Acoustic neuroma management: an evidence-based medicine approach

Partisan claims supporting the use of microsurgical resection, radiologic surveillance, and radiosurgery in acoustic neuroma management appear widely in the published literature. However, the strength of the evidence supporting these claims has not been assessed, and the management of acoustic tumors continues to be controversial. The English-language medical literature for the past 23 years was searched for articles dealing with outcomes after acoustic neuroma management. The quality of evidence in each article was classified according to the categories of evidence as defined by a standard appraisal instrument for clinical guidelines. The search produced 111 articles reporting outcomes after acoustic neuroma management. From the 111 studies, 78 (70.3%) concerned surgery, 20 (18%) concerned radiosurgery, 9 (8.1%) concerned radiologic surveillance, and 4 (3.6%) compared different methods of management. From these studies, 95 (85.6%) represented Type III evidence, 6 (5.4%) represented Type IV evidence, and in 10 (9%) a clear-cut definition between Type III and Type IV could not be made. No study was supported by Type I or Type II evidence. The evidence supporting the various methods of acoustic neuroma management is of low quality (Type III or Type IV evidence). Well-designed comparisons between treatment methods do not exist, and therefore claims by clinicians favoring a particular treatment are unfounded. Better quality of evidence from large, well-designed, randomized clinical trials should now be undertaken at the points of clinical equipoise to address the true merits of each modality of acoustic neuroma management.