title: Differential deposition of aerosols in the maxillary sinus of human cadavers by particle size.
abstract: BACKGROUND
  Topical delivery of nebulized antibiotics to the paranasal sinuses has been shown to improve clinical outcomes in patients with chronic sinus disease after functional endoscopic sinus surgery (FESS). The most efficient method for delivering nebulized particles to the sinuses, however, has not been established. This study investigates how the size of nebulized particles influences the efficiency of deposition in the maxillary sinus of human cadavers after FESS.
  
  
  METHODS
  Endoscopic maxillary antrostomy was performed on eight sides in four cadavers. Each cadaver's nasal vault was nebulized with technetium99m-labeled sulfur colloid particles of three size ranges. Anterior-posterior and left lateral static gamma-camera images of the head were captured with an acquisition cutoff limit of 30,000 gamma-count. Regions of interest were defined for the left and right maxillary sinus and gamma-photon counts were recorded. Analysis of variance (ANOVA) for repeated measures and paired t-test were used to determine statistical significance.
  
  
  RESULTS
  Mean diameter of particles generated was 6, 0.99, and 0.67 microm. There was a statistically significant difference in deposition between the largest particle size and the two smaller sizes, with a mean gamma-photon count of 254 for 6-microm particles versus 811 for 0.99-microm particles and 835 for 0.67-microm particles (ANOVA, p = 0.002).
  
  
  CONCLUSIONS
  Particles in the 0.67- to 0.99-microm range had improved efficiency of deposition in the maxillary sinus compared with larger particles after maxillary antrostomy. Larger particles appeared to deposit directly in the nasal vault while smaller particles were more likely to reach the maxillary sinus.
authors.affiliation: University of Minnesota, Minneapolis, Minnesota 55455, USA. hilt0054@umn.edu
authors.forename: Christopher
authors.initials: C
authors.lastname: Hilton
authors.forename: Timothy
authors.initials: T
authors.lastname: Wiedmann
authors.forename: Michele
authors.initials: M
authors.lastname: St Martin
authors.forename: Bradley
authors.initials: B
authors.lastname: Humphrey
authors.forename: Rob
authors.initials: R
authors.lastname: Schleiffarth
authors.forename: Frank
authors.initials: F
authors.lastname: Rimell
mesh_terms: D000281:Administration, Intranasal; D000336:Aerosols / Q000008:administration & dosage* / Q000493:pharmacokinetics; D002102:Cadaver; D002908:Chronic Disease; D004724:Endoscopy; D006801:Humans; D008443:Maxillary Sinus / Q000000981:diagnostic imaging / Q000378:metabolism*; D015523:Maxillary Sinusitis / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000378:metabolism; D009330:Nebulizers and Vaporizers; D013517:Otorhinolaryngologic Surgical Procedures / Q000379:methods; D011877:Radionuclide Imaging; D013667:Technetium / Q000493:pharmacokinetics*
chemical_list: D000336:Aerosols; D013667:Technetium