Peter Attia· MD
really has to do with the amount of energy that's being absorbed so what we're doing with the electromagnetic field means you're actually putting in radio frequency right and that radio frequency is always also coming out and that radio frequency is the same thing as a cell phone would get that's called SAR or a specific absorption ratio and the hydrogen ions are basically moving around and that's basically effectively heating you up so it's not quite like a microwave but you can actually think about it as a microwave the wavelength is exactly very similar to an AM radio and so your cell phone is typically far more powerful so as an example I went and did the calculation a while ago on how much SAR we're actually putting into a whole body printable scan and it's equivalent to talking on a cell phone for about four hours interesting but it concentrates it across your whole body right yeah it's funny every time I get an MRI or a whole body the first 30 minutes I'm like it's not so bad and then the last 10 minutes I'm like get me out of here right and we've actually done it that way on purpose because we kind of know that the way we kind of run our sequences or filters together is that we actually kind of want to make get as much information such as yeah you do the head first and that's not nearly as much as doing the abdomen and thighs or probably wear a ton of that heat kissed generated right and is sort of knees to abdomen right and so when you look at basically the overall blood flow which is what's cool is your body well the brain takes 20% of your cardiac output so it's basically like this big cool it's this big heat sink it just cools everything away whereas when you get down and lowered to the legs which you're all muscle it's gonna heat that up and so that's why we figure out how to orient these and what organization to make what plan of sequence is to make it not as uncomfortable commercially what's the best off-the-shelf scanner that could come close to producing the resolution you're producing which is it fully isotropic it's isotropic in the brain but in the rest of the body we're actually doing more conventional clinical images tell us what I said tropic is I'm sorry I should have clarified that sure so what isotropic basically means is that it more bassy slicing you in cubes so a one by one by one millimeter cube for example and the power of actually doing that one by one by one is that you can now look at things again in three dimensions in any direction you want the detail and resolution is perfect and so that's what isotropic means whereas MRI typically can't be done isotropic just because of time you want to cover as much as possible but you want what we call in-plane resolution which is how you orient the first gradient to have the highest amount of detail and