title: Microdebriders used in functional endoscopic sinus surgery: secondary analysis and validation of a new tissue model.
abstract: OBJECTIVE
  To validate a previously reported in vitro tissue model for microdebrider comparison and determine which microdebrider, tissue type, blade type, and suction strength is most efficient. Specifically, the goal of the secondary analysis is to expand on the results of the preliminary analysis by increasing the sample size, and introduce an aspiration efficiency score (AES) to facilitate microdebrider comparison.
  
  
  METHODS
  Prospective randomized comparison.
  
  
  METHODS
  A prospective randomized comparison of the Diego Powered Dissector and XPS 3000 Powered ENT System was conducted using a soft tissue and a firm tissue model. In addition to evaluating tissue aspiration with straight and angled blades, clogging rates and clearance times were measured. Both standard wall suction and liposuction were used. Basic statistical analysis, a one-way analysis of variance, and a post hoc Student's t test were performed to compare outcomes.
  
  
  RESULTS
  With standard wall suction, the microdebriders were equivalent for the overall microdebrider comparison. For the ''head to head'' comparison with standard wall suction, the devices were also equivalent when using the straight blades, but the XPS 3000 aspirated more tissue when using the angled blades. With liposuction, the XPS 3000 and liposuction independently aspirated more tissue but clogged more often compared with the Diego PD and regular suction. The aspiration efficiency of soft tissue (oysters) and straight blades was superior compared with firm tissue (scallops) and angled blades. For the ''head to head'' comparison with liposuction, the XPS 3000 aspirated more tissue regardless of tissue type, but the Diego PD clogged less with firm tissue (scallops). Overall, the AES favored the XPS 3000, soft tissue (oysters), straight blades, and liposuction.
  
  
  CONCLUSIONS
  Our tissue model represents a reliable and reproducible means of microdebrider comparison. Statistically significant differences between the Diego PD and XPS 3000, as well as between tissue types, blade types, and suction strengths, are reported. Using these results, microdebrider manufacturers can adopt similar tissue models, expand on the current AES, and include other commercially available microdebrider devices to test and report product performance to the consumer. Perhaps an optimal open to closed ratio or liposuction pressure can be determined that yields the greatest tissue aspiration with the fewest number of clogs.
authors.affiliation: Department of Otolaryngology Head and Neck Surgery, University of Miami School of Medicine/Jackson Memorial Medical Center, Miami, FL 33136, USA.
authors.forename: Sandeep P
authors.initials: SP
authors.lastname: Dave
authors.forename: Marek
authors.initials: M
authors.lastname: Polak
authors.forename: Roy R
authors.initials: RR
authors.lastname: Casiano
mesh_terms: D000818:Animals; D003646:Debridement / Q000295:instrumentation* / Q000379:methods; D004724:Endoscopy; D004867:Equipment Design; D008954:Models, Biological; D008974:Mollusca; D009298:Nasal Polyps / Q000601:surgery*; D010125:Ostreidae; D010256:Paranasal Sinuses / Q000601:surgery*; D011446:Prospective Studies; D011897:Random Allocation; D013396:Suction