When Dave Evans underwent surgery to remove a pituitary gland tumour last October, his surgical team worked within an area roughly the size of a thumbnail.ย
In that tiny space near the base of Evansโs brain, neurosurgeon Dr. Neil Duggal and other clinicians at the London Health Sciences Centre (LHSC) in Ontario were aiming to fully take out a growth that was causing the 65-year-old Owen Sound, Ont., resident extreme fatigue, headaches and vision loss. It wasnโt an easy task: The pituitary gland, which releases hormones that help regulate a range of essential bodily functions, is flanked by crucial arteries and nerves leading to the eyes and brain.
โWe want to be very careful as we get out to the sides because if we injure those arteries, that can lead to catastrophic hemorrhage and stroke or death,โ Duggal told CBC News.
Surgical teams typically have to wait for a followup MRI to reveal precisely how much of the tumour they were able to safely remove, and how much they left behind.
But in the case of Evansโs surgery, the team at LHSC paused mid-procedure and used the hospitalโs new mobile magnetic resonance imaging (MRI) to check their progress. Seeing some residual tumour on the scan, Duggal went back in through Evansโs nose to remove close to 99 per cent of the benign, life-altering growth.
Mobile brain scanners sound like something out of science fiction, but theyโve been around for more than a decade. A rising number of Canadian health-care facilities are now using these moveable machines for a wider range of medical procedures, from removing pituitary tumours in hospitals to diagnosing strokes and brain hemorrhages out in the community.
Duggal called the approach a โgame changer,โ and has since used the hospitalโs mobile MRI during five more pituitary tumour surgeries in hopes of reducing the chance of more people needing followup procedures.
โI think the value of that is for the patient is priceless, right?โ
Rising number of mobile scanners in Canada
MRI machines use powerful magnets and radio waves to generate images of the bodyโs organs, bones and soft tissues, while computed tomography (CT) scanners rely on X-rays โ and they both tend to be large, standalone devices stationed within hospitals.
There are now mobile or portable versions of both types of device, which rely on lower-strength magnets or radiation to operate remotely, while scan images are produced through artificial intelligence.
Data compiled by the Canadian Agency for Drugs and Technologies in Health shows that by 2023, there were at least 16 of these mobile devices being used across the country, up from less than 10 machines a few years earlier.
While ongoing research is needed to confirm how much of a difference mobile scans really make for patient care, physicians say thereโs immense promise for improving surgical outcomes and reaching patients in rural and remote regions.
โIt’s an exciting technology. It clearly has demonstrated a clinically relevant context of use,โ said Yale University neuroscientist Dr. Kevin Sheth, who studies new medical technology. โWe’re at the very early stages of needing a lot more research to really understand, in a meaningful way, how it can help patients.โ
Growing use of these tools in Canada and beyond is driven by technological advancements and lower costs, researchers say.
โThe technology is incredible. It continues to get better and better,โ said Sheth, whose own research shows portable MRIs are nearly as effective as standard ones in detecting strokes.
Mobile MRIs and CT scanners also cost less upfront, at hundreds of thousands compared to north of a million dollars, experts told CBC News.
โLower cost and smaller machines could be purchased outright by some facilities that might not either wise be able to purchase them. That’s one option,โ said Francis Shen, a law professor at the University of Minnesota, who is among the researchers studying the impact of mobile scanners.ย
Another option, he said, is for multiple facilities to share mobile devices.
โThe idea is to sort of flip the paradigm. Instead of the patient coming to the scanner, the scanner is coming to the patient,โ said Sheth.
Edmonton’s mobile stroke unit operates 7 days a week
In Alberta, Canadaโs only mobile stroke unit is doing exactly that, by using a CT scanner inside an ambulance to diagnose strokes on the road.ย
Dr. Ashfaq Shuaib, a neurology professor at the University of Alberta, helped launch the program back in 2015 and said the unit now operates seven days a week, with a radius of 250 kilometres around its home base in Edmonton.
The team drives to areas without local CT scanners, meets regular ambulances carrying suspected stroke patients midway, and brings them on board for a roadside scan. That gives paramedics near-instant confirmation that someone is having a stroke.
Stroke can be caused by a blocked vessel, which requires clot-busting medication as quickly as possible. Shuaib said bringing scans right to patients helps save more lives.ย
โIf you can get the clot-busting drug in the patient within one hour, two-thirds of them make a full recovery. If you treat them within four hours, that number goes down to less than a third,โ he said. โIt’s extremely time-sensitive.”
The mobile scans can also show cases where stroke is caused by a burst vessel instead of a blocked one.ย
“You need to scan a patient before giving them a clot-busting drug because you need to be absolutely certain it’s not a hemorrhage,โ said Shuaib. โUnless you do a scan, there’s no way to make that distinction.โ
Small studies from mobile stroke units being used in other countries back up those benefits. In one randomized controlled trial in Germany, treatment was started within an average of under 40 minutes for patients seen by a mobile stroke unit, compared to more than 70 minutes for a control group who received traditional care, with no increased risk of brain hemorrhage among patients seen by the mobile team.
‘Exciting’ potential for this emerging technology
Mobile teams are a win-win, helping improve patient outcomes without tying up hospital resources, Shuaib said. Yet the Edmonton stroke unit remains the only one of its kind in Canada, more than a decade after its launch.
Multiple researchers said thereโs still major room for growth in the use of these devices, both in the community and in hospital settings, but also cautioned that itโs still early days โ and the machines arenโt foolproof.
Mobile scanners require fast wireless internet, which can be tricky in rural areas, and provide lower-quality images than those produced by traditional machines.ย
โIt’s maybe akin to thinking about the difference between watching a movie on a phone and watching a movie at a movie theatre,โ said Shen. โYou don’t always need to see a movie at the theatre. The phone can be useful for a lot of things. But there’s a real difference between the two.โ
He stressed the need for ongoing improvements in the technology itself, and having trained clinicians on hand to interpret the results. Still, he said the potential is enormous for improving accessibility to much-needed MRIs and CT scans.ย
โI do think we’ll be in a place where looking beneath the skull will lead to better health outcomes, and that’s really, really exciting.โ
As for novel uses of this technology โ such as the mid-surgery MRI conducted last year in London, Ont. โ Sheth said those possibilities still need to be replicated in broader research.ย
Evans, who only learned about the use of a mobile MRI after his procedure, said heโs just happy that the team was able to remove so much of the tumour that was draining his quality of life.
Since the surgery and subsequent hormone replacement therapy treatment, he has regained his vision and energy, and said he feels โat least 10 years younger.โ
โThe fact that they got most of it โฆ the chances that it would come back, they put at about two or three per cent,โ Evans said.
โSo itโs such a good long-term prognosis.โ
