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QI: MR Safety: Case Based Approach to Scanning Pat ...
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And so I'm going to start out talking about safety assessment of patients with active implants, really focusing on the non-cardiac implants. So just an overview, we all know there's a little bit of danger here. So for passive implants, it's mainly heating and possibly movement. No one likes to have a foreign object moving through their body unnecessarily, and heating from the inside out, never a good idea. Active implants add the extra thing of a malfunction. So for instance, there were pain pumps that, when they were scanned in certain ways, would empty their entire, or I'm sorry, medication, drug pump, that would empty their entire reservoir instantaneously if they were scanned the wrong way. So this is a known thing that the FDA dealt with, but there are other types of malfunctions that occur, and that's a danger. So where I'm from at Mayo, Arizona, this is our workflow. So the order comes in, and it's triaged by our MRSO, which is usually a tech who has advanced knowledge of MR safety. If it is for cardiac, then it goes over to EP clinic, and between the tech and EP, we have blanket policies, and they take care of the triage and getting things going. I'm going to concentrate on the non-cardiac part. So what goes on next is that the tech goes down and says, okay, I'm going to collect all the data I need for the assessment. And then if we have some blanket policies, they'll make the assessment right there. If not, then they take that information and they send it over to MRSE, which is MR safety expert physicist who also has more advanced knowledge of MR safety, and they are going to assess whether or not this scan can go forward. And if not, then it will go to the radiologist, because only a physician in our practice is allowed to say no. They can either say scan off label or no, but physicists does not make that final determination, because we don't understand the benefits, only the risks. If it does go forward, then we'll modify protocols as necessary to make sure we have scanning and someone else will talk about that a little in the future. When you're doing assessment, it sounds silly, but the most important thing is to follow the manual. I purposely blurred this because I wanted to make sure there was no copyright issues. But you might say, okay, well, that seems really simple. Why are we even talking about it? This is only for MR safety. This is the manual. This is not the operator's manual or anything else for this device, this implant. It is 38 pages long. So that is why we talk about the difficulty of doing assessments. Not only that, but this is basically the vendor saying, we'll take the liability if you scan under these conditions, otherwise you're on your own. So you can scan off label and you'll get talks about that, but you're on your own if you do so. And I want to point out very importantly, this is from Medtronic. This is from their manual. It says, copies of these MR guidelines may not be the most up-to-date version if not received directly from the website or in another manner from Medtronic the same day of the patient's MRI appointment. So it's not just you need to have the manual, you need to have the manual the day you're going to scan them and make sure that everything you assessed still applies. And we have a little poster on that if you're interested what happens when that doesn't happen. Okay. Is it really that much work? If it's the simple ones that the tech can kind of collect the data, we have a blanket policy, it's about 15 minutes of extra work. Go to the complex ones, just collecting the data is about 30 minutes. And then the assessment that the physicist does is about another 18. And then scanning is typically about 60 minutes of work between the physicist and the tech and everyone kind of making sure everything is the way it needs to be for the scan to go forward. I'm not going to do much on off label, but I will mention since probably a lot of radiologists in the room, the data that I have for off label is about 15 minutes to do off label assessment. So I want to do one case here. This was an urgent ER order, so as a result we get paged automatically whenever there's an urgent ER order. This was worsening back pain, leg weakness, and urinary incontinence. They wanted an eval for cord compression and cauda equina syndrome was suspected. For those of you who don't know, that syndrome is basically, it affects multiple nerves down in the sacral region, lumbar and sacral region, and requires emergent surgery. They had a neurostim, which you can see here, as well as some passive spinal hardware. So they wanted an L spine, so one of the things that had to be considered is, is the artifact going to make it impossible to scan this thing? I mean, are we going to be able to get any kind of diagnostic information? You might think, oh, it's just heating, right? Well, the heating actually isn't that bad. It's something called normal mode, so it's actually pretty easy with the heating requirements. And we're doing it on 1.5 Tesla, so that's not the problem. But this is all the other stuff, well, no, it's actually, this is a subset of the other stuff that we consider when we're assessing it, because this is what the manual says you have to consider when you assess it. Do they have other kinds of implants? Sure. You're not allowed to use blankets. Make sure