[1] HARVARD UNIV, MED SCH, BOSTON, MA USA
[2] UNIV HOSP, RADIOL INST, DEPT RADIOL, ANGIOG UNIT, GENEVA, SWITZERLAND
[3] LARIBOISIERE HOSP, DEPT NEURORADIOL, NEUROSURG SERV, PARIS, FRANCE
[4] UNIV HOSP GENEVA, DEPT NEUROL, NEUROSURG SERV, GENEVA, SWITZERLAND
[5] UNIV HOSP GENEVA, DEPT SURG, DIV ORTHOPAEDICS, GENEVA, SWITZERLAND
[6] VET ADM HOSP, SPINAL CORD INJURY SERV, 1400 VET FOREIGN WARS PKWY, W ROXBURY, MA 02132 USA