i wasn't able to get a straight answer out of anybody at the radiology department regarding why the second mri was requested, so i've cancelled it. i was specific: do you think you might see a tumour? do you think you might see a lesion? all i could get was "the doctor is requesting a second mri". an appeal to authority is simply not convincing to me.
i have verified at least that the information was sent to the referring doctor, so i will call them on tuesday for further exploration of the issue.
while it is possible that the radiologist was just incompetent with his notes - that he has a good reason that he didn't specify because he's lazy - my reading of the situation is that he's just looking for a way to bill me twice, and that that's actually probably a good sign because it probably at least rules out the tumour.
as mentioned previously, i'm leaning more towards lyme disease at this point. but, i'm going to need to see the scans myself....