Magnetic resonance images from 197 patients with calcified neurocysticercosis (NCC), 38 with viable NCC and 197 NCC-free healthy rural villagers were evaluated to compare the frequency of hippocampal atrophy/sclerosis (HAS) across these populations. Scheltens' medial temporal atrophy scale was used for hippocampal rating. The median age of the 432 study participants was 46 years (interquartile range, 29-62 years), and 58% were women. Hippocampal atrophy/sclerosis was disclosed in 26.9% patients with calcified NCC, compared with 7.9% in patients with viable NCC and 8.1% in healthy rural villagers. After adjusting for age, gender, and history of epilepsy, hippocampal atrophy/sclerosis was more frequent in patients with calcified NCC than in those with viable cysts (RR, 3.60; 95% CI, 1.18- 0.99; P = 0.025) and healthy rural villagers (RR, 3.43; 95% CI, 1.94-6.06; P < 0.001), suggesting that hippocampal damage develops late in the course of this parasitic disease.