MRI — What Geriatrics Professionals Should Know
Medical imaging plays a crucial role in diagnosing and treating older adults. Many providers don’t fully understand key safety considerations for these exams and procedures.
Medical imaging can be a lifesaving tool when it comes to diagnosing diseases and medical conditions. But as with any procedure, there can be some risk involved. This is especially true for older adults who may have special considerations that must be taken into account prior to undergoing imaging procedures, such as implanted pacemakers, aneurysm clips, or even difficulties remaining still during procedures.
Older adults who have implantable devices are at the highest risk when it comes to MRI scans. “The M stands for magnetic and, considering implantable devices are metals with hardware, software, and electronic components, they can interact dangerously with a large magnet,” explains Anne B. Curtis, MD, FHRS, FACC, FAHA, a professor of medicine and chief of the division of cardiology at the University of South Florida in Tampa. Because some implantable device components may be sensitive to an MRI’s magnetic field, it can put the patient in danger. For example, Curtis explains, a pacemaker may interpret the electrical noise coming from the MRI machine as the heart beating. Because a pacemaker is a device that prevents a patient’s heart from beating too slowly, if the electrical noise is read as the heart beating, the device may interpret that it’s not needed and shut itself down. “If the patient needs the pacemaker during the procedure, that could be a very bad thing,” says Curtis.
Curtis adds that for patients who may have an implanted defibrillator, a device that can sense whether the heart is beating dangerously fast, there is risk of the electrical noise being interpreted as a cardiac arrest. As a result, the device could deliver an unnecessary shock to the patient’s heart. “Patients should also know that the magnet will heat up anything that’s metal,” she explains. “The metal tips of a device like a pacemaker or defibrillator which are touching the heart could heat up and actually damage some of that heart tissue. This can also prevent the device from working accurately in the future.”
While an implantable device can put a patient undergoing MRI at great risk, the frightening reality is that many patients are unaware of the danger. In fact, a recent survey by the National Council on Aging found that four in 10 patients and their caregivers were unable to recall whether they had been advised regarding the risks associated with an MRI when they received an implantable device. Even more alarming, the survey also found that three in 10 pacemaker patients had undergone an MRI despite these risks. Among that group, nearly 20% reported experiencing problems with their devices following the procedures.
“There is a real lack of awareness and that’s a serious issue,” says David Bello, MD, a cardiologist at Orlando Regional Medical Center in Florida. “There have been reported deaths and yet there are still a lot of people who don’t know about the risks. In fact, even a lot of providers are unaware. That’s why it’s so important to get the word out, especially considering the fact that there are more people getting implants and that medical imaging is a fast-growing technology.”
In that chain of responsibility, the imaging center personnel should make it a practice prior to performing a procedure to ask patients whether they have an implanted device. In some cases, this is the last line of defense. Gilk shares the following story that was recounted to him by an MRI staffer:
“There was an older woman who was brought to the imaging center by her daughter, who planned to accompany her mother only during the prescreen. As the MRI staffer went through the questionnaire of what Mom had filled out, he noticed she had answered ‘no’ regarding having had any implanted devices. However, the staffer noticed some unusual hair growth patterns around the back of the skull and reiterated the implanted device questions, stressing that if she had had an aneurysm clip implanted, that it could potentially be torn out by the magnet.
“Mom insisted she never had any such procedure, but the staffer noticed the color drain from her daughter’s face. When Mom went back to get ready for the procedure, the daughter explained that several years earlier her mother had had a stroke and had three [aneurysm] clips implanted. But because she didn’t want her mother to know how serious the stroke had been, she was never told about the clips. Of course, the technician read her the riot act, expressing how serious this issue was and how her mother could have died in the MRI machine had this information not been brought to light.”
As this story highlights, it’s critical that patients are cognizant of their own medical history. And if they suffer from memory loss or other mental conditions such as dementia, then it’s crucial that primary caregivers not only be fully aware of their medical history but also become knowledgeable regarding the implications of that history for future procedures.
