Objective: To investigate the surgical methods and results of enlarged translabyrinthine approach in the removal of large acoustic neuromas.
Method: A large mastoidectomy involved complete exposure of sigmoid sinus, the dura behind the sinus for at least 1 cm, the superior petrosal sinus and the middle fossa dura. The jugular bulb was exposed and pressed downwards if necessary. The internal auditory meatus was skeletonized and uncovered for at least 270 degrees. The debulking of the tumor began inside the anterior and inferior poles in order to find the brainstem and the facial nerve root as early as possible, then the dissection of the nerve was performed medially to laterally. Intraoperative facial nerve monitoring and postoperative CT and MRI were performed in all cases.
Result: Total removal was achieved in all 18 patients with tumors larger than 3 cm (mean size: 4.2 cm). There were no death as well as other complications such as intracranial infection and persistent cerebrospinal fluid leakage. There were no obvious cerebral sequela. The facial nerve was preserved both anatomically and functionally in 14 cases, with Grade I or II in 8 cases, Grade III or IV in 6 cases. Nerve interruption occurred in 4 cases who all had severe facial paralysis or nerve interruption before operation. 16 patients returned to work within 1-3 months.
Conclusion: Total removal of large acoustic neuroma could be accomplished via the translabyrinthine approach, with good result of facial nerve function and minimum incidence of morbidity.