title: Sanna Classification and Prognosis of Cholesteatoma of the Petrous Part of the Temporal Bone: A Retrospective Series of 81 Patients.
abstract: To determine how classification of petrous bone cholesteatomas (PBCs) using the 5-point Sanna classification can predict major structural involvement, facial nerve outcomes, hearing outcomes, postoperative complications, and disease recurrence.
  
  
  
  Retrospective case series.
  
  
  
  Tertiary referral center in Bergamo, Italy.
  
  
  
  Eighty-one sequential patients with radiologic and surgically confirmed diagnoses of PBC treated at a single tertiary referral center during a 20-year period.
  
  
  
  Major structural involvement, facial nerve outcomes, hearing outcomes, postoperative cerebrospinal fluid leak, and disease recurrence were evaluated on the basis of Sanna classification.
  
  
  
  Using the Sanna classification, 70% (57) were supralabyrinthine, 12% (10) infralabyrinthine, 7% (6) infralabyrinthine-apical, 5% (4) apical, and 5% (4) massive. Massive classification was statistically significantly associated with cochlear involvement (p = 0.009) and internal auditory canal involvement (p = 0.02). The infralabyrinthine-apical class was associated with carotid canal involvement (p = 0.03). Facial nerve interruption was observed in 35% of patients and most frequently in the apical group (75%). Neither hearing nor facial nerve outcomes were associated with Sanna classification. House-Brackmann score improved or was maintained postoperatively in 89% of patients.
  
  
  
  The Sanna classification provides anatomic detail on location of PBCs and is predictive of IAC, cochlear, and carotid artery involvement. However, classification systems for this rare condition continue to pose a challenge in being able to accurately predict facial nerve and hearing outcomes in surgical obliteration of PBC.
authors.affiliation: *Ospedali Riuniti, Bergamo, Italy†Division of Otolaryngology-Head and Neck Surgery, University of Alberta, Edmonton, Alberta, Canada‡Azienda Ospedaliera Bolognini, Seriate, Italy.
authors.forename: Giovani
authors.initials: G
authors.lastname: Danesi
authors.forename: Timothy
authors.initials: T
authors.lastname: Cooper
authors.forename: Davide Thomas
authors.initials: DT
authors.lastname: Panciera
authors.forename: Vito
authors.initials: V
authors.lastname: Manni
authors.forename: David W J
authors.initials: DW
authors.lastname: Côté
mesh_terms: D002781:Cholesteatoma / Q000145:classification* / Q000150:complications / Q000473:pathology*; D005260:Female; D006801:Humans; D007558:Italy; D008297:Male; D010579:Petrous Bone / Q000473:pathology*; D011379:Prognosis; D012008:Recurrence; D012189:Retrospective Studies; D062606:Tertiary Care Centers