Abstract
As in the case of fenestration operation a postoperative reaction in the labyrinth can set in after stapes mobilization. A transitory cochlear reaction has been demonstrable in 4 out of 50 patients immediately after the mobilization, but the symptoms have subsided after only 2 to 3 days. It seems probable that they are caused by disturbances in the hydrodynamic conditions in the labyrinth brought about by the operative trauma. They do not, however, seem to affect the final result of the operation.