It's now harder to get life-changing cataract surgery in large swathes of the country - leaving desperate patients unable to drive or read.
A Weekend Herald survey of all 20 DHBs shows surgery thresholds in a number of regions have toughened significantly.
DHBs give referred patients a score from 0 to 100 (lowest to highest priority), according to clinical and social need, and set a threshold for surgery.
In Auckland, for example, anyone with a score of 45 or higher gets surgery within four months. But in the Waikato, patients have to score 60 or more.
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Waikato DHB is one of seven to have toughened its threshold since March last year - moving from 53. Others include the Wellington and Wairarapa DHBs, Lakes, Whanganui and (slightly) Bay of Plenty.
David Willemsen was one of those affected by the high bar for surgery. A cataract on the 56-year-old's right eye worsened considerably over the past year, to the point where driving became too hard, as vision clouded over.
The Te Awamutu resident loves to hunt with his teenage son, but that and other everyday activities became impossible.
"Looking through my right eye through the scope, I could see about four different cross-hairs.
"My sight seemed to be going really fast. I was just losing it. It was pretty scary."
Despite that, he didn't meet the threshold set by Waikato DHB for surgery. However, his optometrist persisted, and after a reassessment he scraped over the threshold, and had surgery on Monday. That took just 15 minutes, and by the next morning his world had opened back up.
"I went out this morning, and I could see all the detail in the grass. How amazing is that - my vision is so much better. It is crazy ... I'm actually thinking of going for a shoot this weekend.
"I feel privileged that I got it done. That's what I feel bad about now - is other people aren't getting in. I hope they can try and get more people through."
Waikato increased its threshold to 63 in March, the highest in the country and in response to Covid's impact on electives. This week it dropped to 60, and a DHB spokesperson said it would be reviewed again within two months, with a view to reducing it further.
"The DHB has increased capacity through the introduction of weekend theatre allocations and increased outsourcing for certain procedures ... the backlog created during the lockdown is now almost entirely cleared," the spokesperson said.
"Waikato DHB is developing a programme of work to reduce wait times, improve access, be responsive to the needs of Māori and address the inequity of access to cataract surgery."
The ophthalmologist who removed Willemsen's cataract, Dr James McKelvie, last week published in the NZ Medical Journal an analysis of all 44,000 patients referred for cataract surgery, nationwide and from 2014 until March 2019.
More than one-quarter of patients who were declined for surgery - which is quick and relatively low cost - did not meet the visual acuity requirement for driving a private vehicle in NZ.
The number of operations and percentages of referrals declined varied greatly by DHB, the research found. Lakes DHB approved just over half of referrals, for example, and West Coast DHB approved 93 per cent.
The Weekend Herald's survey of DHB thresholds shows some health boards have raised thresholds since that research period.
Thresholds can move, based on capacity and demand; Bay of Plenty DHB had a threshold of 59 last year, this later went up to 61, and dropped to 60 in August, due to a decrease in referrals.
Capital & Coast and Hutt Valley DHBs, covering the wider Wellington region, increased the threshold from 47 to 52 in April, "to better ensure we are able to treat patients in a timely manner within our existing resources", director of provider services, Joy Farley, said.
"Our Cpac scores are consistent with those of other DHBs around the country, and in line with both Ministry of Health guidelines and safe clinical practice."
Whanganui's threshold shot up from 53 to 60 in August last year, after staffing reduced to one surgeon. The DHB says it hopes to hire another surgeon imminently.
The Royal Australian and NZ College of Ophthalmologists (Ranzco) has taken the rare step of calling on the Health Minister to set a nationwide threshold for acceptance for surgery.
Any response to Ranzco's call for a nationwide surgery threshold will be for incoming Health Minister Andrew Little, who only officially took over yesterday.
However, last week his predecessor Chris Hipkins noted Budget 2020 allocated more than $282 million to catch up on elective surgery disrupted by Covid, including cataract surgeries, and during the election campaign Labour pledged another $200m to cut waiting lists.
The ministry has previously said comparing local thresholds in isolation could mislead, with other information like how many surgeries are done and the number of referrals accepted also important to consider.
Demand for eye services has boomed as Kiwis age and sicken with conditions including diabetes which, if not well controlled, can destroy eyesight. New treatments such as Avastin injections for age-related wet macular degeneration have saved the sight of tens of thousands, but can be needed monthly and have put huge strain on resources.