By Aine Cryts
Vol. 24 No. 2 P. 22
New technology speeds up MRI exams.
Because MRI scanning requires a patient to lie still in a tube for an extended period of time, getting an MRI can be highly inconvenient for patients. This is especially true for patients who are claustrophobic, says Eyal Aharon, CEO of MedicVision Imaging Solutions. MRI can also be challenging for children, he adds. Typically, they’re sedated before they’re placed in the MRI scanner.
Lawrence Tanenbaum, MD, FACR, vice president and chief technology officer at Los Angeles–based diagnostic imaging services provider RadNet, says pediatric patients and adult patients with dementia may experience increased stress during the MRI scan. “In all cases, it’s better to get the exam done faster. In many cases, when the exams are faster, you have less problem with motion, which can be a problem with uncooperative patients,” Tanenbaum says. He previously served as associate professor of radiology and director of MRI, CT, and outpatient/advanced imaging at the Icahn School of Medicine at Mount Sinai in New York.
Improving Patient Experience
An MRI exam can take from 15 minutes to more than one hour, according to the Mayo Clinic. During that time, the patient must remain still, as movement can result in blurriness in the images that are captured. As any patient who has had an MRI knows, sitting in the machine is a noisy, uncomfortable experience. In addition, depending on the body part being imaged, the patient may need to hold their breath for up to 30 seconds at a time, according to the University of California, San Francisco Department of Radiology and Biomedical Imaging.
Being mindful of creating a good patient experience is certainly one reason to offer a faster MRI, Tanenbaum says. Tanenbaum, who has conducted research on MedicVision Imaging Solutions’ faster MRI product, notes that patients report significant discomfort and anxiety with the MRI experience. “Anytime you can make the experience more appealing by getting a patient imaged faster is a very big plus … there’s really no question that a faster examination is better. But, economically, it’s also a factor.
“Right now, we’re dealing with the pandemic shortage,” he continues. “This is a way to accomplish the same number of exams in a shorter day, so you don’t need as [many] staff, and it’s also a way of coping with a decrease in reimbursement. If you can do a [few more exams] per hour, that also helps.”
Aharon agrees. He believes that if a health care facility can cut the imaging time for an MRI to 30 minutes, for example, it is possible to have a real impact on patient care. Also, in response to reimbursement reductions and the need for health care facilities to “do more with [fewer] employees,” imaging centers and hospital executives are trying to increase their facility’s ability to image patients, he says. The question any executive or practice administrator should ask about faster MRI is simple, Aharon says: “Can I capture MRIs with all of my patients in eight hours, instead of 12 hours?”
Radiologists have plenty of questions about faster MRI, but their questions generally boil down to trying to understand whether an MRI that takes less time is a lower quality MRI, he explains. To respond to these concerns, MedicVision provides an MRI that’s captured in the typical time frame alongside one that was captured using his company’s technology. According to Aharon, there’s no difference in quality between the two sets of images. Specifically, the company conducted “extensive validation tests that we did before the product was approved by FDA, and the radiologists’ review [the tests as part of every implementation],” he says.
In addition, the company offers a trial system, which Aharon describes as a fully functional and operational iQMR system installed and implemented at the customer’s site for a time-limited trial period. The trial period typically lasts a few months, he explains. “With that, potential customers can test the system’s performance on their own scanners and verify how it integrates with their other systems [such as] PACS and RIS, prior to making a definitive purchasing decision.”
AI on the Table
There are a variety of ways to make an MRI exam faster, and many of them may sacrifice image quality, Tanenbaum says. For example, the scan can be captured at a lower spatial resolution, or fewer repetitions of the experiment can be captured. Alternatively, fewer, thicker slices could be captured, or fewer individual sequences done. The challenge lies in the fact that all four options involve trade-offs that are unacceptable to many radiologists, he says.
“What artificial intelligence brings to the table is the ability to accelerate scans without the trade-offs associated with [these attempts],” Tanenbaum says. “If we sacrifice signal in the interest of speed, artificial intelligence, deep learning reconstruction techniques have a way of restoring that trade-off, which leads to no trade-off.
“As a matter of fact, the quality generally goes up because, with all of these speed benefits and the signal benefits of a deep-learning reconstruction, we can use thinner slices [and] we can scan with higher imaging matrices,” he adds.
Describing AI as a “very powerful tool … that allows you to actually scan quickly,” Tanenbaum adds that “there’s really nothing that we do in imaging that doesn’t benefit from the ability to do deep learning reconstructions.”
