Cystic acoustic neuromas. Results of translabyrinthine surgery.

Objective: This study was designed to investigate the surgical outcome of translabyrinthine surgery of cystic acoustic neuromas.
Design: Prospective registration of audiovestibular, otoneurologic, and neuroradiologic data of all patients operated on for cystic neuromas in the period 1976 to 1992. The diagnosis was proposed by neuroradiologic investigation, confirmed at surgery, and verified histologically. Clinical follow-up was performed 1 year after surgery.
Setting: The study included all patients with cystic acoustic neuromas from the entire country, referred to the centralized otoneurosurgical team in the Department of Otorhinolaryngology-Head and Neck Surgery, Gentofte University Hospital, and Department of Neurosurgery, Rigshospitalet, University of Copenhagen, Denmark.
Patients: The study included 23 patients (11 female and 12 male). Ages ranged between 23 and 77 years with a median of 51.2 years.
Main Outcome: Our hypothesis suggested that surgical outcome of cystic acoustic neuromas was poorer compared with noncystic acoustic neuromas of matching size. The results of this study seem to confirm the hypothesis.
Results: The results are rather poor compared with results achieved in surgery of noncystic tumors of matching size, particularly the poor postoperative facial nerve function.
Conclusions: Even though the operation for a cystic acoustic neuroma may appear to be easier and faster than the operation for a solid tumor, there is a high risk for accidental lesion of the facial nerve, in spite of using facial nerve monitoring. Rapid symptomatic worsening may occur due to sudden expansion of cystic elements and, therefore, a wait-and-see policy should not be applied to patients with cystic tumors.