[1] Millennium Pain Ctr, 1015 S Mercer Ave, Bloomington, IL 61701 USA
[2] Univ Illinois, Coll Med, Dept Surg, Champaign, IL 61820 USA
[3] Illinois State Univ, Dept Biol Sci, Normal, IL 61761 USA
[4] Illinois Wesleyan Univ, Bloomington, IL 61701 USA
[5] Univ Utah, Dept Neurol, Salt Lake City, UT USA
[6] Johns Hopkins Univ Hosp, Div Vasc & Intervent Radiol, Baltimore, MD 21287 USA