When people say Pittsburgh and GK in the same sentence, they are usually talking about the work of Douglas Kondziolka, et. al., particularly the reports that came out in 1997. Here is a link to the web site, with lots of info and background:
http://www.acousticneuroma.neurosurgery.pitt.edu/index.htmlIt is interesting that many of the results were published 10 years ago, and include results for at least 162 patients who were treated 10-15 years earlier at the time of the study - 20-25 years ago now. If they don't yet qualify as long term studies in the minds of some, they should at least count as pretty long term studies.
Stanford has been doing the same with CK since 1999 or so, and has published their results several times - I think 2005 was the last time. The studies are usually done at larger universities, where they have professors who publish, and a large enough hospital to handle a good number of patients. They want me to either come to Stanford for follow up MRIs and hearing tests, or to send them results if I have them done here in Portland. I think most patients are happy to do so, although I'm sure the response drops off the further out from treatment the patients get.
Steve