1. School of Medicine West Virginia University Charleston West VirginiaU.S.A.
2. Department of Anesthesiology and Perioperative Medicine Division of Pain Medicine Mayo Clinic Rochester MinnesotaU.S.A.
3. Department of Anesthesiology University of Pittsburgh School of Medicine Pittsburgh PennsylvaniaU.S.A.
4. The Spine and Nerve Center of the Virginias Charleston West Virginia U.S.A.