Hydatid cysts of the brainstem. Two case reports

Cerebral hydatid cysts represent 2-3 % of all ina acranial masses in endemi c countries. Its incidence in posterior fossa is very rare. We report two c ases of brainstem location. Clinically, the lesion exhibited signs of brain stem tumor In two patients, CT scan showed a hypodense lesion. There was no enhancement after contrast administration. One patient was explored by MRI ; on precontrast images, the lesion appeared homogeneous with hyposignal in tensity and smooth limits. T2 weighted MRI and post contrast examination co nfirmed the cyst nature of the lesion. Surgery was performed in the two pat ients. The cyst was first aspirated and its membrane was then removed. Post operatively, one patient died, the other one is still alive but severely a ffected two years later CT scan showed total disappearance of the cyst. The clinical presentation, radiological findings and surgical procedures are d iscussed.