Sixteen hydatid liver cysts in 14 patients were treated with a percutaneous double puncture-aspiration-injection (D-PAI) technique with alcohol used as the scolecidal agent. With ultrasound guidance, fine-needle drainage of cysts was performed, and 95% sterile alcohol was injected and left in situ to partly refill the cystic cavities. The same procedure, without reaspiration of the injected alcohol, was performed 3 days later. Viability of scoleces was assessed at each aspiration. Benzoimidazolic drugs were administered 1 week before and 3 weeks after the procedure, to reduce the risk of seeding scoleces. Follow-up ranged from 8 to 28 months (mean, 14 months). Six cysts disappeared within 40-75 days of completion of D-PAI. In the other patients, smaller liquid areas or hypo- or hyperechoic solid masses were observed. Anaphylactoid reactions did not occur. In one patient, a biliary fistula developed after the first aspiration; the second ethanol injection was postponed until 6 months later but was effective. Viable scoleces were found at the second aspiration in only two patients whose hepatic liver cysts completely healed. Serologic titers substantially decreased in seven cases and became negative in two.