It will likely be necessary to remove the topcase from the computer using the iFixit guide, and temporarily remove the drive from the computer. With the drive removed, you will have a much better view of the opening to the drive, and using a pair of tweezers you should be able to clamp onto one disc at a time and pull them out. It's possible the drive is still working, so I would put it back in place and test it without screwing the computer back together (in case you have to replace the drive).