you don't throw them on there. All right. Is the patient febrile? Do they have a fever? If they are, that's considered off-label. You're not allowed to scan them if they have a fever. No non-hydrodyming, that's not a problem here. No TR coils, again, for lumbar spine, not much of an issue. In terms of the device, we have to program it correctly. You can only use circular polarization. So there's all these things. It took 30 minutes to record the data and 40 minutes to assess to make sure we really tamped down everything that can happen. And for this one, you needed to have a remote control in order to determine whether it could be scanned. Because it had to happen at the point of scanning. The remote control of the device told you, you're scanning yes or no. So this was the final image. It turned out they did have a couple things. I'm not going to read them off here because I'm out of time. But essentially, it turned out they did not have that. They did not require emergent surgery. They started looking at whether or not the electrodes were placed correctly. And so in some sense, there was a relief. It was something that was information that was needed for this patient. And yes, you can see the artifacts. But our physicists assessed that they weren't going to be so bad that it was going to be non-diagnostic. And so it came out with a good ending for this patient in terms of not needing this emergent surgery. So just a little bit on how we do this. And then at this point, I am going to stop now. And I will hand it over to our next speaker, Maureen Hood, who will be talking about cardiac active implant assessment. Well, good morning. It's always an honor to be here at RSNA. And I'm delighted to be able to talk about the scheduling issues around active devices and specifically cardiac. First and foremost, as the previous speaker alluded to, you have to have written policies. You have to have guidelines. Those are absolutely essential to minimize the risk to the patient and also to make your workflow work well. MR safety starts at scheduling. And whether you're allowing online scheduling in your place or whether you're using real people, it's absolutely essential that you have a mechanism to be able to catch all those implants inside the patient's body, especially the active ones. In our site, all of the cardiac patients that have active implants are handled specially with our MR safety officer. And this actually maximizes the safety and maximizes the throughput of the patients as well. Okay. So screening for this falls with our MR safety officer. And if it's a complex or multiple implants in the body, then we're now reaching out to our MR safety expert as well. But at the end of the day, the decision in our facility is the decision whether or not the patient gets scanned is with our medical director. A lot of those are in a blanket policy put in place that the MR safety officer can then just follow, but it's ultimately their decision. And these things are documented as well. Some important safety considerations. So when you're the MRSO and you're thinking about whether or not you have the ability to even scan this particular patient, you have to look at the device and know all of the equipment that you have, all of the scanners you have in your facility, and decide whether or not the conditions for that specific cardiac device is something that matches what you have in your facility to be able to scan the patient safely. Because you have to be able to meet all of the requirements, as he pointed out earlier, it could be up to 38 pages or more of information you have to go through. It's also important to look at a few other things. Does the device require programming before and or after the scanning that be done? And also, do you need monitoring? Because if you need those things, you now have to coordinate additional people to come in for that particular appointment with the patient that's going to be scanned. And also, does that particular device, and for our cardiac devices, they're all done on day shift, Monday through Friday only, but some devices are not that way at our site. So for a case example, and this is one of my favorites, patient comes in, wants to get scheduled and they say, I want a Saturday appointment because my doctor told me my pacemaker's MR safe. And we all know that's not going to be true. So the MRSO then goes and looks up the device, checks the make and model, checks the leads, checks to see if there's any other devices in the patient's body. And then also at our site, was it referred by cardiology or another provider? Here's a subset of the types of things that the MRSO's going to be looking at. And one thing you're going to notice on this one is there's no B1 plus RMS. So this is probably a slightly older device and it's only approved for 1.5 Tesla. So if you're one of those sites that has multiple scanners, but they're all 3T, you just have to be mindful that sometimes you're not going to be able to meet the conditions for MR conditional on that particular device. And that's when you bring in your MRSD and MRMD to make those other kinds of decisions. So at our clinic, we have multiple scanners and we happen to have three 1.5 Tesla scanners. So this was an easy way for us to be able to meet those conditions of that particular device. And our patient was not referred by cardiology, so we're now working on coordinating with the vendor. We actually have specific vendor days because we do a lot of devices at our