This approach provides the shortest, most direct route to the CPA. Cerebellar retraction is minimized and the lateral end of the facial nerve is clearly visualized. William House popularized this approach, and we advocate its use in patients with hearing loss and in virtually all patients with large neuromas.
The patient is placed supine with the head turned 70° away from the side of the lesion. The head is flexed, but the chin must remain clear of the contralateral clavicle. The head is tilted so the malar is uppermost. A sandbag is placed beneath the ipsilateral shoulder. The thigh is also prepared to enable fascia lata and fat to be harvested in preparation for wound closure. We use a "hockey stick" incision, curving from just above the posterior-superior aspect of the auricle, descending to a point 1 cm behind and below the mastoid tip. Careful attention is given to opening the scalp in two layers. The periosteum is then reflected anteriorly, exposing the posterior aspect of the external auditory canal and the spine of Henle. Care must be taken not to perforate the skin of the canal during placement of the self-retaining retractor. The temporal bone is then drilled in a systematic fashion to provide a corridor of access to the CPA.
Drilling of the temporal bone is performed in four phases:
• Extended mastoidectomy with exposure of the facial nerve.
• Removal of the semicircular canals.
• Exposure of the bony internal auditory canal. To improve access the jugular bulb can be uncovered and retracted inferi-orly.
• Removal of bone around the lateral 270° of the canal.
The dura is then opened longitudinally in the inferior half of the internal auditory canal. The canalicular portion of the tumor is readily evident and the facial nerve identified. The posterior fossa dura is then opened in continuity with the already exposed internal auditory canal, increasing access into the CPA.
The tumor usually displaces the facial nerve anteriorly. This relationship needs to be clarified during resection of the tumor. The superior and inferior poles of the tumor are sequentially inspected, enabling the lateral aspect of the brainstem to be identified. Care must be taken
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