ABSTRACT
Cerebral hydatid disease [CHD] is a rare manifestation of echinococcosis but it constitutes a significant fraction of all intracranial mass lesions. In this paper we have reported two children with primary CHD without associated extracranial lesions. Two cases of isolated cerebral hydatid disease are described. They were 7- and 10-year old children referred with focal neurological deficits and intracranial hypertension. Extensive extracranial investigations were negative. The literature concerning isolated cerebral hydatid disease is reviewed, and possible mechanisms by which the disease can be limited to brain, are discussed. Isolated CHD can occur with different mechanisms. Lack of effective immune system in the brain, the special architecture of brain tissue permitting rapid growth of cyst, patent ductus arteriosus, and patent foramen ovale, have been the proposed factors, but none of them has been proved yet