I got strange looks from every staff member I asked about the Sculpture Garden. Finally an old-timer said "Oh yeah, they did have some pieces out there years ago, but they all got moved and scattered around for the construction". There were a few odd pieces here and there about the grounds, but odd is the operative word-the 4 pieces I found (dodging traffic and commuters all the while) were all quite embarassing-shoddy work that would get the artist a failing grade in any undergraduate sculpture class. If these people do have world class sculptures anywhere, they are keeping them well hidden!
Stay away! (Unless you are sick-the hospital itself is top-notch).