The learning curve in vestibular schwannoma surgery.

OBJECTIVE

This study aimed to examine the effect of surgical team experience on facial nerve function and complication rate in vestibular schwannoma surgery.

STUDY

DESIGN

The study design was a retrospective analysis of a case series.

SETTING

The study was conducted at a tertiary referral center.

PATIENTS: One hundred sixty consecutive patients undergoing vestibular schwannoma excision participated.

INTERVENTION: Surgical excision of vestibular schwannoma via a translabyrinthine, middle cranial fossa, suboccipital, or combined approach was performed.

MAIN OUTCOME MEASURES: Facial nerve function (House-Brackmann score) and complication rates including cerebrospinal fluid leak and meningitis compared by groups of 20 patients were measured.

RESULTS

There was a statistically significant improvement in the number of patients achieving a House-Brackmann grade I result between the first 20 patients (35% House-Brackmann grade 1) and the ensuing 7 groups of 20 patients (74% House-Brackmann grade 1) by chi2 analysis. When considering House grades I and II together, there was no statistically significant difference in facial nerve function in the first 20 patients (80%) compared to the last 7 groups of 20 patients (88%) by Tukey's pairwise comparisons (p = 0.245). Mean tumor size was not significantly different in the groups studied (p = 0.54). The total cost of patient care declined over the study period; however, the wide case-to-case variance made it so that this trend was not statistically significant (p = 0.448).

CONCLUSIONS

A learning curve of 20 patients was demonstrated by this study to have been necessary for attaining acceptable standards in the surgical removal of vestibular schwannomas by a new surgical team. The findings of this study may have implications for patient care and surgeon training.