 Thank you. I would like to start by thanking the organizers for inviting me to be a part of this wonderful academic program. So, why should we speaking on MRI safety today in this 20th MRI teaching course? So, as you know, MRI is safe, but if something goes wrong, as it says, it can go very wrong. As far as safety concerns, if MRI is concerned, you remember the famous unfortunate case actually, he was back three years back when a man died in Mumbai's hospital. I was stuck to the MRI machine for four hours, actually was an attendant to a patient who was to undergo an MRI. Unfortunately, scum that once again highlighted this serious safety issues of MRI. It actually dates back to 2001 and nearly two decades of past, you'll see that a six-year-old boy died of skull injury during MRI. And this is what actually prompted the American College of Radiology at that time to develop a new ribbon panel of MRI experts, which included radiologists, physicians, PhDs, technologists and representatives from corporate after years in the law profession. And they published the white paper on MR safety in 2002, actually, which was the first document. And this was subsequently revised in 2013 and forms the basis of the current recommendations, right? So coming to MR safety, actually, there are a lot of issues which can occur as far as MR safety is concerned, which includes projectile injuries, which I just mentioned a while ago. This could also include issues with implant, quenching of MR, use of MR contrast, medical emergencies, heating, serration in graduates, and acoustic noise as well. So I'm going to take you through them one by one, okay? So let me introduce to those magnetic fields. You can have three different types of effects. One is because of a static magnetic field of the magnet. This is what give rise to the devices, implants and projectile kind of injuries. Second would be the effects because of the radio frequency pulses and this leads to heating of tissues and thermal injuries. And then is the magnetic field gradient, which can cause nerve stimulation injuries or acoustic noise. Let's start with the effects of static magnetic field first. So as you know, as seen in this picture, there's a coil around the axis of the board, right? And the magnetic field inside the board is nearly 10,000 to 100,000 times the magnitude on the Earth's surface. So as you know, this is a mostly liquid helium and once established, the main magnetic field remains on for several hundreds of years. There's a 5G line, which as per the US FDA 2005 norms, which is usually marked inside the MR gendries in all the US, right? As you can see, there's a red line here at my own Institute here. So this is the upper limit where the field strength is of no potential concern for the general public. The field really drops to point triple 05 tons, but this does not safeguard against projectile incident. So this terminology should be aware of a 5G line. The effects of static magnetic field causing safety issues is because of the attraction of the ferromagnetic material towards the magnet. And this can call projectile injuries or biological changes. So if the magnetic field strength is less, you don't have no serious cardiovascular effects. They might mild increase in ambiguity waves, but above 2TT, above 2 Tesla of MRI magnet strength, they have been reports of fatigue, headaches, hypertension, irritability, and problems in imaging in sickle cell and immune patients has been reported. Now projectile injuries, these are ferromagnetic metal objects, and hence attractive to the metallic board. And of course, this is proportional to the strength of the magnetic field strength, higher the field strength, higher the chances of projectile injury, distance from the magnet, how near it is to the magnet, and the mass of the object, right? Now you can have various devices or implants, which can cause projectile injury. This include aneurysmal clips, spinal fusion devices, cardiac pacemakers, cochlear implants, hearing aids, heart valve processes, dental implants, vascular and cardiac strength before six weeks. So we have certain safety recommendations for this. You need to have an installation of metallic detector at the entrance of the MR imaging suite, so that it beeps whenever something metallic goes inside. You need to do some kind of an MR shielding. And importantly, educate all the healthcare personnel and associated staff about the possible hazards with ferromagnetic materials. We have MRI facility zones in safety recommendations, right? So we have four clearly labelled distinct zones. I'm going to show you what they are. And this is to restrict the potential ferromagnetic materials in MRI scanner room. The four zones are labelled one to four and assesses progressive. So zone one is freely accessible to generally public and usually just outside the MR environment, right? Outside the MR environment. Zone two is actually the interface between the outside and the inside magnet and usually includes reception, patient waiting area, toilets, nursing station, patient history room, right? Now zone three or four are the restricted zone and only screen people allowed entry into this. It's where you need to be very strict with this. And this should be clearly demarcated with a notice. Zone four is actually the magnet room. And it is marked with a red line and lighted sign which shows the magnet is on. So in line of sight of level two personal and MR technologist and there should be video cameras to monitor the patient head in. It should be equipped with MR compatible resuscitation equipment and 5G