site. And so we're now going with the vendor, getting data that they're available, also going with the nursing staff, figuring out what they're available. And then the MRSO gets to call the patient up and tell them the bad news that they can't have a Saturday appointment. So it's important that the MRSO is well-trained and really good with the patients to be able to calm them down and help them understand that, yes, they can be safely scanned at our facility, get the exam that they need, but there's certain conditions that we have to meet. And that means that we have to coordinate with the vendor, we have to coordinate with the nursing staff, and we'll take very good care of them because at the end of the day, we've got to make sure the patient gets the right exam and is kept safe. And a couple of extra things about thinking about cardiac devices. Cardiac devices in a patient are there to save their life and help also increase their quality of life. But because cardiac devices sometimes mean that if the patient has a malfunction that they could die, you want to take extra precautions. So the person monitoring that patient needs to be deemed appropriate to care for the patient in an emergency. At our site, that is an RN with ACLS experience and certification. Some technologists do have that certification, it's great, but they can't give the medications needed in an emergency situation. So that's why we have an RN or higher do that. Also, since these are patients who have cardiac devices, it is my humble opinion that these types of devices should not be scanned at remote, small clinics off way away from a hospital. You need to have emergency rescuing available should something go wrong. Anyway, it all takes teamwork, and we'll wait for later for the questions. Thank you. All right, perfect. Thanks very much. I really appreciate that, Sam. We're going to do a little tag team here with a common set of slides, and I'm just going to get things kicked off in talking about focusing on heating and RF time management, a few tricks of the trade. I'm Scott Reeder from the University of Wisconsin, and my colleague, Yuxin Zhao, from the Mayo Clinic in Scottsdale. So what we'll do in the next 10 minutes or so is I'm going to present some examples, some clinically relevant examples, really dig a little bit more into depth in what has already been presented and sort of motivating this. And then Dr. Zhao is going to go into the remainder of this discussing understanding how heating and burns can happen, discuss some of the factors for RF heating and burns, the different types of burns, and how this is going to impact our protocols, and how to prevent these heating complications, including the patient setup system configuration, and really go into some gory detail about acquisition parameter modifications and how we might approach some of these clinical scenarios. So here's a real-world situation that I deal with at my institution. We have a children's hospital that is part of the University of Wisconsin health system, and we might have a situation where we have a three-day-old premature baby who weighs a kilogram. So a tiny little baby has had this concern for anoxic brain injury, needs an MRI of the brain. And we know from past experience that the SAR monitors on the scanner are going to prevent routine FASP and echo imaging, as well as some other sequences as well. And in our children's hospital, we only have a 3T scanner, so that really complicates things as well. There are possibilities of bringing the patient to other 1.5T systems, and so the question is how one might want to approach this. Case number two. This is not a 27-day, sorry, that's a 27-year-old previously healthy male who had a complicated common-muted fracture of his tibia and fibula from mountain biking, had surgery with the external fixator device, for example, one of the ones that you might see there. He's been in the hospital for a few days. This is getting red and swollen, and there's concern for an abscess at the wound site. And they want to get an MRI to rule out a local infection, or perhaps even osteomyelitis. What happens if the MRI was actually not for that location, but it was outside, the implant was outside the field of view, and perhaps this was in the brain? And also, what happens if the patient might be undergoing general anesthesia? Third example. Deep brain stimulator. These are becoming increasingly common. We have placed a number of these at our own institution. In these situations with an active implant, it's essential to follow the vendor guidelines. When we look up the guidelines, the executive summary is that it is conditional, which means under certain conditions we can scan this. The B1 RMS should be less than 2.0 microtesla. The SAR should be less than 0.1 watts per kilogram, which is quite extraordinary. Can we even do the exam? And with that, I'll hand it off. Yeah. I think that Dr. Rader raised a lot of questions. How can we answer these questions? How can we make an approach? Then we need to understand what's the heating? What caused the heating? What caused the factors? In MRI, everybody knows the RF sequence is the most important to control everything. The RF deposit to the human body, the RF always have two components. One is a magnetic field. It's helpful for generating the images or spectroscopy. But the electrical field is always there, but it's bad. It's generated a heating. Then what's a factor caused the RF heating? We already have three case, actually