Unusual CT features of dermoid cyst in the posterior fossa.

A dermoid cyst of the posterior fossa in a 73-year-old man is reported. The presentation of the cyst was unusual because of the age of the patient, the spontaneously hyperdense aspect of the mass on CT, the partial rim enhancement of the lesion, and the presence of perilesional edema. On pathologic examination, the cyst contained small amount of fat, hairs, necrosis, and small areas of hemorrhage. The amount of hemorrhage found could not explain the spontaneous hyperdensity of the lesion found on CT. The hyperdensity may be related to high protein content of the lesion.

[Apropos of the 18th case of bismuth encephalopathy recognized in Belgium]. / A propos du dix-huitième cas connu d'encéphalopathie au bismuth en Belgique.

The authors present a typical case of bismuth encephalopathy detected in 1982. The patient was given oral insoluble bismuth salts for 20 years. Blood bismuth level was regularly measured (twice a year). No pathologic level was ever noted before she developed the intoxication. Up to now, only few reports are known in Belgium. Measures to prevent this encephalopathy are discussed.

[The large somatosensory evoked responses (author's transl)]. / Les potentiels évoqués somesthésiques géants.

Giant cerebral evoked potentials have been observed in a case of brain stem tumor and in hydrocephaly. The mechanism of the amplitude augmentation has been discussed.