Hi sissylou
I have a VNS sence 2003 and I have never heard of a test you can,t have, I have had every test under the sun,when you go in for a MRI you just have them turn your VNS off and calibrate the machine down and they can put a apron on you when you lay down its not that hard. they know what to do really they have done this alot just make sure you tell every one in the room about your concerns and they will answer them for you if they can.and PET scans are the same and the spec was the same as well they can do all three with the implate in they just have to turn it off you will find you will need to inform the medical ppl of your device,we have to be in charge of are own health some times no one else will do it for us.I hope this answers your questions to some point take care and the best of luck traci
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