[1] Univ Utah, Dept Biomed Engn, Salt Lake City, UT 84112 USA
[2] Univ Utah, Dept Neurosurg, Salt Lake City, UT 84112 USA
[3] Univ Utah, Interdept Program Neurosci, Salt Lake City, UT USA
[4] Univ Utah, Dept Neurol, Salt Lake City, UT USA
[5] George E Wahlen Dept Vet Affairs Med Ctr, Salt Lake City, UT USA
[6] Univ Utah, Dept Radiol & Imaging Sci, Salt Lake City, UT USA
[7] Harvard Med Sch, Brigham & Womens Hosp, Dept Neurosurg, Boston, MA USA