[1] Univ Hosp Tuebingen, Hertie Inst Clin Brain Res, Dept Neurol & Epileptol, Hoppe Seyler Str 3, D-72076 Tubingen, Germany
[2] Ulm Univ, Dept Neurosurg, Albert Einstein Allee 29, D-89081 Ulm, Germany
[3] Univ Med Ctr Rostock, Inst Diagnost & Intervent Radiol, Pediat Radiol & Neuroradiol, Ernst Heydemann Str 6, D-18057 Rostock, Germany