Intramedullary epidermoid cyst in the brain stem: case report.

BACKGROUND

The incidence of intracranial epidermoid cysts is between 0.2% to 1.8% of all brain tumors. They usually occur in the cerebellopontine angle or parasellar region. Intramedullary epidermoid cyst is rare and only nine cases have been previously reported.

METHODS

A 69-year-old woman had progressive left hemiparesis for 2 years. Computed tomography scanning and magnetic resonance imaging (MRI) revealed that there was a cystic tumor in the pons that was compressing the brain stem. A part of the tumor cyst wall and the content of the cyst were surgically removed by right subtemporal transtentorial approach. The histologic diagnosis was epidermoid cyst. After the surgery, the left hemiparesis was improved and there was no sign of the tumor growth by MRI.

CONCLUSION

The outcome of the previous cases with radical tumor resection was poor compared with the present case in which only a part of the cyst wall and the content were removed. Therefore, radical removal of the whole tumor may not be necessary for intramedullary epidermoid cyst of the brain stem.