An unusual complication of stapes surgery: profuse bleeding from the anteriorly located sigmoid sinus.

Major bleeding during stapes surgery is a rare condition. The anterior course of the sigmoid sinus is comparatively common in contracted mastoid bones, but rare in good pneumatized temporal bones. We report a case of an unusual anterior course of the vertical segment of the sigmoid sinus, which led to profuse bleeding during a stapedotomy operation. The 34-year-old female patient presented with conductive-type hearing loss in the right ear. During the operation, the unintentional sliding movement of a blunt curette caused injury to the anteriorly positioned sigmoid sinus, which was separated from the posterior wall of the external auditory canal by an extremely thin shell of bone. Profuse bleeding from the sigmoid sinus was controlled by pushing the middle part of the oxidised regenerated cellulose inside the lumen, without compromising the sinus flow. After bleeding was restrained, the stapedotomy operation was completed successfully. During the 1-year follow-up, there was neither an air-bone gap nor a sensorineural hearing loss in pure tone audiogram.