[Unsuccessful duraplasty technique or persisting/recanalized Sternberg's canal?].

Spontaneous rhinoliquorrhea with or without meningo-encephaloceles in the region of the sphenoid sinus occurs very infrequently. It is not uncommon that the attempt of transnasal endoscopic duraplasty in this region leads to recurrence of the CSF leak. The existence of a lateral craniopharyngeal canal can be a possible explanation for these failures.Retrospective analysis of 23 patients with rhinoliquorrhea of different pathogenesis in the region of the frontal and central skull base that were treated with transnasal, video-endoscopic surgical procedures in our department between 2006 and 2011.2 of 23 patients with proven rhinoliquorrhea following a transnasal video endoscopic duraplasty procedure showed a recurrence of the CSF leak. The computertomographic analysis with respect to the current literature indicated the presence of a craniopharyngeal canal at the lateral side of the sphenoid sinus. This canal is also known in the literature as Sternberg's canal. In contrast to the other 21 treated cases there were no planar skull base defects of different pathogenesis in these 2 cases, but a ontogenetically bony canal. The canal can reopen spontaneously or due to an external mechanical impact.The closure of this bony canal requires a modified surgical procedure such as sufficient padding of the bony canal and its sealing by a vascularized pedicle flap in contrast to the ordinary planar bony skull base defects.