title: The nasal septum deviation index (NSDI) based on CBCT data.
abstract: OBJECTIVE
  To assess whether three-dimensional morphometric parameters could be useful in nasal septal deviation (NSD) diagnosis and, secondarily, whether CBCT could be considered an adequate imaging technique for the proposed task.
  
  
  METHODS
  We analysed images of 46 subjects who underwent CBCT for reasons not related to this study. Two experienced operators divided all the images into healthy and NSD subjects. Subsequently, the images were segmented using ITK Snap in order to obtain the three-dimensional model of the nasal airways and compute four morphological parameters: septal deviation angle (SDA), percentage of volume difference between right and left side of the nasal airways, nasal airway total volume and a new synthetic septal deviation index (SDI). Principal component analysis (PCA) was used to unveil relationships between each variable and the global nasal airway variability.
  
  
  RESULTS
  Differences between the groups were found in SDA (p < 0.001), in volume percentage difference (p < 0.05) and in SDI (p < 0.001). PCA showed high correlation between the SDI and the first principal component (0.97, p < 0.001).
  
  
  CONCLUSIONS
  Among the analysed parameters, SDI seemed to be the most suitable for the quantitative assessment of NSD, and CBCT allowed accurate assessment of airway morphology.
authors.affiliation: 1 Functional Anatomy Research Center (FARC), Laboratorio di Anatomia Funzionale, dell'Apparato Stomatognatico, Dipartimento di Scienze Biomediche per la Salute, Facoltà di Medicina e Chirurgia, Università degli Studi di Milano, Milano, Italy.
authors.forename: Marina
authors.initials: M
authors.lastname: Codari
authors.affiliation: 1 Functional Anatomy Research Center (FARC), Laboratorio di Anatomia Funzionale, dell'Apparato Stomatognatico, Dipartimento di Scienze Biomediche per la Salute, Facoltà di Medicina e Chirurgia, Università degli Studi di Milano, Milano, Italy.
authors.forename: Matteo
authors.initials: M
authors.lastname: Zago
authors.affiliation: 1 Functional Anatomy Research Center (FARC), Laboratorio di Anatomia Funzionale, dell'Apparato Stomatognatico, Dipartimento di Scienze Biomediche per la Salute, Facoltà di Medicina e Chirurgia, Università degli Studi di Milano, Milano, Italy.|2 Dipartimento di Scienze Cliniche e di Comunità, Facoltà di Medicina e Chirurgia, Università degli Studi di Milano, Milano, Italy.
authors.forename: Giulia A
authors.initials: GA
authors.lastname: Guidugli
authors.affiliation: 1 Functional Anatomy Research Center (FARC), Laboratorio di Anatomia Funzionale, dell'Apparato Stomatognatico, Dipartimento di Scienze Biomediche per la Salute, Facoltà di Medicina e Chirurgia, Università degli Studi di Milano, Milano, Italy.
authors.forename: Valentina
authors.initials: V
authors.lastname: Pucciarelli
authors.affiliation: 1 Functional Anatomy Research Center (FARC), Laboratorio di Anatomia Funzionale, dell'Apparato Stomatognatico, Dipartimento di Scienze Biomediche per la Salute, Facoltà di Medicina e Chirurgia, Università degli Studi di Milano, Milano, Italy.
authors.forename: Gianluca M
authors.initials: GM
authors.lastname: Tartaglia
authors.affiliation: 2 Dipartimento di Scienze Cliniche e di Comunità, Facoltà di Medicina e Chirurgia, Università degli Studi di Milano, Milano, Italy.|3 Ospedale San Giuseppe, Milano, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Ottaviani
authors.affiliation: 3 Ospedale San Giuseppe, Milano, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Righini
authors.affiliation: 1 Functional Anatomy Research Center (FARC), Laboratorio di Anatomia Funzionale, dell'Apparato Stomatognatico, Dipartimento di Scienze Biomediche per la Salute, Facoltà di Medicina e Chirurgia, Università degli Studi di Milano, Milano, Italy.
authors.forename: Chiarella
authors.identifier: http://orcid.org/0000-0001-6532-6464
authors.initials: C
authors.lastname: Sforza
mesh_terms: D000328:Adult; D054893:Cone-Beam Computed Tomography / Q000379:methods*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D008297:Male; D008875:Middle Aged; D009296:Nasal Cavity / Q000000981:diagnostic imaging; D009300:Nasal Septum / Q000002:abnormalities* / Q000000981:diagnostic imaging; D009929:Organ Size; D025341:Principal Component Analysis; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods
keywords: CBCT; Computer-assisted; image interpretation; nasal septum