1. Department of Neurosurgery and Spine Surgery, University Hospital Essen, Germany. (A.N.S., L.R., D.S., B.C., A.H., T.F.D., R.J., K.H.W., U.S., P.D.)
2. Institute of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Germany. (Y.L.)
3. Department of Pediatrics, University Hospital Essen, Germany. (S.T., A.D.M., C.D.-S.)
4. Institute for Medical Informatics, Biometry and Epidemiology, University Hospital Essen, Germany. (B.S.)