Which Neurocysticercosis type develops when cysticerci are inside brain tissue?

• A. Parenchymal
• B. Extraparenchymal
• C. Subarachnoid
• D. Ventricular

Answer: (A)

Parenchymal involvement means the cysticerci are embedded in the brain tissue itself, the brain parenchyma. When the parasite resides in the tissue, this form is called parenchymal neurocysticercosis. The tissue location irritates the cortex and surrounding white matter, so seizures and focal neurologic deficits are common clinical presentations, and imaging typically shows cysts within the brain matter that may progress to ring enhancement and eventually calcifications as the parasite degenses. In contrast, cysts located in CSF spaces—such as the subarachnoid space or the ventricles—fall under extraparenchymal forms and can block CSF flow, leading to hydrocephalus or meningitis-like symptoms. So cysticerci inside brain tissue are classified as parenchymal neurocysticercosis.