title: Laparoscopic visualization and dissection of retroperitoneal lymph nodes after patent blue dye injection: a pilot study.
abstract: OBJECTIVE
  Retroperitoneal lymph node dissection (RPLND) for testicular cancer is an important treatment modality for patients with stage I or IIA disease. Several urologists have previously reported the feasibility and usefulness of laparoscopic RPLND for such patients. The aim of this experimental pilot-feasibility study was to investigate whether visualization of retroperitoneal lymph nodes with patent blue violet (PBV) dye application is a feasible and an effective method during laparoscopic RPLND in a pig model.
  
  
  METHODS
  Four 12-month-old white male pigs were included in the study. After PBV dye injection into the spermatic funicular and intratesticular parenchyma, the color changes in the retroperitoneal region were examined during transperitoneal laparoscopic visualization of the retroperitoneum. The time interval between the injection and the staining of lymphatic structures was measured for each intervention. Blue-stained retroperitoneal nodal tissues were dissected and removed by the laparoscopic approach and histologic examination was performed.
  
  
  RESULTS
  After PBV dye injection, intense staining of the ipsilateral retroperitoneal lymphatic vessels and nodes was seen. Distribution of the PBV and the color changes of the retroperitoneal lymphatic structures were examined under laparoscopic vision in all pigs. All blue-stained retroperitoneal nodular tissues were removed laparoscopically and examined histologically. Histopathologic examination noted all specimens as lymph nodes with no toxic effects of PBV dye.
  
  
  CONCLUSIONS
  We demonstrated that spermatic funicular injection of PVB dye is an effective and accurate method for retroperitoneal lymph node visualization in pigs. The use of this technique in combination with a laparoscopic approach makes RPLND easier and more effective.
authors.affiliation: Department of Urology, Gülhane Military Medical Academy, Ankara, Turkey.
authors.forename: Hasan Cem
authors.initials: HC
authors.lastname: Irkilata
authors.forename: Seref
authors.initials: S
authors.lastname: Basal
authors.forename: Ibrahim
authors.initials: I
authors.lastname: Yildirim
authors.forename: Bulent
authors.initials: B
authors.lastname: Kurt
authors.forename: Emin
authors.initials: E
authors.lastname: Aydur
authors.forename: Murat
authors.initials: M
authors.lastname: Zor
authors.forename: Serdar
authors.initials: S
authors.lastname: Goktas
mesh_terms: D000818:Animals; D004396:Coloring Agents; D005240:Feasibility Studies; D007267:Injections; D010535:Laparoscopy; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000473:pathology*; D008297:Male; D023421:Models, Animal; D010865:Pilot Projects; D012187:Retroperitoneal Space; D012394:Rosaniline Dyes; D013085:Spermatic Cord; D013552:Swine
chemical_list: D004396:Coloring Agents; D012394:Rosaniline Dyes; C008769:sulfan blue