Does choice of hearing selection criterion and reporting criteria affect the hearing preservation rate in vestibular schwannoma surgery?

With increasing refinement in the surgery of vestibular schwannoma the aims of complete tumor removal and facial nerve preservation have been largely fulfilled. However, the reputation of and place for hearing-preservation surgery still remain uncertain. A major part of this uncertainty is the result of difficulties in interpretation of the various reported results of hearing-preservation surgery. Meaningful comparison between series is difficult because of the varied number of postoperative reporting criteria commonly in use today. Although it is acknowledged that the postoperative reporting criteria affect the hearing-preservation rates, what is not readily appreciated is that preoperative selection criteria for hearing-preservation cases can also significantly affect the success rate of hearing-preservation acoustic neuroma surgery. This article models the many possible outcomes of hearing-preservation schwannoma surgery by use of the previously reported Cambridge series as an illustrative example. With these models some understanding can be gained of the effect of choosing various preoperative and postoperative hearing criteria on the overall hearing-preservation success rate.