[1] Univ Tennessee, Ctr Hlth Sci, Coll Med, Memphis, TN 38163 USA
[2] Univ Tennessee, Ctr Hlth Sci, Dept Neurosurg, Memphis, TN 38163 USA
[3] Johns Hopkins Univ, Sch Med, Dept Neurosurg, Baltimore, MD 21205 USA
[4] Univ Alabama Birmingham, Sch Med, Dept Neurosurg, Birmingham, AL USA
[5] CHI St Vincent Infirm, Arkansas Neurosci Inst, Little Rock, AR USA
[6] Rhodes Coll, Memphis, TN 38112 USA
[7] Le Bonheur Childrens Hosp, Memphis, TN USA
[8] Univ Michigan, Dept Neurosurg, Ann Arbor, MI 48109 USA
[9] Semmes Murphey, Memphis, TN 38120 USA