The aim of the present study was to establish the relationship between viab
ility of the hydatid cyst and its ultrasonic appearance (Gharbi classificat
ion). To evaluate cyst viability, the criteria that were reported by the Wo
rld Wealth Organization in 1982 for both the microbiological evaluation of
the cystic fluid and the pathological evaluation of the cyst wall were used
. In this study, the possibility of being viable was high in Type I cysts;
the possibility of being dead was high in Type IV cysts. It is concluded th
at there is a relationship between ultrasonic appearance and the evolution
of hydatid cysts.