[1] St Rita Med Ctr, Dept Neurosurg, 830 W High St,Suite 390, Lima, OH 45801 USA
[2] Temple Univ, Dept Biol, Coll Sci & Technol, Philadelphia, PA 19122 USA
[3] Temple Univ, Sbarro Hlth Res Org, Philadelphia, PA 19122 USA
[4] Massachusetts Gen Hosp, Dept Neurosurg, Boston, MA 02114 USA
[5] Thomas Jefferson Univ, Dept Neurosurg, Philadelphia, PA 19107 USA
[6] Univ Minnesota, Med Sch, Dept Neurosurg, Minneapolis, MN 55455 USA
[7] Emory Univ, Sch Med, Dept Neurosurg, Atlanta, GA USA