Conservative versus primary surgical treatment of acoustic neuromas:: a comparison of rates of facial nerve and hearing preservation

Objectives: To determine whether patients with small to medium sized acoustic neuromas managed conservatively suffer reduced rates of facial nerve and hearing preservation when compared with patients undergoing primary surgery. Design: An intention-to-treat comparison between patients managed conservatively at first presentation and those managed with primary surgery. Setting: Tertiary referral neurotological centre in Birmingham, UK. Participants: Data were drawn from our database of 487 sporadic acoustic neuromas managed from 1997 to present day. Main outcome measures: Facial nerve status (assessed using the House-Brackmann system) was collated for all conservatively managed patients (n = 167) and compared with that expected when calculated from primarily surgically managed tumours of equivalent size (n = 121). A chi-square test was employed to test the statistical significance of any difference. Hearing preservation (maintenance of AAO-HNS Class) in patients presenting with Class A or B hearing was compared between conservatively managed patients and those with primary surgical management. Results: Observed facial nerve preservation in conservatively managed patients was significantly better (P < 0.001) than expected when calculated from rates of facial nerve preservation in surgically managed patients. Hearing preservation was also significantly more successful in conservatively managed patients (Pearson chi-square: P < 0.000). Conclusions: An initial period of conservative management is a safe and reasonable management policy in all acoustic neuromas up to 2 cm in size at the cerebello-pontine angle. Given that there are no failsafe ways of deciding potential for growth in acoustic neuromas, initial conservative management of these tumours offers superior hearing and facial nerve preservation when compared with primary surgical treatment.