[1] Cleveland Clin, Dept Neurol Surg, Cleveland, OH USA
[2] Case Western Reserve Univ, Sch Med, Cleveland, OH USA
[3] Cleveland Clin, Cerebrovascular Ctr, Cleveland, OH USA
[4] Cleveland Clin, Neurol Inst, Rosa Ella Burkhardt Brain Tumor & Neurooncol Ctr, Cleveland, OH USA
[5] Cleveland Clin Fdn, Dept Neurol Surg, 9500 Euclid Ave, Cleveland, OH 44195 USA