title: Rethinking nasal tip support: a finite element analysis.
abstract: OBJECTIVE
  We employ a nasal tip finite element model (FEM) to evaluate contributions of two of the three major tip support mechanisms: attachments between the upper and lower lateral cartilages and attachment of the medial crura to the caudal septum.
  
  
  METHODS
  The nasal tip FEM computed stress distribution and strain energy density (SED) during nasal tip compression. We examined the impact of attachments between the upper and lower lateral cartilages and the attachment of the medial crura to the caudal septum on nasal tip support.
  
  
  METHODS
  The FEM consisted of three tissue components: bone, cartilage, and skin. Four models were created: A) control model with attachments present at the scroll and caudal septum; B) simulated disruption of scroll; C) simulated disruption of medial crura attachments to caudal septum; and D) simulated disruption of scroll and medial crura attachments to caudal septum. Spatial distribution of stress and SED were calculated.
  
  
  RESULTS
  The keystone, intermediate crura, caudal septum, and nasal spine demonstrated high concentration of stress distribution. Across all models, there was no difference in stress distribution. Disruption of the scroll resulted in 1% decrease in SED. Disruption of the medial crura attachments to the caudal septum resulted in 4.2% reduction in SED. Disruption of both scroll and medial crural attachments resulted in 9.1% reduction in SED.
  
  
  CONCLUSIONS
  The nasal tip FEM is an evolving tool to study structural nasal tip dynamics and demonstrates the loss of nasal tip support with disruption of attachments at the scroll and nasal base.
  
  
  METHODS
  N/A.
authors.affiliation: Department of Otolaryngology, University of California at Irvine, Irvine, California.
authors.forename: David
authors.initials: D
authors.lastname: Shamouelian
authors.forename: Ryan P
authors.initials: RP
authors.lastname: Leary
authors.forename: Cyrus T
authors.initials: CT
authors.lastname: Manuel
authors.forename: Rani
authors.initials: R
authors.lastname: Harb
authors.forename: Dmitriy E
authors.initials: DE
authors.lastname: Protsenko
authors.forename: Brian J F
authors.initials: BJ
authors.lastname: Wong
mesh_terms: D003198:Computer Simulation; D017076:Computer-Aided Design; D020342:Finite Element Analysis; D006801:Humans; D055171:Nasal Cartilages / Q000601:surgery; D009300:Nasal Septum / Q000601:surgery; D012225:Rhinoplasty / Q000379:methods*
keywords: Nasal tip support; finite element method; rhinoplasty