Sight for sore eyes
Baby boomers are hitting the age where cataracts could impair their eyesight. Mark Broatch got an early taste
The knife sliced deeply into my right eyeball, through the cornea, heading for the lens behind my pupil and iris. But I felt nothing. I could see a kaleidoscope of lights and colours, the shadows and shapes of instruments, detect some probing and tugging, as well as the cool antiseptic washes, and hear the reassuring words of the surgeon checking every detail and guiding me through the operation. But pain? Not a jot.
This is because my eye was numb, anaesthetised in place, and unable to blink, thanks to metal clips not unlike the device Alex is forced to wear in A Clockwork Orange. I was flat on my back in an operating theatre in Auckland’s Greenlane Clinical Centre. A plastic drape was over my face, a small flap providing access to the job at hand. Earlier, a nurse had checked the blood pressure and paperwork of the dozen or so people awaiting treatment, administered a series of drops over about an hour and marked the correct eye with a blue Sharpie arrow just above the brow.
The surgeon’s target was a cataract. This is when the proteins of the cells in your eye lens clump together and cloud your vision. It’s most commonly the natural result of age, your eyes being no different from any other part of your body in stiffening, thinning and wearing out. Usually, cataracts occur in both eyes, progressing at about the same rate, and surgery to replace the hazy section of each with an artificial lens is currently the only option. Untreated, they can lead to total blindness.
Yet I am decades too young to have a serious cataract. My surgeon, James McKelvie, a cornea and anterior segment specialist who’s done northwards of 1500 cataract operations, estimated later that the average age of his patients and those in other studies was about 72. The solid fellow ahead of me is about 10 years older than I am; the woman who will follow me is a vigorous 85-year-old, a teacher until just a few years ago.
The waiting room is a cross-section of the retired: European, Pasifika, Indian, waiting patiently with their husbands, daughters, grandkids; some are in
The proteins of the cells in your eye lens clump together and cloud your vision.
wheelchairs, a few sport ill-advised tattoos from half a century ago on looser, sun-grilled skin. We’re waiting to have what is by far New Zealand’s most-frequently performed surgical procedure, one that, even more than knee ops and hip replacements, can completely transform our later lives. Yet it’s one that many people know little about.
Here’s what happens. (The squeamish might want to skip to the next paragraph.) Generally, three cuts are made to the eye, two of about 1mm and the other about twice as large, all removal of the cataract being done through that 2mm or so gap. A tiny hole is made in the capsule the lens sits in and in goes an ultrasound probe that emulsifies the section of clumping, then sucks it out. A miniature vacuum cleaner gets every last clouded cell. Extreme care is taken not to touch the inside of the cornea or the back of the capsule, either of which can spell disaster for your vision. One of the final steps is the surgeon injecting the intraocular lens, which has been precisely manufactured to optimise your sight in that eye. The new lens unfolds itself a little like a beach tent. The cuts in your eye are then sealed using a salt solution. After about 20 minutes, you’re done – your eye gets a dousing of antibiotic, a packing of gauze and an attractive clear-plastic patch.
“That wasn’t so bad, was it?” McKelvie asked, knowing I’d been a touch apprehensive beforehand. Let’s not go too far, I said.
After another hour, you are free to leave, although you can’t drive. About eight hours later, you can remove the patch. The summer night was still light. At first, I panicked – my eyes were seriously out of alignment. My right was focusing a couple of metres from the left. Then I realised this must be the anaesthetic still working. The colour of the light seemed brighter, whiter, like that from an LED bulb rather than an incandescent. But the trees, houses and power lines were sharp, not fuzzy blurs just able to be made out.
The next day, I went back to check the healing. Apart from being a bit sore and extremely bloodshot, my eye felt fine, and McKelvie asked me to read the chart. I breezed through the bigger letters and got only two wrong on the bottom line. I had gained eight lines. In 24 hours, I had gone from Blind Foundation territory in my right eye – its threshold is 6/24, when I was an even worse 6/30 – to just short of 6/6 (20/20) perfect vision, a not-untypical result of a cataract operation. I thought, I must write about this.
