En Bloc Resection of the Temporal Bone for Middle Ear Carcinoma Extending to the Cranial Base.

En bloc resection of the temporal bone for squamous cell carcinoma of the middle ear was performed by the postauricular transtemporal and retromastoid approaches. The patient was a 70-year-old woman whose tumor extended to the middle and posterior cranial fossae. Temporal and retromastoid craniotomies were carried out, then the temporal dura and the cerebellar dura, and the transverse and sigmoid sinuses were exposed. The temporal dura and the cerebellar dura were opened, and the transverse sinus was ligated at the junction with the sigmoid sinus. After that, the tentorial dura was incised, the incision extending anteriorly to the middle cranial fossa and transecting the superior petrosal sinus. Consequently, a wide view into the middle and the posterior cranial fossae was obtained. In the posterior fossa, cranial nerves VII and VIII were divided. On the other hand, nerves IX, X and XI were preserved at the dural incision on the posterior surface of the temporal bone. Subsequently, in the area of the carotid canal, the temporal bone was drilled toward the medial side of the internal auditory canal and also posteriorly down to the jugular bulb. At this stage, the temporal bone and the soft tissue attachments, such as the middle and posterior cranial fossa dura, and the sigmoid sinus, were separated from the pyramidal apex and the clivus. The dural defect was repaired with a free pericranial graft. A rectus abdominis muscle flap was transferred to reconstruct the defect of the skull base resulting from the temporal bone resection. Postoperative complications like CSF leakage, meningitis and lower cranial nerve damage, were not seen after the treatment. The patient has shown no evidence of recurrence for the 28 months since the surgical treatment, and has not complained of any problems with swallowing or conducting conversations in daily life. With the contribution of recent developments in skull base and reconstruction surgery, more aggressive en bloc resection of the temporal bone can be carried out on patients with advanced middle ear carcinoma. These developments will also make it possible for patients whose prognosis was previously thought to be poor to have a chance for a cure.