The differential diagnosis between pr imary and secondary tr igeminal neuralgia often has considerable practical importance because of its therapeutic implications. However , in cases in which there is a known etiological agent, a secondary neuralgia may simulate clinically a pr imary form of this condition. Such event occurred in our ~ cases, and in itself consti tutes one of the reasons for this report. I n the cases under discussion, prosopalgias with the characteristics of a pr imary tr igeminal neuralgia were caused by cysticcrci located in the cavum meckclii. To our knowledge tile medical l i terature does not record any previous report on cysticercosis of the cavum meckelii. A bibliographical survey was done in the current indices, and several original articles on neurocysticercosis were reviewed, covering a total of 1,190 cases (clinical observations, clinicopathological or pathological reports only), and no references were found on paroxysmal tr igeminal neuralgia not associated with other focal neurological manifestations.
