Clinical course of abducens nerve palsy associated with skull base tumours.

BACKGROUND

The clinical course of abducens nerve palsy associated with skull base tumour is rarely reported. In this study, we examined the post-operative course of abducens nerve palsies associated with various skull base tumours.

METHOD: Between January 2003 and December 2006, 240 patients with various skull base tumours underwent surgery at Kyushu University Hospital. Among them, nine patients presented with abducens nerve palsies (ten nerves) following surgery. The conditions included two pituitary adenomas, two trigeminal schwannomas and five meningiomas. We evaluated the function of the abducens nerves in these patients on admission, at discharge, and periodically in the outpatient clinic.

FINDINGS: Four of the abducens nerve palsies already existed prior to surgery, and six of them developed post-operatively. In the four patients with pituitary adenomas and trigeminal schwannomas, all nerves were anatomically preserved and showed complete recovery of function within 6 months after surgery. In contrast, only two of the six palsies in patients with skull base meningiomas showed complete recovery. In three patients with petro-clival meningiomas, the abducens nerves were completely transected during surgery, and one was reconstructed using fibrin glue. This patient remarkably recovered from the abducens nerve palsy within 2 years.

CONCLUSIONS

The abducens nerve palsies in pituitary adenomas and trigeminal schwannomas showed a better clinical course compared to those in skull base meningiomas. The abducens nerve palsies that occur with skull base meningiomas are less likely to recover. Nevertheless, it is important to preserve the nerves and to perform surgical repair if the nerve is transected.