Extraparenchymal neurocysticercosis can involve which of the following sites?

• A. Subarachnoid space, meninges, ventricles, spine, or eyes
• B. Brain parenchyma
• C. Muscles
• D. Lungs

Answer: (A)

Extraparenchymal neurocysticercosis means cysts located outside brain tissue itself, in spaces related to the CNS or in ocular tissue. The sites involved are the subarachnoid spaces around the brain and spinal cord, the meninges, the brain ventricles where CSF flows, the spine, and the eyes. These locations are within the CSF pathways or visual system, which is why they’re categorized as extraparenchymal rather than within brain parenchyma. Involvement of these spaces can cause symptoms like hydrocephalus, meningitis-like illness, spinal radiculopathy, or vision problems. Muscles and lungs can harbor cysticerci in systemic cysticercosis, but they’re not part of extraparenchymal neurocysticercosis.