Interesting. I had no idea of the this specific side effect of radiation until my RO brought up the topic in Sept 08, telling me what was planned for during my next check up. He told me he was going to do a carotid ultasound in December 08. He does one after 1 yr and after 3 yrs as a std test. He told me that a certain % of time radiation will cause problems with blockage issues( I can't remember the %). I am not sure if all patients at Duke do this test or just his patients but he was very insistant I do the test and it is part of the scheduled check up procedure. He said now it is part of the "Gold Standard". Thankfully all was normal