Spontaneous Umbilical Cerebrospinal Fluid Fistula due to Transdermal Dislocation of the Ventriculoperitoneal Distal Shunt Ending – A Case Report - Fleissig, K.; Hattingen, J.; Wilkens, L.; Förster, C.; Gaab, M. R.; Burger, R. (Journal of Neurological Surgery Part A: Central European Neurosurgery, 2013)