the typical three case. That's a patient-related, the patient conductivity, permittivity, and permeability, and the size of the mass. Especially the first case, they have just one kilogram of the baby. How can we address those issues? We should consider the patient. Then for the environment, we have a lot of hardware, especially now we have 1.5T, 3T, 7T, Tesla, and also all kinds of coils, and the temperature setting in the MRI environment. That's we need to consider. The third one is the most important for the implant device. We give, for example, the DBS. Then how can we select the right sequence and set the right parameters for those configurations? Then way to monitor the SAR, I think three unit is very important. One is the SAR. The SAR is proportional to the B1 field and the B0 field and the flip angles. That's well known. Another one is called the B1-RMS. I think most of the MRI safety society prefer use the B1-RMS because the B1-RMS, they can give the absolute, those safety issues. And another one is the SED, specific energy dose. That's a total dose absorbed by the whole body exam. Then based on the three case, we can say three points we can generate and we should understand in the MRI environment, the near field, they will generate the higher field. Then if close to the transmitted coils, those area will generate a high RF. Another one is the patient setup. Those is related to the technologist with how to do the patient setup. If you generate a coil, wires, then skin, metal interface, and the skin-to-skin touch, they will generate a different kind of heating. The last one is for the device. We already say a lot of parameters maybe we need to adjust to reduce the SAR. Here I just gave some of the how to heat control in the exam. We need to first, I would say, is it necessary for the MRI scan? Like a premature baby, one kilogram, do we need the MRI? That's the radiologist and the ordering physician need to answer these questions. Then what kind of scanner we need to select? Then if the patient have a device, can we remove the device, then have the patient change the sheet and add the barrier between the patient and the gantry, and in ball fan, you can turn on, then reduce the fan, and also position the patient, avoid the skin-to-skin contact, and make, especially for the technologist, you keep an eye on the patient, if the patient feel uncomfortable because of the SAR or because of some issues, we need to take care for, and also another one I listed here is reduce the SAR from the parameters, like the GIE sequence is much low SAR compared to the FSE, and ensure patient don't too warm, then I think the last one, we can reduce the total scan time, okay, here I just listed our parameters, you can, how to reduce the SAR, you can increase the TR, increase the echo space, and decrease the bandwidth, then decrease the phase encoding, of course here, the most important is the flip angles, you can decrease, then spatial saturations, you can decrease, then most of this is the timing will increase, because no free launch, yeah, then just to give one very specific example, is how to reduce the SAR, for example, initially, the protocols in the FSE protocols, with 44 slides, the TR is 2000, the SAR is 4.5 watts per kilogram, how can we from that sequence go to 0.1, I think on the segment scanner, I will give you the details, how to reduce the SAR, on the GIE, you can set the parameters, but you couldn't set the parameters on TR, 0.1, 0.5, you can set, but 0.1 is not achievable, but in the next version, I talk to GIE, they will give you more flexible, maybe you can get 0.1, here, I just gave a strategy, how to reduce the SAR from 4.5 to 0.1, this time 0.1, the first step, we go to the fast mode, from the fast mode, go to low SAR, then you can reduce the SAR from 4.5 to 2.0, then you can change the flip angles from 150 to 130, you can see the SAR go down to 1.58, then you change the number of slides from 44 to 36, the SAR further go down, then change the TR, increase the TR to 3000, the SAR can go to 1.0, then you change the echo space, increase the echo space from 7.6 to 10, then the SAR further go down, then the turbo factor from 9 to go 4, then you can go to 0.56, then change the number of phase encoding from 384 to 256, you can go to 0.28, the SAR, then if you want to further decrease the SAR, then you can change the number of slides, further increase the TR, then change the flip angle and reduce the SMS, of course, the timing will keep increasing. Yeah, this is the final one, you can go to the 16 slides, TR 7500, you can reach the SAR is 0.1, actually is 0.09. Yeah, this is reference. Thank you. All right, so our topic is the off-label scanning of patients with active implants. I'm from Mayo Clinic, Arizona. I'm from Mayo Clinic, Rochester. All right, so we're focusing on active implants that can be scanned off-label. So by off-label, we mean that we're scanning this patient with this particular device in conditions or a configuration that is not specifically described or tested by the manufacturer. So that means for the physician and the physicist, we have to come up with a risk-benefit analysis. So we have to decide what are the risks of scanning this particular device for this particular patient and what's the risk to the patient and the device, and then also what is the benefit for the patient clinically. So this may require discussion with the ordering provider, the scanning team, and physicists and radiologists and everyone