MEDICAL MIRACLE
Cataract surgery is done perhaps 30,000 times a year in this country, yet all many people know is that it’s a disease of the eye. Some confuse it with laser eye surgery, or aren’t certain if it is related to glaucoma or macular degeneration (it’s not). Friends even wondered if I’d have to wear a piratelike eye patch for weeks (you don’t).
Twenty years ago, cataract surgery involved several days in hospital, more complications and less certain results. So, modern surgery, for
“For every dollar spent on cataract surgery, the return in terms of quality of life is unsurpassed in elective surgery.”
elderly people in particular, is a medical miracle. Cataract sufferers often say they stop going out at night, or socially at all, or can’t recognise people. One woman pre-surgery said it “narrows your whole life down to a smaller existence”.
Cataracts are also hard to beat in terms of toughly contested healthcare dollars, as judged by the evidence-based QALYs – quality-adjusted life-years. “For every dollar spent on cataract surgery, the return in terms of quality of life is totally unsurpassed in elective surgery,” says McKelvie. Hips and knees “pale in comparison”, he says. “Nothing comes close.”
The rule of thumb is that by the age of 70, most people will have some visual impairment as a result of cataracts. Some degree of cataract is almost ubiquitous after about 50. Yet often the first sign for many older
The rule of thumb is that by the age of 70, most people will have some visual impairment as a result of cataracts.
people is when they fail their driving test. (The cut-off for driving is 6/12.)
Eighteen months ago, all I knew was that the vision in my right eye had become fuzzy, like watching an online video that’s been downgraded in quality because you don’t have enough bandwidth. My optician couldn’t correct that eye no matter what she tried, and sent me off to a specialist. A couple of tests later, including an excruciating one that checks your field of vision using pinpricks of light, and no one appeared any the wiser. It was only on the last, a tomography test, I think, that they confirmed a shadow. They may have detected it earlier, but nobody told me. My wallet was $800 lighter, but I had a diagnosis. I did nothing for a year because I didn’t have $5000 for private surgery. The type of cataract I had (posterior subcapsular) can progress quickly, says McKelvie, and it did. The haze became a fog, my eyesight worsening by 20% in a year.
Reading and writing are relatively important in my job. As is being able to look after a one-year-old. I had stopped driving at night because headlights had become like the lens flares in bad movies, I had to wear sunglasses during the day to combat the painful glare, and my sense of perspective was deteriorating – making crossing roads with a baby buggy more hazardous. So eventually I went back to my optometrist.
The questions on the assessment form reflect the average age of sufferers, being along the lines of: How difficult do you find it to get around? And it’s your total vision that counts – if your other eye is good, your score goes down. And people don’t notice for a long time. “Part of the problem is that the decline in vision and quality of life is so gradual and so subtle that you don’t know it’s happening,” says McKelvie. People regularly come in and say they can drive fine, will swear they can see everything, he says. And then they have the surgery.
MEETING OUR NEEDS
So, why did I have cataracts? Other than age, factors are
diabetes, smoking, trauma to the eye – and bad luck. Although bad luck may simply mean that science doesn’t know yet – some rogue genetic or environmental factor.
Some good luck arrived in the form of a clinical trial that McKelvie is part of that’s assessing the incisions made during surgery, which may have helped me squeak into being eligible. The cuts can affect astigmatism – when the shape of your cornea, or sometimes the lens, is imperfect and light isn’t focused sharply enough on your retina.
One of the goals of the study, being done under the auspices of Professor Charles McGhee at the University of Auckland, is to be able to reliably reduce the post-op astigmatism to as close to zero as possible. “I believe this may be possible by better understanding how to precisely predict the effect of the incisions used and then customise the exact size and placement of each incision to every patient with a high degree of accuracy,” says McKelvie. My astigmatism was slightly reduced, though at this point it was a result of good luck rather than the intended good management.