But what this story also emphasizes is that implanted heart devices are not the only cause for concern in medical imaging. An older adult with any implantable device, including items such as cochlear devices or internal clips, should be clear on whether it’s safe for them to undergo medical imaging. “The problem is that there are so many minimally invasive procedures done today that patients may not consider surgery,” says Gilk. “For instance, when a polyp on the intestinal wall is snipped off, it can bleed and a clip may be implanted. That can potentially become very dangerous in an MRI if it’s a clip that’s magnetic. Yet if there wasn’t a team of surgeons involved or a whole bunch of stitches, a patient may not even consider that procedure surgery and forget to even bring it up before an MRI.”
For instance, says Gilk, renal function frequently diminishes as people age or as they develop age-related illnesses. “This isn’t a risk for getting the MRI exam itself but can be a risk for a rare reaction to the gadolinium-based contrast agent which is typically injected for a select set of imaging studies to help the MRI scanner better differentiate similar materials. Some gadolinium contrast agents have less risk than others and for people with reasonably healthy kidney function, the risk virtually disappears.”
Patients should also be aware in advance that they may be required to lie still or in an uncomfortable position during the scan, depending on the test and the location of the area being imaged. Gilk says this is something professionals and caregivers can help older adults plan for in advance. “If they know the test is going to require them lying still for eight minutes, the patient and/or their caregiver can get out a yoga mat and see how they do,” he says. “If they find the longest they can lay [sic] still in that position is only for five minutes, maybe because of arthritis or other pain, then they can discuss this when they go in for the appointment. This is the sort of thing that helps the patient feel empowered. They know what to expect and they are able to engage in a conversation about it. The imaging facility may be able to help either by providing a sedative or perhaps offering padding. Being prepared in advance makes the patient feel less anxiety going into the procedure and more comfortable during the procedure.”
The Informed Patient
It’s a catch-22 that finds both implantable devices and MRI tests can offer lifesaving options, yet the two interfere with each other and the lifesaving potential each can provide. But a candid conversation with a physician can help determine the best course of action. “The risks of any procedure in medical imaging first need to be weighed against the benefits of the information provided by the imaging in terms of diagnosis and treatment,” says Pate-Schloder. “In regard to implantable devices, they are only a risk for MRI procedures and, in most cases, MRI is not risky at all. But in the case of implantable devices and MRIs, an alternate procedure would likely be recommended.”
Curtis says having a discussion with the physician may lead to a new course of action. “There are alternative imaging techniques like CT scans, which sometimes will provide adequate information and are not a risk for an implanted device,” she says.
In addition, Curtis says, an important message to convey is that if older adults need an implanted device, they should certainly get it. She says patients shouldn’t be deterred from obtaining these lifesaving devices because of a potential need for a future MRI. The key is awareness, not fear. “And this may be a given, but if you are already aware that you need an MRI, get those scans done prior to having the device put in,” she says.
Pate-Schloder adds that things can change quickly in the world of medical imaging, so it’s important for patients and their caregivers to stay up-to-date. Just because a patient may have already had a particular test doesn’t mean he or she shouldn’t have a current conversation with their physician.
But the best thing that practitioners and caregivers working with older adults can do is to encourage patients to be their own health advocate, says Pate-Schloder. “Encourage them to take charge of their medical care and to ask questions. Most hospitals have patient information pages on their Web sites that can be very informative.” She recommends visiting the American College of Radiology’s patient Web site at www.radiologyinfo.org for more information. It can help patients and their caregivers become more familiar with tests and develop a list of questions for their physicians.
— Lindsey Getz is a freelance writer based in Royersford, Pa.
• Pacemakers, cochlear devices, and internal clips can create problems in MRI. Physicians and technicians need to ascertain their presence and make appropriate determinations regarding their safety during procedures.
• Older adults and their caregivers should be aware of their medical histories and provide information to imaging professionals related to any implanted devices.
• Always encourage patients to ask questions. When alternative procedures exist in potentially risky cases, explore other options.