involved. And we have to take into account all of the factors that we've already heard from the prior talks, all the hazards in MR. So these are the static magnetic field, RF heating, our time-varying gradients, and even acoustic noise. Sometimes these discussions will even include our patient as well. And now that we're, you know, you, the vendor gives you guidelines on how to mitigate all those risks for an on-label device, but an off-label device, you have no guidelines. And so you have to critically think about different ways of mitigating that risk, again, considering all the different hazards. A great way to start, though, is if there is on-label instructions for safety, then you can use those as a context for what the hazards are a bit. It's critical to understand the patient's health state, so fever, anesthesia, even the equipment's going to matter, so 1.5 Tesla versus 3T versus stronger gradients, weaker time-varying gradients of a system. And one of the key ways of mitigating heating risk is to use a clever use of transmit-receive coils. So in this diagram, there's a body transmit where it's a larger volume that's being heated versus a smaller volume with a head transmit-receive only coil. Our exams are sometimes monitored by an MR safety expert like myself and my colleagues, where we can, as Dr. Zhou expertly showed, manage those heating parameters. And then he also guided you, Dr. Reeder and Dr. Zhou guided you through ideas of reduction, so fewer series that are being acquired, less SAR, less BMR and RMS, and less time. And it's worth noting that the typical off-label device at our institution is going to be a cardiac implantable electronic device, CIED, and their abandoned leads. So the MRI hazards are described as being low at 1.5 Tesla, and we also at Arizona scan off-label devices with MRSO oversight. They have training from the EP clinic, electrophysiology clinic, on monitoring them, and there's, of course, life-saving support nearby. And then we also will scan off-label. Well, there is no really labeling for abandoned cardiac leads at 1.5, reduced from normal mode. So normal mode is 2.0 watts per kilo. This is a little bit less. And again, as was also described by Dr. Hood, the main risk we're concerned about is the cardiac risks, less so the MR risks. And a model of how we go forward in our institutions is the MRSO, who is a technologist and a safety expert-like physicist. We gather information about the patient state and that MR order, the device that's in there, as well as the equipment that's going to be used. And then that is presented as a package to the radiologist for a risk-benefit choice. As Dr. Sinzikovic has a poster about kind of putting that in a package, so you can go and check out that poster. So once all this information is collected, often this is presented to the radiologist for that final decision. Now, this may include the radiologist talking to the ordering provider, certainly a back-and-forth discussion with our scanning technologists, sometimes vendors, and sometimes our physicists as well. So this is a collaborative effort, but in the end, it's the decision of our radiologist to either go ahead or not go ahead with off-label scanning. All right. A couple cases. Yeah, so Dr. Brook-Walter, our first case coming in, is a MR brain order. They had memory loss going on. They did have a previous MR lumbar spine in 2019, and this is a description of the device, and the on-label is fairly easy to accommodate, those heating parameters and timing. However, they also have received a radiograph that shows migration of the leads up here. And critically, in this case, this previous MR exam does not really imply the safety of future exams. So once all this data is collected, I heard about this case, and I ended up talking to the ordering provider for this particular patient. Now, in the end, the ordering provider in the discussion decided the patient may not be able to sit still for this exam, so he decided to do a CT head instead. Now, that being said, part of this discussion was we can safely scan this particular device because we are scanning a head and can use a transmit-receive coil, so we could have done this exam safely. The ordering provider decided that the clinical benefit of the exam, perhaps the patient couldn't sit through it, decided not to go through with it, but not at this point for the risk side of things. And a companion case next. Yes, to contrast that example, here's another kind of similar one where there's an MR brain ordered, but in this case for intractable epilepsy, so it's presurgical guidance. And so there's a different device. In this case, it is nonfunctional, and normally its on label would be easy to accommodate. It has an MR safe mode. In this case, you can never reach that, and the vendor says this, therefore, is off label, and they would not advise scanning it. A proposed solution, though, in this case, is to, again, use that head transmit-receive coil, which is going to limit the RF to that head region. And critically, the device doesn't involve any leads, or any implanted generator that is in that head region. So the risk-benefit here is that this patient could sit through a longer exam time. It was needed for their clinical treatment, so this was surgical planning for epilepsy. And, again, the risk is quite low using that transmit-receive coil since we can limit the heating to that device by using that transmit-receive coil. The device was only deposited in that short, small