Abstract
BACKGROUND: Hydatidosis is a parasitic disease caused by the larvae of Echinococcus granulosus, typically acquired through ingestion of contaminated food. While hydatid cysts commonly develop in the liver and the lungs, the central nervous system is rarely affected, and the cyst predominantly develops within the cerebral parenchyma. However, the ventricular system involvement remains extremely rare. Among the cases of intraventricular hydatid cysts, the lateral ventricles are the mostly affected, while the involvement of the third ventricle remains exceedingly rare, with only five cases previously reported in the literature. CASE PRESENTATION: A 4-year-old Syrian female presented to the neurology department with acute right-eye strabismus, headache, and vomiting for 2 weeks. Ophthalmic examination identified papilledema involving the right eye, while radiological imaging identified a spherical cystic mass in the third ventricle, at the foramen of Monro, leading to right lateral ventricle hydrocephalus. Therefore, the strabismus was likely due to 6th cranial nerve palsy, caused by the increased intracranial pressure. The patient underwent neuroendoscopic cyst excision via the transventicular transforaminal approach. Histopathological examination corroborated the diagnosis of a hydatid cyst. Postoperative management included prolonged albendazole therapy, and follow-up imaging showed no recurrence (refer to Graphical Abstract). CONCLUSION: Hydatid cysts should be considered in the differential diagnosis of intraventricular cystic lesions, although extremely rare. Further studies are necessary to guide standardized protocols for these unusual neurological entities. The surgical intervention is precision-demanding and relies on the neurosurgeon's expertise to prevent intraoperative complications. Histopathological confirmation remains essential for diagnosis in cases of cerebral hydatid cysts.