title: Fracture of bony lamellae within the frontal recess after balloon catheter dilatation.
abstract: BACKGROUND
  The precise manner in which balloon catheter dilatation (BCD) alters the dimensions of the frontal recess and frontal sinus outflow tract is not well characterized. The purpose of this investigation was to determine whether BCD within the frontal recess is associated with reproducible patterns of fracture in bony lamellae, to characterize changes between pre- and postintervention measurements of the frontal sinus outflow tract, and to compare the degree of change seen with endoscopic Draf I dissection.
  
  
  METHODS
  Eight cadaver heads underwent pre- and postintervention endoscopic visualization and computed tomography (CT) of the frontal recess and frontal sinus outflow tract. Frontal recesses were assigned for either BCD or Draf I dissection. CT scans were evaluated by two reviewers (principal investigator and neuroradiologist).
  
  
  RESULTS
  Inter-rater reliability was strong for all measures (r > 0.77; p < 0.001). The sagittal and coronal dimensions of the frontal sinus outflow tract increased significantly after BCD and Draf I dissection (p < 0.028). Significantly less change was noted in average coronal dimensions of the frontal sinus outflow tract after BCD compared with Draf I dissection (0.9 +/- 0.5 mm versus 2.6 +/- 0.6 mm; p < 0.018). Mean change in the sagittal dimension was significantly less after BCD compared with Draf I dissection (1.0 +/- 0.8 mm versus 4.0 +/- 1.2 mm; p < 0.018). The anterior face of the ethmoid bulla was the most frequently fractured lamella after BCD (56%).
  
  
  CONCLUSIONS
  The sagittal and coronal dimensions of the frontal sinus outflow tract increased significantly after BCD and Draf I dissection. A significantly greater change in dimensions of the frontal sinus outflow tract is observed after Draf I dissection compared with BCD. No orbital or skull base injury was noted with either technique.
authors.affiliation: Division of Rhinology, Department of Otolaryngology-Head and Neck Surgery, Oregon Health and Science University, Portland, Oregon, USA.
authors.forename: Ayesha N
authors.initials: AN
authors.lastname: Khalid
authors.forename: Timothy L
authors.initials: TL
authors.lastname: Smith
authors.forename: James C
authors.initials: JC
authors.lastname: Anderson
authors.forename: Jess
authors.initials: J
authors.lastname: Mace
authors.forename: Nathan B
authors.initials: NB
authors.lastname: Sautter
mesh_terms: D002102:Cadaver; D002404:Catheterization / Q000009:adverse effects*; D050723:Fractures, Bone / Q000209:etiology*; D005626:Frontal Sinus / Q000000981:diagnostic imaging / Q000473:pathology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D015588:Observer Variation; D011183:Postoperative Complications; D012137:Respiratory System / Q000033:anatomy & histology; D014057:Tomography, X-Ray Computed