Percutaneous evacuation (PEVAC) of multivesicular echinococcal cysts with or without cystobiliary fistulas which contain non-drainable material: first results of a modified PAIR method.

BACKGROUND Surgery is the treatment of choice in echinococcal cysts with cystobiliary fistulas. PAIR (puncture, aspiration, injection, and reaspiration of scolecidals) is contraindicated in these cases. AIM To evaluate a modified PAIR method for percutaneous treatment of multivesicular echinococcal cysts with or without cystobiliary fistulas which contain non-drainable material. PATIENTS Twelve patients were treated: 10 patients with multivesicular cysts which contained non-drainable material and were complicated by spontaneous intrabiliary rupture, secondary cystobiliary fistulas, cyst infection, or obstructed portal or hepatic veins; and two patients with large univesicular cysts and a ruptured laminated membrane, one obstructing the portal and hepatic veins and one a suspected cystobiliary fistula. METHODS The methods used, termed PEVAC (percutaneous evacuation of cyst content), involved the following steps: ultrasound guided cyst puncture and aspiration of cyst fluid to release intracystic pressure and thereby to avoid leakage; insertion of a large bore catheter; aspiration and evacuation of daughter cysts and endocyst by injection and reaspiration of isotonic saline; cystography; injection of scolecidals only if no cystobiliary fistula was present; external drainage of cystobiliary fistulas combined with endoprosthesis or sphincterotomy; catheter removal after complete cyst collapse and closure of the cystobiliary fistula. RESULTS In all 12 patients initial cyst size was 13.1 (6-20) cm (mean (range)). At follow up 17.9 (4-30) months after PEVAC, seven cysts had disappeared and five cysts had decreased to 2.4 (1-4) cm (p=0.002). In eight patients with multivesicular cysts, a cystobiliary fistula, and infection, cyst size was 12.5 (6-20) cm, catheter time 72.3 (28-128) days, and hospital stay 38.1 (20-55) days. At 17.3 (4-28) months of follow up, six cysts had disappeared and in two cysts residual size was 1 and 2.9 cm, respectively (p=0.012). In four patients without a cystobiliary fistula, cyst size was 14.4 (12.7-16) cm, catheter time 8.8 (3-13) days, and hospital stay 11.5 (8-14) days. At 19.3 (9-30) months of follow up, one cyst had disappeared and three cysts were 85 (69-94)% smaller (2.2 (1-4) cm) (p=0.068). CONCLUSION PEVAC is a safe and effective method for percutaneous treatment of multivesicular echinococcal cysts with or without cystobiliary fistulas which contain non-drainable material.