area in the head, but not so much where the device is. So these are a couple of just examples of a successfully completed exam for this patient. And our last exam is an MR urogram investigating hematuria, and there are two active devices. So there is an on-label pacemaker, and there's also a spinal cord stimulator. And in this case, the spinal cord stimulator has its on-label heating and timing parameters are very restrictive. And then the addition of that other active implant makes it technically off-label too. And so it will be difficult to do it even with the on-label of the spinal cord stimulator. We did also investigate the location and orientation of... So here's leads from the spinal cord stimulator that you can see on the left image. And then there's CT showing where the generator's implanted, and then the CT localizer showing the leads are separate. They're physically distant from where the cardiac device is. So at this point, we think that both devices can be scanned safely. They shouldn't interact with each other. We think the risk of the patient is low using the conditions for the more restrictive device. So we did go ahead and scan this patient. Just to reduce the overall scan time, we did require several fewer series, but we're still able to take a good look at this patient and get a good diagnostic study for this patient. So today we talked about how to kind of go through that risk-benefit discussion and perhaps that interaction between the physicist and the physician and how that discussion sometimes goes. But it's really important to have that discussion evaluating that risk-benefit discussion for off-label devices. But we can safely scan devices off-label when we consider the hazards and limit and mitigate the risks. Thank you. I'm Drew Bowman, one of the MRMDs from Mayo Clinic in Jacksonville, Florida. I'm being joined by Andrew Panda, one of the MRSEs from Mayo Clinic in Arizona. So now we're going to talk about what happens when an incident occurs or a near-miss occurs. So this is, you know, the cheerful part of this talk, about when an actual event does occur, what do you do about it? So when talking about MR safety events that we track at Mayo Clinic, this is throughout all of our sites. There are basically four we look at. Device issues, which you've been hearing about the whole session. For us in Florida, most of the time, this refers to people who show up for their scan with a device we did not know about, and we have to kind of figure out what we're going to do. Internal injuries, burns. Burns remain the most common safety event reported by the FDA. Third, ferromagnetic objects that get into Zone 4, into the magnet room itself, and then the most dreaded ones, the projectile events, when things actually fly into the magnet. And so there are other events we track as well, but as far as MR-related, specifically to MR safety, that are unique to that environment, these are the four we concentrate on throughout the enterprise. So if an event's going to happen, be prepared, right? Before an event occurs, have a plan. Know what to do, who to communicate it to, and then when should you do that. Really, this plan should be sort of created in conjunction between the MRMD and the chair of the department, and that should kind of come down from them. The Mayo Clinic Florida plan for events is this. If there's a projectile event that strikes somebody, patient, staff, or anyone, take care of the patient, make sure they're okay. Whoever gets hit, make sure they're okay. Then the MRSO, the MR supervisor, the MRMD, and the department chair will be notified within an hour, every day of the year, every day of the week, in 24 hours a day, no exceptions. We want to know about this fast. We may not do anything specifically, depending on the injury, but we still want to know about it quickly. A projectile event with no injury, a zone 4 breach, a thermal injury, because it always takes time to know how severe a burn will be, take care of the patient, and then notify the MRSO, MR supervisor, MRMD within 24 hours via email or, you know, in person, depending on the time of day it's going to be. It's a little bit less acute as far as how you're going to handle this. So, of course, an example of an event, something that I actually had to deal with a little while ago. So we had a patient presented for an outpatient abdominal scan. The patient sat on the MR table, began to lie down when the locker key in her hand was pulled out of her hand into the magnet bore, and it hit her in the head on the way into the magnet, just right above her right eye. The key was removed from the magnet, but the patient proceeded with the scan because she felt okay to proceed going from doing this. And then I was notified during the scan from the MRSO. The tech notified the MRSO, then called me. So what did I do when all this happened? So, first, I called the tech while the scan was going on, asked if the patient was okay and, you know, his version of events of what happened. I asked the tech if he was okay, and this would rattle anybody. So this is a seasoned tech, over two decades of experience, but he has a job to do too, and I don't want him to be so upset about what happened that he's unable to perform that function as well. And to know that he is supported, these kind of things can happen in that, you know, how is he doing, how is he handling the process of the time. I asked him to bring the patient to a recovery room after the scan was over, where I