title: Percutaneous evacuation (PEVAC) of multivesicular echinococcal cysts with or without cystobiliary fistulas which contain non-drainable material: first results of a modified PAIR method.
abstract: 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.
  
  
  OBJECTIVE
  To evaluate a modified PAIR method for percutaneous treatment of multivesicular echinococcal cysts with or without cystobiliary fistulas which contain non-drainable material.
  
  
  METHODS
  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).
  
  
  CONCLUSIONS
  PEVAC is a safe and effective method for percutaneous treatment of multivesicular echinococcal cysts with or without cystobiliary fistulas which contain non-drainable material.
authors.affiliation: Department of Infectious Diseases, Tropical Medicine, and AIDS, Academic Medical Centre, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands. h.g.schipper@amc.uva.nl
authors.forename: H G
authors.initials: HG
authors.lastname: Schipper
authors.forename: J S
authors.initials: JS
authors.lastname: Laméris
authors.forename: O M
authors.initials: OM
authors.lastname: van Delden
authors.forename: E A
authors.initials: EA
authors.lastname: Rauws
authors.forename: P A
authors.initials: PA
authors.lastname: Kager
mesh_terms: D000328:Adult; D000818:Animals; D000909:Antibodies, Helminth / Q000097:blood; D001658:Biliary Fistula / Q000000981:diagnostic imaging / Q000209:etiology / Q000601:surgery*; D004444:Echinococcosis, Hepatic / Q000150:complications / Q000000981:diagnostic imaging / Q000601:surgery*; D004446:Echinococcus / Q000276:immunology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D013396:Suction; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D018084:Ultrasonography, Interventional
chemical_list: D000909:Antibodies, Helminth; D007074:Immunoglobulin G