Are we doing enough cataract surgeries to meet our needs? Last year, 16,420 publicly funded cataract operations were performed nationally, according to the Ministry of Health. A small number would have been done through private facilities, and DHBs received about $44.35 million for cataract surgery that year. The total number of cataract operations is probably closer to double that when you add in private surgeries (those numbers being closely guarded), and one estimate had the national annual cataract spend at $120 million.
The number has been increasing. In 2005, Helen Clark announced a plan to boost the budget to fund about 8000 public operations a year and reach 12,000 by 2007-08. That number was hit, 12,772 operations being done in 2008, and the 16,420 publicly funded cataract procedures provided nationally last year was an increase of 29% in the eight years since, says the ministry.
However, we are well behind the OECD average of about 1000 per 100,000 people a year. Australia reported 230,000 operations in 2014, the population equivalent of about 80,000 operations here.
The number of cataract operations is likely to increase rapidly, McKelvie says, given the ageing population, medicine’s ability to intervene earlier, and a more demanding generation coming. “The baby boomers are now heading into cataract territory.” The generation preceding the boomers hoped that doctors would intervene when required. The boomers will “demand remedies to improve their quality of life, and they’re willing to pay for it”.
Knowing how important vision is to quality of life, why would you wait, he says.
The 16,420 publicly funded cataract procedures performed nationally last year was an increase of 29% in eight years.
Interestingly, our relatively low number of operations may be one reason we have some of the best eye surgeons anywhere, reckons McKelvie, who next year will be seeking a permanent consultancy position.
One peer-reviewed study found we have fewer than expected complications. A reason may be that, apart from careful training, surgeons here have to tackle more mature, more complex cataracts more often than in other countries, and some eye surgeons moving here from elsewhere need time to adjust to a more challenging and complex caseload, he says.
EXCELLENT OUTCOMES
More operations will need better, faster assessment. The country’s cataract assessment system might be improving, again thanks to McKelvie. Currently, an optician or GP will detect a cataract and fill out a form manually. The form will be assessed, and an appointment booked with a specialist to see if the sufferer is eligible for treatment in the public system. Given a lack of knowledge among sufferers, the barriers to getting a referral and human inertia, people can wait several years with a decreased quality of life.
In 2015, McKelvie won the new ideas category of the Clinicians’ Challenge, a Ministry of Health information-technology initiative, for his web-based software that aims to smooth electronic referral, risk assessment and real-time audit of cataract surgery.
The software, called CatTrax, is about to enter a three-month pilot in Waikato. It captures all data digitally and in real time to reduce major surgical complications and aid better patient outcomes by making use of technologies including artificial intelligence and machine learning. The next stage will allow surgeons to fine-tune all aspects to maximise outcomes for all patients on a case-by-case basis.
Although cataract surgery typically produces excellent results for patients, there are still opportunities for improvement, McKelvie says.
“The public system is not optimised to accurately assess risk before surgery and analyse patient outcomes following surgery, which typically involves large amounts of complex data. Even if detailed preoperative and outcome data is routinely collected, a comprehensive analysis to provide actionable clinical insights requires knowledge of advanced statistics and can be very time-consuming and expensive to do. My suspicion is that there may be a large burden of cataract in the community that is currently unrecognised.”
My small burden was among that number. If I have one complaint, it’s that I still need reading glasses, the artificial lens I have being optimised for long distance, and that I’ll have to update my regular glasses for the change in vision. But I can now drive in sunglasses. Though now that my “good” eye is the one with the new lens, I can see that the previously good one, the left, is getting mistier. It may be some time before my score gets high enough again to get near the knife. I can wait.
“Part of the problem is that the decline in vision and quality of life is so gradual and so subtle that you don’t know it’s happening.”