MR observations on the effects of praziquantel in neurocysticercosis.

Eight patients with neurocysticercosis treated with praziquantel (PZQ) were studied with serial MR imaging to demonstrate the early effects of the drug in brain lesions. Increase in cyst size and appearance of pericystic edema were observed as early as 24 hr, followed by gradual degeneration of the scolex and cyst contents. Cysts showed varied degree of response to the drug and in their rate of disappearance. MRI was found to be a sensitive technique to objectively document early changes in the parasite and patterns of response to the cysticidal drug in brain cysticercosis.