evaluated the patient myself. I was noting the chart, documenting the event. You know, basically, the patient had a small scratch on her right upper eyelid, a little bit of swelling. She had, you know, normal vision, normal ocular motion. She really was okay, aside from the scratch. So if we were off by a centimeter, this would have been a total disaster, but unfortunately, she was doing fine. And I referred the case for root cause analysis. So what was to happen? What was the problem? This was our culprit. This was our locker room key. Now, locker room keys are, you know, where the patient stores their clothes, attached by a wrist bungee, and the keys are all non-ferrous. The problem in this case was the ring was ferrous, and that's what led to the projectile event. And so when asking, doing the root cause analysis, what led to all this, our practice had been for the patients to carry the key into the scanner room, hand it to the tech, and then they hang it on the wall in the scanner room so the patient knows that their key is secure and their belongings are okay. So after that, you know, discussing the tech, saying, what should we do about this, they mentioned, well, you need to make sure that the wrist bungee is always attached, all the keys are non-ferrous. I was sort of like, why are we bringing keys into Zone 4 in the first place? So there are different things we can do to address this problem. The big one for me was make sure the locker keys are outside of Zone 4. Now, how would we approach handling this was that we actually then created a little platform outside of Zone 4, this is the outside going to the magnet room, with a little hook for the keys to be placed on, as well as a little bin for glasses or any other last-minute items the patient has to get rid of. So what we would do is upon breaching Zone 4 itself, we would stop and ask the patient, give me your locker room key, and if anything goes on, you need to take it off right now, and that's what we would do going forward. And with that, I want to stop and hand it over to Dr. Panda. Thank you, Dr. Bowman. So when we were going through cases to share, we covered a bunch of cases and thought this would be a good one to present because I know everybody has been talking about patients and devices and implants. Another factor that affects safety is folks who are in our room who are not particularly, might not have MR training. So one of the areas where we find a lot of safety incidents in our practice is when we have anesthesia team or teams outside of MR coming in to provide patient care in the MR environment. So that's, of all the things that you deal with, that's another factor that compounds, and we have to be mindful of that. So with that background, so this is the incident where we were planning to scan a patient under anesthesia. After the induction in Zone 4, prior to scanning, anesthesia nurse rolled an IV pole that just happened to be there in the room. Now, the IV pole became attracted. The patient was immediately moved, so no harm to the patient. But the nurse ended up injuring her arm because, her finger, and that's where the impact was, the pole and the magnet. Then the service team was called. The entire MR leadership was informed, and we were able to remove the pole without having to quench the magnet, but that was an interesting experience to go through. So I would not recommend participating in that type of experience if you can avoid it. So after the incident, the big part is to figure out what could have been done right going forward, but to Dr. Bowman's point, leading up to it, we have to prepare. We have to anticipate these things will happen, and our practice had anticipated that these things could potentially happen, and we had done preparation. So believe it or not, we actually have cameras that look into our Zone 4 entrance for all our scanners. So we are constantly monitoring who is going in and out of those rooms, and there's a historical record that we can go back and look at what activity was happening in the room. We have physical barriers that only MR techs are allowed to operate, so they are the ones who are providing access to anybody going into the room. We have labels on these IV poles that specify whether they are MR conditional or not, and most importantly, anybody who goes into MR Zone 4 has to go through an extensive training, including hands-on safety training. So this incident happened with all this preparation in place, and the staff who were involved had gone through all this safety training and were aware of all the safety procedures. So part of the practice is when we do have incidents like this, we have a standardized way of approaching this, and the big part of it is the teams come together and we all sit down around the table and do a review process, and the review process, all the stakeholders essentially bring where they thought the gaps was in the process, and we list it down, and there's multiple meetings and discussion, which then leads up to, okay, what are the risk reduction strategies and what should be the follow-up process? So the three big action items that were identified by the team based on this incident, number one was the labels on IV pole were there, but they were not, you know, prominent enough that you can quickly say that this is an MR conditional IV pole or not. So this IV pole that became attracted actually didn't have any label on it, but we have all this mix of IV poles. If you're quickly looking at