driving but still didn't meet the threshold for cataract surgery.
Each of the country's 20 district health boards decide their own threshold for surgery, set according to demand and capacity. Patients are given a priority score from 0 to 100, based on clinical and social need.
People who score 45 or more will get surgery at Auckland DHB, but need to score 55 or higher at neighbouring Counties Manukau. Southern DHB has the highest threshold at the country, at 61.
Andrew Sangster of the NZ Association of Optometrists (NZAO), said the numbers being denied cataract surgery was of growing concern.
"It's not a problem that's going to go away. We've got an ageing population, and we have more people living longer, which means they have more time for things like cataracts to start to bite.
"Personally, I'm not convinced the resourcing for medical eye care has grown in proportion with that need. Eye departments around the country are under-resourced, both with their budgets and workforce."
• Read the full investigation by clicking here
Sangster said in areas like those within Southern DHB boundaries, people are "well beyond their driving standard before they are being seen". That would cause huge frustration for optometrists, given the same patient would have their vision restored if they lived elsewhere.
"It is affecting people's quality of life. Their ability to live and function is quite often determined by their mobility, and doing things like the crossword or socially interact with people."
Optometrists are often the "gatekeepers" to cataract surgery, Sangster said. For some patients they'll know there's no point making a referral.
For those closer to the threshold, the optometrist will calculate a 0-100 priority score, using nationwide clinical priority assessment criteria (Cpac).
If a referral is made, the DHB ophthalmology department will calculate a Cpac score themselves. Clinical assessment of vision impairment is used, along with scoring on six quality of life questions, such as a patient's ability to interact socially, look after themselves, and any impact on leisure activities.
Those lifestyle factors were important, Sangster said.
"Sometimes you get people that don't drive, or have other circumstances that mean the cataract is not a big factor. But other people could still be working, or they may be driving or looking after grandchildren...others live rurally, and are driving on country roads with no street lighting.
"I think the Cpac system is a very important tool. It's just that we need a national threshold. And therein lies the challenge."
The Herald has profiled cases where people were declined public treatment, including 82-year-old Mavis Hall, who lives in Counties Manukau. She stopped driving as her vision worsened, despite being the main driver after her husband Douglas' knee replacement. When walking, Hall turned her head to use her good eye to spot obstacles.
"It got to the stage where I actually tripped over and had a head injury and chipped a bone in my wrist," she told the Herald. "I was doing all sorts of tripping over and knocking things, it was pretty bad."
Fortunately, Hall's optometrist mentioned her case to Dr Trevor Gray, who arranged to do the December 2017 surgery for free at The Eye Institute.
Gray has since founded his own private practice, Re:Vision, in Mount Wellington, and has partnered with Auckland Regional Charity Hospital (Arch) to carry out cataract surgeries, after realising how many people were being denied life-altering treatment by a public system that he recently left after 20 years.
Arch lets volunteer surgeons use private theatres at no cost to the qualifying patient, and Gray hopes other ophthalmologists will support the scheme, by agreeing to carry out a 20-minute cataract surgery once a fortnight or month.
Health Minister David Clark said the ministry and sector were working together to reduce wait times and improve treatment, and Budget 2018 had allocated $32 million a year to support access to a range of planned care.
"I understand how upsetting it can be when people are not able to access treatment right away, and we are working to increase delivery and reduce wait times."
DHBs were best placed to decide how much funding to put towards different specialties and surgeries, he said: "There will always be variation across the country, in line with different environments, population mix, and pressures."
Ministry of Health spokesman Sam Kunowski said comparing local thresholds in isolation could mislead.
"Quantitative information such as thresholds, intervention rates, and the number of referrals received and accepted, needs to be considered alongside qualitative information from referrers and surgical services to determine whether an appropriate level of access is being offered," said Kunowski, group manager for DHB performance and support.
• To seek possible access to Auckland Regional Charity Hospital-supported surgery (cataract or other) your GP, ophthalmologist or optometrist must submit application forms available on www.aucklandcharityhospital.org