line should be clearly marked. So after the static field just looked at the effect of the changing the gradient field, as you know, they we have gradient coils and so magnetic field gradients to encode the MR signal. And we have rapidly changing currents for microscopic movements and coils. You can have a caustic noise that is knocking and buzzing sounds and peripheral nerve stimulation. So caustic injury, there is a potential for permanent hearing impairment and temporary hearing impairment has been reported. In fact, FDA has set up a limit of 140 decibels MR per system. And if you're doing with a hearing protection, that's around 99 decibels. So temporary hearing loss has been documented in patients who underwent routine MR imaging examinations without protective devices. So this is your standard MR 108, whether rock concert will be around 120 decibels, right? So again, as far as safety recommendations for caustic injuries concern, use of disposable earplugs are recommended or over the ear headphones or defenders. This can attenuate the sounds by 10 to 30 decibels. The earplugs are must in all units, all right? When peripheral neurostimulation effects, you can have arms and legs, specifically showing pain and needles or severe pain. And every recommends that decibel per dislodged pen be set to levels that do not result in peripheral neurostimulation without a specific right. This is great at greater risk for those involving the high bandwidth rate outside. Rapid gradient switching. Magnetophosphines, what are these? These are an equational phenomenon. Patient will note unusual visual disturbances during MR scanning. We'll have stars in one eye or light flashes. And the result by induction from changing gradient feeds. While radiofrequency heating is the biological effect of radiofrequency absorption, right? Maximum at the surface and minimum at the center of the body. And again, every has defined the limit the body core increase of one degree. Had if the hand degree, if the hand increases to 38 degrees Celsius trunk 39 and extremities increase to 40 degrees. This is a upper limit of the prescribed FDA limit for it, right? Of course, we have specific absorption rates, calculation FDA has defined limits for whole bodies where it should not be more than four. And rest all of the cases 1.5 watts per kilogram. Now burns have been reported as well. External objects, coil ECG leads can form conductive loops and heat up the tissue. And specifically, it might be an issue with transdermal patches with traces of aluminum. It should be removed or away from the coil. Tattoos might be an issue, especially darker rings which are rich in iron oxide can cause to local skin build the tanks. So safety recommendations includes proper screening of patients. Change out of street clothes, avoid skin contact, no crosslights, no arms on hips, no cross arms. Don't coil the cables, keeping them in straight line, lower star wherever possible, manufacture protein padding and eyes and ears on patient at all times. As well as pediatrics is concerned, this, this is a slightly different ballgame, right? The kids are more vulnerable to anxiety. So you would have sedation. Your kids might need sedation at times. You can use of a mock MRI scan, let me show you one. Then motion artifacts again, will be an issue and sedation would be required and go in neonates. You need to have ear plugs in all kids, neonates. So as I said, sedation and monitoring is an important topic for pediatrics and this is essential for good quality images and proper sedation would be required in children for a good quality MRI, right? But for all these ones, remember temperature monitoring is very important and resuscitation equipment should always be ready. Same thing. So this is a mock MRI scan and this can alleviate need for sedation, especially in the kids who are a bit more receptive and then the age group of let's say five to ten years, right? Really, no, it familiarizes the child with the procedure and the child can lie down comfortably during the scan and probably avoid sedation at times. And as I have already said, acoustic noise in neonates is because of immature anatomical development. There's increased response to acoustic stimuli and can elicit autonomic instability in both terms and preterms and you must use an ear plug in all units, right? What about pregnancy and MR exposure as yet no harmful biological effects of MRI has been reported but the FDA recommends if the normalizing imaging like ultrasound is suboptimal or if the information to be gained by MR would have required more invasive testing like radiography, CT scan or angiography. In that case, MR is susceptible. For healthcare practitioner pregnancies, they're permitted to work no issues. For patient pregnancies, MR is risk-free during pregnancy but MR contrast agents should not be routinely performed to pregnant patients. I'll come back to that later. What about effects of high field MR? So what is a high field MR? Anything more than 70s? Tesla is an ultra high field or UHF MR as it's called now. So the first system was the Tesla system at Ohio in 1998, nearly 22 years back. And the first seven Tesla system with approval as a medical device actually entered the market in 2017, four years back, believe that. So as far as high field MR is concerned, so you need to talk about we need to consider the signal to noise ratio, specific absorption ratio and physiological side effects, right? So this is a proven common to each of these when we're dealing with a very high field magnetic strengths. Physiological effects would include