A clinical professor at the School of Optometry and Vision Science and a lead clinical scientist at the Centre for Ocular Research and Education (CORE), at the University of Waterloo, is flipping the conversation on myopia detection and diagnosis.
Dr Deborah Jones argues that axial measurement should be the starting point for optometrists, alongside refraction, even if you don’t have specialist equipment in practice.
Dr Jones was in Melbourne to speak and present a poster at the 4th World Congress of Optometry in September. In an exclusive interview with mivision, she said axial length is often described as the “final piece in the puzzle” but, in fact, it could be considered the first.
“It’s the axial length that tells the story, not the refractive error. Because… there’s good evidence that axial length changes before the myopia kicks in,” Dr Jones said. “You can actually predict, by watching axial length change, when that child is going to become myopic or whether they are going to become myopic. And you can start looking at lifestyle changes early on. I think we’re shifting, certainly I’m shifting my focus clinically to, ‘Every child is a potential myope’, not, ‘Let’s wait until they’re myopic’.”
MAKE IT ROUTINE
Dr Jones, who specialised in paediatric optometry, said axial length should be a routine measurement alongside refraction for all children, and optometrists should now be adding equipment for axial length management to their “shopping list” for the near future.
Noting the multifunctional equipment now available to eye care professionals she said, “There’s a fundus camera, and an optical coherence tomographer that measure axial length… a handheld axial length option is going to be made available within the next couple of years, which I think is going to hit the market at quite a competitive price.”
Even if you don’t have the equipment now, you should still be considering myopia control options for all of your suitable patients.
“You don’t need to measure axial length to manage myopia or to do myopia control. So don’t be put off thinking, ‘Oh, I don’t have the equipment, so I can’t do it’. You can do it very, very well. Axial length measurement just provides additional invaluable information.
“There are some programs online where you can calculate axial length using keratometry a nd refractive error. They’re not as accurate, but maybe better than nothing.”
Alternatively, she said, “You could get the measurement done elsewhere at another practice or by an ophthalmologist.
“So, the message really is, you should be doing it if you can. Ideally you do, but if you can’t and you haven’t got the equipment, consider sending them off for that particular measurement. Whatever the decision regarding the axial length measurement – still manage the myopia!”
LOW AWARENESS, RISING PREVALENCE
As in Australia, Dr Jones said there is low awareness of myopia in the Canadian community. She said one study, in 2016–17, found that about 30% of children aged eight to 16 years old had myopia, and about 30% of those had no idea, so didn’t have vision correction.
While she doesn’t believe the myopia prevalence in Canada will “get to 90% of teenagers like Asian countries”, there’s a large proportion and prevalence is increasing.
“During COVID in particular, with everything being on screens, there was no distance world for children to be looking at. So, we’ve seen a huge increase in children that are coming to us being more myopic than we would expect.
“They come in (to the practice) at age eight or nine, and they’re already a minus two myope, and it’s like, ‘How did you not know?’”
GET PARENTS ON BOARD
Dr Jones stressed the importance of patient and parent/carer education to ensure all parties are on board with treatment plans early, recommending apps and literature that demonstrate myopia progression and its consequences over time.
“Get them to appreciate why you want to slow it (myopia) down, why it’s important and what the potential is if you don’t… Show them and say, ‘These are the risks. Let’s preserve your child’s ocular health from the get-go and make life easier for them with a lower prescription, and better options for laser vision correction (in the future)’,” she said.
