[1] MED ACAD LUBLIN,DEPT NEUROSURG,PL-20081 LUBLIN,POLAND
[2] VIRGINIA COMMONWEALTH UNIV,MED COLL VIRGINIA,DEPT ANAT,RICHMOND,VA 23298
[3] VIRGINIA COMMONWEALTH UNIV,MED COLL VIRGINIA,DEPT ANESTHESIOL,RICHMOND,VA 23298
[4] WAKE FOREST UNIV,BOWMAN GRAY SCH MED,DEPT ANESTHESIOL,WINSTON SALEM,NC 27103
[5] UNIV CALIF LOS ANGELES,SCH MED,DEPT NEUROSURG,LOS ANGELES,CA 90024