that might help you? Depends on where you live....

http://health.usnews.com/sections/health/best-hospitals

I will note that when I used their lists 4 years ago the ratings and the hospitals were different...so there are a LOT of top notch hospitals not on these lists that are quite capable of assessing your issues.

If you are in a metropolitan area with more than one university or college medical teaching hospital...then go check out the doctors on their websites...Find one, or several who might be useful and appear to know some aspect in-depth of an issue or two or more of your problems.
Asking not only your GP for references, but every other doc you go to can be very useful as well. Ironically, my podiatrist was one who put out some names that other docs had mentioned [I've been going to him for 20+ years and HE was the one that urged me to seek a 2nd opinion when Neuro #1 was lacking- saved my life in the end?] It never, ever hurts to ask! Asking is free, not asking could have big consequences.

I will warn you that navigating hospital websites are either easy or hard... Once you find a name ornames you mite like...then just web up the docs' names and see what papers, associations or charitable works they do in the area... In my region, a area monthly magazine publishes every other year a feature on 'Top Docs' in the area...compiled by a survey of other docs as to who they would use if they needed a specialist in X or Y area.....but, I'm in a metro area...

Sure hope this helps! I do wish I could be more specific? But that's going to have to be up to you, I guess. Best of hunting - j