[1] Harbor UCLA Med Ctr, Dept Neurol, Torrance, CA 90509 USA
[2] VA Long Beach Healthcare Syst, Dept Neurol, Long Beach, CA USA
[3] Univ Calif Irvine, Dept Neurol, Irvine, CA 92717 USA
[4] Univ Calif Irvine, Dept Neurosurg, Irvine, CA USA
[5] Univ Calif Irvine, Dept Pathol & Lab Med, Irvine, CA USA