title: Renal tumor models: evaluation of ease of implementation, quality of composition, and imaging characteristics.
abstract: OBJECTIVE
  With the rise in detection of small renal masses that are amenable to nephron-sparing surgical approaches, there has been an increasing need for renal tumor models that create discrete lesions suitable for training exercises. We aim to investigate a handful of commonly used compounds, subjectively evaluating their ease of implementation and imaging characteristics.
  
  
  METHODS
  After an initial ex vivo study, we selected five compounds for an in vivo porcine investigation. These compounds included metagel with barium, Smooth-Cast 320, Silfome with and without barium, and Kromopan. The compounds were injected under laparoscopic guidance with the aim of creating discrete renal tumors. The kidneys were then imaged under ultrasonography and CT. The animals were euthanized, and nephrectomy was performed. Handling characteristics were noted.
  
  
  RESULTS
  All compounds were relatively easy to inject. Most of the compounds were susceptible to some degree of subcapsular spread. Kromopan had a high propensity for infiltration of the collecting system. On imaging, metagel was clearly distinguishable from normal renal parenchyma on both CT and ultrasonography. Silfome and Smooth-Cast were difficult to resolve on ultrasonography. Metagel was prone to rupture during surgical manipulation.
  
  
  CONCLUSIONS
  No single compound provided the ideal combination of ease of implementation, resistance to extravasation, ease of resolution on imaging, and resistance to rupture. Therefore, compound selection should be dictated by the particular aims of a training simulation.
authors.affiliation: Washington University School of Medicine, Department of Surgery, Division of Urologic Surgery, Saint Louis, Missouri 63110, USA. benwayb@wustl.edu
authors.forename: Brian M
authors.initials: BM
authors.lastname: Benway
authors.forename: Jose M
authors.initials: JM
authors.lastname: Cabello
authors.forename: Alana C
authors.initials: AC
authors.lastname: Desai
authors.forename: Robert S
authors.initials: RS
authors.lastname: Figenshau
authors.forename: Sam B
authors.initials: SB
authors.lastname: Bhayani
mesh_terms: D000818:Animals; D007267:Injections; D007680:Kidney Neoplasms / Q000000981:diagnostic imaging*; D008954:Models, Biological; D034421:Sus scrofa; D014057:Tomography, X-Ray Computed