Calcified cysticerci provoke perilesional edema and seizures.

In cases of cysticercosis, seizures and other symptoms occur in persons with only calcified brain lesions. The presence of perilesional edema has been documented in association with calcified lesions in symptomatic patients, but the frequency of this complication and characteristics of the patients who develop it are not known. Patients in Peru and the United States with neurocysticercosis, documented by positive results of serological testing and with only calcified lesions as shown using computerized tomography, were studied using magnetic resonance imaging. Perilesional edema was observed in slightly more than one-third of the patients, and some patients had frequent, severely disabling episodes. Those with an increased proportion of enhancing calcified lesions were more likely to show perilesional edema. Edema around calcified lesions is common in this population and is associated with seizures and neurological morbidity.