Small acoustic neuroma: observation or treatment ? A review of 207 cases

The management of small acoustic neuromas (AN) whether localized in an intr acanalar position (stage I) or with a small extension of less then 2 cm int o the cerebellopontine angle (stage II) remains tinder debate. Proposed str ategies include surgery, stereotactic irradiation and observation. From 198 7 to 1997, among 343 AN referred to our department, 207 were small (83 stag e I and 124 stage II). Initially, 72 patients were treated conservatively, mainly because of their age (over 60-65) and 132 were operated on. Three pa tients underwent irradiation because of their poor general condition. Signi ficant tumor growth was observed in 15 cases in the conservative treatment group; 14 of these patients underwent secondary surgery and one irradiation . Among the 146 AN operated on (132 initially and 14 secondarily), 142 small AN were operated on via a transpetrosal approach (64 % translabyrinthine, 2 1 % middle-fossa and 15 % retrosigmoid) and 4 AN, which became large tumors during the observation period, were treated through the translabyrinthine approach. No mortality was observed in our series. Postoperative complicati ons included 11 CSF leakages necessitating reoperation (8 %). In 93 % of th e cases, postoperative facial function at one year was good. Hearing preser vation was attempted in 51 selected cases (pure tone average 50 dB, speech discrimination score 100 %) with a 51 % success rate (53% and 48 % through middle-fossa and retrosigmoid approaches respectively).