Tanenbaum believes there is a need for a vendor-agnostic AI tool. “There’s an awful lot of install base out there that really does need the benefit of improved image quality, not to mention better workflow and efficiency, and those will not be addressed by the original manufacturers,” he says.
MedicVision’s iQMR product relies on AIassisted technology, which the company describes as vendor agnostic. The result, per MedicVision, is faster MRI protocols on MRI scanners with a “substantially increas[ed]” signal-to-noise ratio and image quality. The product received FDA approval in June 2018. iQMR has also received regulatory approvals in Brazil, China, Israel, Japan, and Korea.
Imaging centers and hospitals should expect to achieve 40% faster MRI scans and 35% increased productivity, with the expectation that quality will remain the same or even be better, according to MedicVision. Aharon says that more than 150 of the company’s iQMR solutions are deployed worldwide.
Randall Stenoien, MD, a diagnostic radiologist and CEO of Houston Medical Imaging, started looking into iQMR because MRIs are “pretty time-sensitive procedures [where patients may need] a little extra time,” he says.
“We needed to shorten imaging times without losing image quality,” Stenoien says. His practice uses iQMR. “[Before using the product], we also found that we were limited in the number of [imaging slots that we] could actually create.
“We were able to shorten up those examinations,” he says. “[For] some of those examinations, we were able to shorten into a 15-minute slot.” Stenoien notes that, although not all exams can be captured in this time increment, the time to capture images has decreased across the board.
“It opens up opportunities for accommodating additional patients,” he says. “We found that … we could accommodate between four and six additional exams, which is an increase in productivity of about 30% to 35%.”
Stenoien explains that, in order to change the protocol incorporating the use of iQMR, a diagnostic radiologist at Houston Medical Imaging had to sign off on the comparable quality of images captured in the standard protocol compared with the new protocol. There has also been no change in radiologists’ workflow, Stenoien says. “We had a pretty tight collaboration between our technologists and MedicVision, in terms of coordinating how the sites were set up.” Once the iQMR protocol has been adopted, the learning curve for technologists isn’t onerous, either, he says. He adds that faster MRIs also help with patient flow, particularly when patients show up late for their scans, which can throw off the schedule.
Another way faster MRIs help with scheduling is if a patient needs to be rescanned because their breathing was off or they were moving during the exam, he explains.
Stenoien says iQMR’s more efficient patient flow has reduced technologists’ stress levels; they’re not spending the day trying to catch up, he says.
At RSNA 2022, Subtle Medical announced a new product, SubtleSYNTH, which is pending FDA approval. It will be commercially available in the coming months. SubtleSYNTH uses deep learning to synthesize short tau inversion recovery like contrast from already acquired T1 and T2 contrasts, according to an announcement, which notes that the first commercial release will support spine imaging, with other anatomies to follow.
The company’s other MRI product, SubtleMR, uses denoising and resolution management to improve MR image quality on standard and accelerated protocols. Subtle Medical says many of its clients use the platform for 60% faster protocols. The product has received FDA clearance, as well as clearance in major international markets in the European Union and Canada, per the company.
According to Greg Zaharchuk, MD,PhD, cofounder of Subtle Medical, there are two differentiators for Subtle Medical’s fast MRI products. One is that its software solutions are vendor neutral, unlike original equipment manufacturer solutions that only work on specific brands of scanners, typically newer models. Subtle Medical’s products can be used on magnets from any company and on both newer and older scanner models. Zaharchuk, who is also a neuroradiologist and professor at Stanford University, says, “This is especially beneficial for large institutions [that] want the time-savings benefit across their entire fleet of scanners.”
The second differentiator, Zaharchuk says, is that SubtleMR keeps on learning. As an AI/deep learning tool, “it has the ability to continue improving as the training data continues to evolve vs other [platforms] that are traditional filtering or reconstruction products.” Zaharchuk says both products also benefit from routine software upgrades that occur on-site and in the cloud.
“Our fast MRI software solutions increase workflow efficiency, [which] allows centers to scan more patients per day, reduce wait times, and increase scanner capacity on existing scanners versus purchasing new magnets,” Zaharchuk says.
According to Zaharchuk, Subtle Medical’s products also improve image quality and patient care. “Our fast MRI software solutions help radiologists maintain diagnostic confidence, even on suboptimal and accelerated scans, enabling patients to get in and out of the scanner in a fraction of the time,” he says.— Aine Cryts is a health care writer based in the Boston area.