I don't know for sure, but I'm sure they will do an MRI. If there was a lot of swelling, they used to have to wait a few days before the MRI to let the swelling go down, but I'm not sure if technology has made that a mute point now. Once they have the MRI done, they will most likely have to have someone read it and confirm or deny. Probably a day or two at the earliest - a week at the latest. Just my guess however.