Metastatic involvement of the eighth cranial nerve: a temporal bone study

ABSTRACT

A total of 251 temporal bones belonging to 130 patients who had malignant disease were revised for evidence of metastatic involvement of the VIIIth nerve within the internal auditory meatus. Twenty-one bones from 14 cases, were recovered, found positive for secondary implication of the VIIIth nerve and included in the study. The pathologic findings of 21 temporal bones with metastatic involvement of the VIIIth nerve are reported and correlated with the clinical history, autopsy findings and pathologic changes in the inner ear. It was concluded that a generalized insight has been developed regarding the magnitude of metastatic [secondary] involvement of the VIIIth cranial nerve which may be more prevalent than realized. Diagnosis of VIIIth nerve involvement by metastatic disease may contribute clues to the prognostic evaluation of the patient's status. Five pattern of implicating the VIIIth nerve by metastatic malignancies within the internal auditory canal are recognized and reported