How to detect if a specific version of vcredist_x86.exe has already been installed?

Question

I created an installer that run vcredist_x86.exe (version 9.0.x.x) as part of the installation. Before installing it however I would like to know if it's already in the user's system. I basically need to detect not only that the DLLs are present but that they have the right version number. Is there any reliable way to do that?

I'm using NSIS but any solution would be welcome.