of course transitory effects like business, noisier, elevated T-waves, acoustic noise. And local SARS can differ in heating may result in local side burning. This is the major limitation with the high field. Moving on to contrast agents in MRI. Now these are designed to reduce relaxation times, most even T2. We are basically using post contrast T1 images. And generally based contrast agents is the most commonly used. We can have linear ones or microcyclic, ionic or non-ionic, right? This is a whole list of the brand names, the chemical name and the structures, right? Remember get a butyrol is the only contrast agent approved for use in children less than two years initially. The adverse effects to MR contrast agents includes mild, moderate and severe. The severe would include arrhythmia, diffuse edema and hypoxia and of course contrast patients. And of course nephrogenic systemic fibrolysis. One thing I forgot to mention here that if given a choice we should go in for a macrocyclic non-ionic contrast rather than a linear contrast. We'll see that later. So nephrogenic systemic fibrolysis is typically described in patients with renal insufficiency, right? It is characterized by thickening, induration and tightening of the skin with subcutaneous edema. This is how the skin would look like. In severe cases you can have joint contractures and immobility. So it is more described with non-ionic linear and then ionic linear and then macrocyclic, right? But majority of times with very high doses or multiple doses in the short period of time that too linear contrast agents. So now classification of contrast agent by the American College of Radiology Committee on Drug and Contrast Media and the EMA European Medicine Agency in the US Now three categories are described based on the association with the nephrogenic systemic fibrolysis. We have a group one which have been described as having the maximum effect with the NSF for the nephrogenic systemic fibrolysis. So these are by and large stopped or contraindicated. Group two is the one more commonly recommended which includes multi-hands, prohams, guttural and ghetto-waste. While group three are still newer agents with limited data and limited applications. So these are the European medicine agencies, the EMA band contrast agents in Europe. They are still in use in other parts of the world. But these are the ones, linear ones with far more effects of NSF specifically. So they are not recommended now. These need to be known. I think we all need to be aware of the chokes questionnaire. There are six questions. Even if you don't know the EGFR or the estimated renal function test, or the correct renal function test, you can ask this six questions and all six are nine. 94% of the patient would have a normal serum. So this is one way of doing it in an emergency setting if you do not have access to the lab values and estimated GFR rates. So the ACR guidelines and contrast use specifically in chronic kidney disease. So in patients with EGFR are really less than 30. So group 1s are contraindicated. Group 1 is again contraindicated if it is less than 30 northern dialysis. The first one was in dialysis. And group 2 agents are usually preferred. That is the bottom line as far as the ACR guidelines go if the EGFR is less than 30. Contrast deposition in brain has been now being increasingly reported. These are like dose dependent signal hyperintensity in the tentative nucleus and clover's pallidus on unenhanced scans. And reported in patients with normal renal function actually. This has been reported again with the linear groups ghetto-diamide and ghetto-pentate. Has not been directly linked to adverse health effects but FDA had given a warning in 2017 specifically in children who want to go to repeated MR scans with contrast like oncology patients, human group patients who would require repeated three monthly or six monthly or yearly contrast examinations. So can MR contrast be used in pregnant or lactating mothers? So there are lack of control studies but studies have found increased risk in first trimesters. There's no adverse effects on fetus as of now. And so ACR recommends the group 2 agents, not group 1, group 2 agents with least possible dose with very documented risk benefit analysis and preferably after first semester. Remember in first semester of pregnancy it's not recommended to give contrast. After first semester of pregnancy if the risk benefit analysis has been done then the group 2 agents with least possible dose. Lactating mothers there is no no issue at all. You can use contrast code. What about implants and MRI? So device safety and MRI actually first introduced by STM International in 2005 has been like 16 years now. So as of now the what are the norms is like you have for all implants three different categories have been defined whether they are MR-safe, MR-conditional, MR-unsafe, right? And data on majority of the devices available on www.mrysafety.com. You can just go and have a look. So either your device is going to be MR-safe, go ahead, no issues, it's going to be MR-conditional, they don't do specific conditions of use or MR-unsafe, you cannot use it, right? So appropriately and accordingly the signals have been demarcated in the color code green, yellow and red, right? So these are the different examples of MR-safety as you can see this is green, the IV line says MR-conditional, some pacemakers and MR-unsafe, scalpel or the member talic ones. So MR-conditional, the patients can be scanned with MR-conditional like ECG leads, pulse monitors, cardiac monitors, right? Intercontinental