Gigantic intracranial mass of hydatid cyst.

Abstract

traumatic, or spontaneous rupture ofan existing primary cyst in the brain[15, 19, 22, 25]. In very rare cases,spontaneous or surgical rupture of acyst located in the left ventricle ofthe heart or in one of the great ves-sels may also cause multiple second-ary hydatid cysts in target organs, in-cluding the neural structures [2, 3,29]. Primary cysts, unlike the sec-ondary type, are generally, but notalways, fertile [1, 7, 18, 27].As no extraneural hydatidosis wasdetected, the reported case can easilybe categorized as a “primary multi-ple cerebral hydatid cyst,” which isdefinitely a very rare entity. A verylimited number of patients have beenreported in this category so far, andmost of them have been in the pedi-atric age group [4, 5, 8, 12, 14, 24,27]. A recent report from IstanbulUniversity Istanbul School of Medi-cine Department of Neurosurgerydeals with the long-term range(8–45 years) follow-up of pediatricintracranial hydatidosis: only 1 pa-tient out of 30 in whom this condi-tion was documented was reported tohave multiple primary intracranialhydatid cysts, for an incidence of3.3% [20]. This 7-year-old boy had afatal outcome after four operations in2 years for removal of more than 18hydatid cysts, including intraventric-ular cysts, either by hydatid birth orby the PAIR (puncture, aspiration, ir-rigation, resection) technique. Hewas the only patient in the serieswho required a ventriculoperitonealshunt as the fifth surgical procedure[20]. Cataltepe et al., in Ankara, intheir review of the Hacettepe series,reported 2 cases of primary multipleintracranial hydatid cysts in a total of120 patients, 76% of whom were un-der 15 years of age. The incidence ofprimary multiple intracranial hydatidcysts in their combined series ofadult and pediatric patients was1.7% [9].Perhaps a more likely pathogene-sis in the case reported by Ozkan etal. is the rupture of a viable primarycyst of the brain following a trivialtrauma, leading to secondary hyda-tid cysts [6, 13, 28]. Even thoughthere is no record of such a sequenceof events in the history, the appear-ance of the cysts “as they are closelygrouped and flattened one againstthe other in a single, large nidus,” asin the case reported by Nurchi et al.,provides strong support for this the-ory [18]. Besides the remarkablesimilarity in radiological character-istics, the numerous hydatid cystsextracted in these two pediatric pa-tients also imply the relevance ofthis scenario. Nurchi et al.’s hypoth-esis was that the multiplicity hadmost probably resulted from a fortu-itous tear of the primary cyst, whichhad a superficial location – verysimilar to that of the cyst in Ozkanet al.’s case, which is didacticallydocumented in axial and sagittal MRimages [18, 23].