"Full moon" endoscopic sign in intraventricular neurocysticercosis.

Introduction: Despite improvements in sanitation, diagnosis and treatment, neurocysticercosis is still a public health problem in many countries. In symptomatic patients, there is a broad spectrum of clinical manifestations. When cysticerci are lodged in the ventricles or the subarachnoid space, the flow of cerebrospinal fluid can be obstructed and lead to hydrocephalus and intracranial hypertension. The endoscopic view may be useful as a diagnostic tool.

Patients: This report clearly shows a common endoscopic pattern in 4 selected patients with ventricular cysticercosis (2 third ventricle/2 lateral ventricle). The endoscopic view of the cysts in the ventricles resembles a "full moon". This analogy helped to identify the features of cysticerci with intact walls and the vesicular stage, malleable due to its cystic content and having an irregular surface, as evidence of the microscopic structure of the cyst wall in a cysticercus.

Conclusions: This finding is not seen in other intraventricular cysts or tumors that can actually be considered as an additional diagnostic criterion among the definitive findings to establish the diagnosis of cysticercosis, since it involves direct endoscopic visualization of a cysticercus under histopathological demonstration. Additionally, the endoscopic approach can be used as primary treatment for these cases, following the minimally invasive approach principle.