aneurysm clips, well certain types of intercontinental aneurysm clips like those made from martinistic stainless steels that were earlier used. Now these steels, stainless steels are not used nowadays intercontinental clips. So these were clips made later than 1980, do not use this, right? So you can use a plain CT or radiograph to confirm whether a clip is present or not, although the newer ones do not use this, but the older intercontinental aneurysm clips, if they are still there, that is a contraindication. So you need to have a specific information with the original package material, obtain written documentation and considerations should also be given to the static magnetic field strength. On the other hand, cardiac implantable electronic devices including cardiac pacemakers, defibrillators, loop recorders, or temporary transmittance pacing comes in it. These are conditional in use, right? And the heart rhythm society guidelines has approved them. Cardiac pacemakers is MR-conditional. So class one is a strong recommendation that has only context of an institutional workflow. While class two recommendation is MR- non-conditional systems perform MR-i in the absence of fractured epicardial or abundant leads. So this is important, right? So as far as these guidelines, if the device is MR-conditional, go ahead. If it is not, their lead abnormalities do not perform MR. If there are no lead abnormalities, but pacemakers dependent, then you need to proceed with questions still whether you need to keep it on or you would need to remove it and then turn it on again. You might have to call the cardiac guy sometimes for it, right? So as far as cochlear implants are concerned, again the implants made earlier than 2010 are mostly labelled as unsafe. The recent cochlear implants containing an internal magnet have both USFDA and ASTM marketing. If they have manufacturers, they're pretty okay to use. So as you can see there, this is a cochlear implant on a plane radiograph. This is the radio frequency antenna. This is the external speech processor and this is the electrode width. This is the components of your senior radiography. So MR- conditional cochlear implants are there, yes, right? And the head wrap on a splint is often used during MR imaging. And after completion of the examination, this is important for cochlear implants specifically. You remove this splint. External speech processor is again inserted to check the functionality and you can again do a radiograph to confirm the position of the magnet, okay? As far as orthopedic implants are concerned, most that have undergone nailing or plating do not have any significant displacement. So if there's an orthopedic implant which is fixed nicely, right, they are not loose. They can be used in a 1.5 Tesla magnet and granny setting, but they should be properly fixed and are passive. That's the main thing. Implant displacement and radio frequency heating otherwise is the major concern with orthopedic implants. So implants absolutely contraindicated for MR would be cardiac pacemakers with abundant or fractured leads, temporary transvenous pacemaker leads, the temporary ones, okay? Interagonal and resumed clips with martinistic steel as component and cochlear implants manufactured before 2011. Moveable metallic implants or piercings anywhere in the body which are movable. Patients with suspected pellets or shrapnels visit the eye and insulin infusion pumps or drug delivery pumps with metallic components. So we need to be careful about. As far as emergencies in MR room is concerned, our MR suite should be equipped with emergency medical equipment on a crash card, but the response, the medical emergency response should not be conducted in the zone four. You bring the patient outside to a designated area to provide medical care, right? Now MR coenching is a very important term which you must be aware of. Now this is a process where there's a sudden loss of absolute zero of temperature in the magnetic coils so that they cease to be superconducting and become resistive. The quenching causes helium to escape from the crash and bath extremely rapidly. Now this can happen accidentally or in an emergency by activating the quench button. There is a quench button in each MR, right? So if you accidentally press it or in an emergency press it, there is a certain loss of absolute zero of the temperature in the magnetic coils. So what happens the liquid helium which is at minus 269 degrees centigrade boils off to become a gas with a high expansion ratio. So this is vented outside the building via the quench pipe so there is a risk of asphyxiation, frostbite and damaged MR system. So if the pipe fails there may be a build-up of pressure in the MR scanner room itself, right? As seen here. So what to do in the event of a quench? So open the scanner room, evacuate the scanner room safely and oxygen monitoring it from where. So I would like to conclude by saying the proper training of MR personnel working in MR suite is very important and it should really be emphasized and re-emphasized. Familiarity with the missile effect of the ferromagnetic materials should be made aware to all the staff working there. We should try to reduce the caustic noise whenever possible, specifically in units by using ear plugs. Look for radio frequency heating. Communicate well with the patient. Try to minimize sedition issues with pediatric patients and develop or use a good screening questionnaire for contrast implants allergies and pregnancy. Thank you. If there are any questions you can email me or ask me at any time. Thank you so much.