Recurrence and Facial Nerve Function in Relation to the Extent of Resection of Vestibular Schwannoma Surgery.

Kim, Choong Hyo; Seol, Ho Jun; Kim, Chi Heon; Kim, Dong Gyu; Jung, Hee Won

Original Article

Journal of Korean Neurosurgical Society 2004;36(3): 201-205.

Choong Hyo Kim, Ho Jun Seol, Chi Heon Kim, Dong Gyu Kim, Hee Won Jung

¹Department of Neurosurgery, Seoul National University College of Medicine; Clinical Research Institute, Seoul, Korea. hwjung@snu.ac.kr
²Department of Neurosurgery, Kangwon National University College of Medicine, Chuncheon, Korea.

ABSTRACT

OBJECTIVE
The aims of the surgical treatment of vestibular schwannoma are complete removal with preserving facial nerve function. Complete removal, however, carries significant risk of facial nerve palsy. Alternatively with subtotal removal of tumor, recurrence rate was known to be high. The objective of this study was to assess the risk of tumor recurrence and postoperative facial nerve function in relation to the extent of surgical resection. METHODS: From 1990 to 1999, 125 cases of vestibular schwannoma were retrospectively reviewed. The degree of resection was classified as gross total resection (GTR), near total resection (NTR), Subtotal resection (STR). The tumor recurrence or re-growth was determined by the increase in its greatest dimension on follow-up imaging studies. Facial nerve function was graded with the modified House-Brackmann Grade postoperatively. For clinical comparison, these were grouped into the categories: good ; grade 1-2, intermediate or poor; 3-6.
RESULTS
Of the 125 patients, 28(22%) underwent GTR, 37(30%) had NTR, and 60(48%) had STR. The recurrence rate were 3.5% (1 of 28), 7.8% (3 of 37) and 28% (16 of 60) for GTR, NTR and STR. GTR and NTR showed no statistical difference in recurrence rate (P=0.628). However NTR had less recurrence rate than STR (P=0.034). The postoperative good facial nerve function achieved in 22% of GTR, 53% of NTR and 53% of STR. NTR had lower risk of facial nerve palsy than GTR(P=0.028).
CONCLUSION
In treating vestibular schwannoma, NTR had higher facial nerve sparing rate than GTR without significantly increasing the recurrence rate. NTR is a good surgical strategy.

Key Words: Acoustic neuroma; Recurrence; Facial nerve injuries