[1] Rutgers New Jersey Med Sch, Dept Orthopaed Surg, 140 Bergen St,ACC D1610, Newark, NJ 07103 USA
[2] Rutgers New Jersey Med Sch, Dept Neurol Surg, Newark, NJ 07103 USA
[3] Philadelphia Coll Osteopath Med, Philadelphia, PA USA
[4] Univ Pittsburgh, UPMC Hillman Canc Ctr, Dept Radiat Oncol, Sch Med, Pittsburgh, PA USA
[5] Univ Pittsburgh, Med Ctr, Dept Neurosurg, Pittsburgh, PA USA
[6] Univ Maryland, Sch Med, Baltimore, MD 21201 USA
[7] Harvard Med Sch, Beth Israel Deaconess Med Ctr, Neurosurg Serv, Boston, MA 02115 USA