it, you won't be able to tell whether one of them is MR conditional or not. So the first action item was there was no good distinguishable way to identify which IV poles are MR conditional, which ones are not. The second one was, so we do have a 200 gauss line marking on our scanner rooms that as part of our safety training, we tell folks to keep things outside of that 200 gauss line because that's where things get really, really attractive, but most of the scanners, it was only at the front of the magnet because that's where we thought most of the risk for the projectile comes from. We had not thought about back of the magnet can also pose the same risks. So that was another action item that was mentioned that, okay, having a 200 gauss line across the entire magnet. And the third, which was the biggest gap, even after having all those cameras, we still couldn't figure out how this IV pole made its way into the room. I mean, we looked at, our team looked at 190 hours of security video and we still have not figured out how it made its way. All right, so the resolution. So the first action item, so now all our IV poles have these yellow tops, yellow for MR conditional, and that's a quick view for anybody using the IV poles in MR rooms that those are the only MR conditional IV poles that are permitted to be in the room. And also if there is any IV poles in the room for folks to quickly know that those shouldn't belong there. And then it was actually quite an expensive fix. It took just $90 per IV pole to get them anodized. And the second one, all our new constructions, now we are having this 200 gauss floor marking with the label that spells out 200 gauss around the entire magnet. So all our new construction, that's part of our standard installation. And last check that we implemented is a daily sweep of our rooms where the morning tech and the evening tech at the beginning and the end of the shift, they go around and look for any unknown items that might have sneaked their way into the room, like what happened with that IV pole. And sure enough, six months later, we found another IV pole in the room. But fortunately, this was part of the sweep that was identified that one of the techs when they were doing their evening shift. So having the processes, but then also controlling the processes is kind of the key to maintaining the safety practice. With that, I hand it back to Dr. Bowman. All right, thank you. Rob, now quickly, so if an event happens, do you need to report this? And if you report it, to whom do you report it? Any event that results in serious harm or death, death obvious, which we need to report it to the Agency for Healthcare Administration, the Joint Commission, and maybe a state agency, depending which state you live in. That's variable and depends on where you're gonna be. There's a couple of references that we've had from before from Florida and Minnesota about how this would happen. What is covered by events that cause, quote, death or serious injury of a patient associated with introduction of a metallic object in the MRI area, events related to material inside the patient or particles outside the patient, items or projectiles, whether or not the staff know that they are there, and captures events as a result of projectiles, which can include retained foreign objects, external projectiles, or pacemakers. So really, it's pretty all-inclusive, as one might expect. So I guess as a summary, we would both agree, is that have a plan for managing an event before one actually happens. Evaluate your safety process to identify areas for improvement when these events do occur. I mean, at least try to make, you learn something from these events to make the practice more safe. And know that AHCA and the Joint Commission must be notified when a serious event occurs. And if you are unsure, I would suggest you run it by your risk management department. With that, thank you for your attention.
Video Summary
The video transcript discusses the safety assessment protocols for patients with active non-cardiac and cardiac implants undergoing MRI scans, with particular emphasis on malfunctions and heating concerns. The workflow at Mayo Clinic involves a triage system where initial assessments are conducted by a specialized MR safety officer (MRSO) or an MR safety expert (MRSE), potentially involving radiologists for final decisions. The presentation stresses the importance of following detailed device manuals, ensuring the latest guidelines are used on the scan day, and modifying scan protocols to minimize heating and movement risks. Additional sections cover real-life scenarios and the logistics of scanning off-label patients, along with the role of teamwork in implementing safety measures.<br /><br />The subsequent segments explore heating control strategies in MRI, demonstrating how protocol adjustments (like reducing SAR and B1 RMS) and patient setup affect safety. There’s an emphasis on risk-benefit analysis for off-label scanning, illustrating with case studies the necessity of comprehensive collaboration and communication between medical staff. Finally, the video underscores the importance of a preemptive plan for potential MRI safety incidents, detailing the investigation and amendment process after such events to improve safety protocols.
Keywords
MRI safety
non-cardiac implants
cardiac implants
Mayo Clinic
MR safety officer
heating control
protocol adjustments
risk-benefit analysis
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