Mature Cystic Intracranial Teratoma with Intraventricular Rupture: Case Report and Management of Secondary Hydrocephalus

Background. Intracranial teratomas are rare germ cell tumors, and rupture of a mature teratoma into the ventricular system has been reported only occasionally. There is no established approach to the hydrocephalus that follows rupture. Case presentation. A 40-year-old man had a 1-year history of holocranial headache, followed by cognitive decline over 6 months, gait instability over 2 months, and nausea and vomiting over 3 weeks; visual acuity was 20/50 in both eyes, with papilledema. Magnetic resonance imaging (MRI) showed a 3 × 2 × 1.9 cm heterogeneous midline suprasellar lesion with fibrous and cystic components, loss of signal on fat-suppressed sequences, intraventricular extension, obstructive hydrocephalus, and a fat–fluid level that suggested rupture. Through a bifrontal craniotomy assisted by ultrasonography and neuroendoscopy, we found an ependymal defect connecting the tumor cavity with the ventricles, and turbid, oily cerebrospinal fluid (CSF) with hair and lipid-rich debris. We achieved gross-total resection, irrigated the ventricles, performed an endoscopic third ventriculostomy (ETV), and left an external ventricular drain (EVD) for 14 days. Histology showed a mature cystic teratoma and the wall of a degenerated cysticercus. At 12 months the patient was neurologically stable, without recurrence and without a permanent shunt. Conclusions. Neuroendoscopy confirmed the rupture suggested on MRI and showed the extent of CSF contamination, which led us to combine resection with ventricular lavage, ETV, and temporary drainage.