A Progressive Enlarging Intraparenchymal Pericatheter Cyst and Cerebral Spinal Fluid Edema Following Ommaya Reservoir Placement.

Spread of cerebral spinal fluid (CSF) into the brain parenchyma is a very rare complication of Ommaya reservoir placement and can take form of CSF edema or an intraparenchymal pericatheter cyst. Herein, we described an extremely rare case of a progressive enlarging intraparenchymal pericatheter cyst and CSF edema in a patient with cerebral cysticercosis following Ommaya reservoir placement. A heightened index of suspicion of this rare complication is required to prevent misdiagnosis as a tumor or brain abscess that may lead to unnecessary surgical explorations.