title: Enlarged geniculate ganglion fossa: CT sign of facial nerve canal fracture.
abstract: OBJECTIVE
  The aim of this study was to preliminarily investigate whether an enlarged geniculate ganglion fossa (GGF) on temporal bone computed tomography can diagnose GGF fracture in patients with traumatic facial paralysis by evaluating the diameter of the GGF.
  
  
  METHODS
  Thirty-six patients who underwent computed tomography before confirmation of GGF fracture on otologic surgery were recruited into a study group. Additionally, a cohort of 107 patients with no histories of head trauma, no structural abnormalities of inner ear, and no clinical symptoms of facial nerve disability who underwent computed tomography for other reasons were selected as a control group. The diameters of the GGFs of the study group were evaluated by two observers and compared retrospectively with those of the control group. Wilcoxon's test was used to compare discrepancies of both sides, and intraclass correlation coefficients were used to evaluate intraobserver and interobserver reliability.
  
  
  RESULTS
  The measurement of diameters showed good interobserver and intraobserver consistency. The discrepancy in the measurement of transdiameter between both sides of the GGF on reformatted transverse images of the study group was significantly different from that of the control group (Wilcoxon's test, P < .001). Discrepancy in the GGF on transverse images of the study group was larger than that of the control group. A significant difference existed in the discrepancy in vertical diameter between the study and control groups (Wilcoxon's test, P < .001) as well.
  
  
  CONCLUSIONS
  An enlarged GGF on temporal bone computed tomography offers an additional sign for the diagnosis of GGF fracture in patients with traumatic facial paralysis.
authors: Department of Shandong Medical Imaging Research Institute, Shandong University School of Medicine, Jinan, China.
authors: Xiaofei
authors: X
authors: Mu
authors: Yong
authors: Y
authors: Quan
authors: Jiang
authors: J
authors: Shao
authors: Jianfeng
authors: J
authors: Li
authors: Haibo
authors: H
authors: Wang
authors: Ruozhen
authors: R
authors: Gong
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D005147:Facial Bones / Q000000981:diagnostic imaging* / Q000293:injuries*; D005260:Female; D005830:Geniculate Ganglion / Q000000981:diagnostic imaging* / Q000293:injuries*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009408:Nerve Compression Syndromes / Q000000981:diagnostic imaging* / Q000209:etiology; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012887:Skull Fractures / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed / Q000379:methods*; D055815:Young Adult