Intraparenchymal Pericatheter Cyst after Cerebrospinal Fluid Shunt: A Rare Complication with Challenging Diagnosis - Case Presentation and Review of the Literature.

An intraparenchymal pericatheter cyst is a rare complication of ventriculoperitoneal shunt, which is not well described yet. Due to its rarity, lack of characteristic symptoms and radiological features that often mimic brain tumors or abscesses, especially in head computed tomography without contrast can be easily misdiagnosed. We report the case of a 9-year-old girl who was admitted to a peripheral hospital due to severe headaches and vomiting. The child had a history of craniotomy and ventriculoperitoneal shunt for posterior fossa tumor, performed in our department, 4 years earlier. The patient underwent a brain magnetic resonance imaging (MRI) scan and transmitted to our hospital with the diagnosis of brain tumor. However, a closer look at the MRI established the diagnosis of intraparenchymal pericatheter cerebrospinal fluid cyst; hence, the patient underwent shunt revision and cyst drainage. We researched the literature and described 20 reported cases, discussing the pathophysiological mechanisms, the radiological features, and the optimal treatment of this interesting, yet a challenging complication.