Abstract
We present the case of a 1-year-old girl with persistent vomiting who was found to have a disproportionately large immature teratoma in the third ventricle. Magnetic resonance imaging demonstrated a heterogeneous intracranial mass in the third ventricle, with a compressed left cerebral hemisphere and hydrocephalus. Bifrontal craniotomy via a transchiasmatic approach achieved total resection of the tumor. No significant neurologic deficit was seen except for double vision and disturbances in eye movement. Third ventricle immature teratoma, although extremely rare, may present as a suprasellar mass lesion and hydrocephalus. The prognosis after gross total resection is favorable; however, radiotherapy is usually postponed until 36 to 48 months of age in order to avoid complications such as stunted growth, endocrine disturbances and neuropsychologic problems.