title: Temporal bone pneumatization in cystic fibrosis: a correlation with genotype?
abstract: OBJECTIVE
  Paranasal sinus pneumatization in patients with cystic fibrosis (CF) is less extensive compared to the general population and seems to be correlated to CF genotype. Interestingly, in CF patients temporal bone pneumatization (TBP) is more extensive compared to the general population, and middle ear pathology is generally uncommon in CF. It is debated whether TBP is influenced environmentally or genetically. The aim of the present study was to investigate pneumatization of the temporal bone in patients with CF and to correlate this with genotype and paranasal sinus volume.
  
  
  METHODS
  Prospective collection of data.
  
  
  METHODS
  In 104 adult CF patients, computed tomography of the temporal bone and the paranasal sinuses was performed. TBP was graded using a validated scoring system. Patients were divided into two groups, mild and severe CF, based on their mutations in the CF transmembrane conductance regulator gene.
  
  
  RESULTS
  Of the 31 patients with mild CF, 71% had extensive TBP, and of the 73 patients with severe CF, 82% had extensive pneumatization of the temporal bone. TBP did not differ significantly for CF genotype, and TBP was not correlated to paranasal sinus volume.
  
  
  CONCLUSIONS
  Whereas paranasal sinus pneumatization in CF patients seems to be related to CF genotype among other influencing factors, this study showed no correlation between TBP and CF genotype. TBP was not correlated to paranasal sinus volume. Hypothetically, in CF, pneumatization of the temporal bone is under a different influence than paranasal sinus pneumatization.
  
  
  METHODS
  4.
authors.affiliation: Departments of Pulmonology, Haga Teaching Hospital, the Hague, the Netherlands.
authors.forename: Maaike C
authors.initials: MC
authors.lastname: Berkhout
authors.forename: Cornelis J
authors.initials: CJ
authors.lastname: van Rooden
authors.forename: Ralph C
authors.initials: RC
authors.lastname: Aalbers
authors.forename: Lahssan H
authors.initials: LH
authors.lastname: el Bouazzaoui
authors.forename: Wytske J
authors.initials: WJ
authors.lastname: Fokkens
authors.forename: Evert
authors.initials: E
authors.lastname: Rijntjes
authors.forename: Harry G M
authors.initials: HG
authors.lastname: Heijerman
mesh_terms: D000328:Adult; D003550:Cystic Fibrosis / Q000000981:diagnostic imaging* / Q000235:genetics / Q000378:metabolism; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000235:genetics / Q000378:metabolism; D004247:DNA / Q000235:genetics; D004252:DNA Mutational Analysis; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D009154:Mutation; D010254:Paranasal Sinus Diseases / Q000000981:diagnostic imaging / Q000209:etiology* / Q000235:genetics; D010256:Paranasal Sinuses / Q000000981:diagnostic imaging*; D011446:Prospective Studies; D013701:Temporal Bone / Q000000981:diagnostic imaging; D014057:Tomography, X-Ray Computed
chemical_list: D019005:Cystic Fibrosis Transmembrane Conductance Regulator; D004247:DNA
keywords: Temporal bone pneumatization; cystic fibrosis; genotype; paranasal sinus volume