title: Sigmoid sinus diverticulum and pulsatile tinnitus: analysis of CT scans from 15 cases.
abstract: BACKGROUND
  Although the imaging features of sigmoid sinus diverticulum induced pulsatile tinnitus (PT) have been presented in some extent, detailed imaging findings still have not been systematically evaluated and precise diagnostic radiographic criteria has not been established.
  
  
  OBJECTIVE
  To examine the computed tomography (CT) characteristics of sigmoid sinus diverticulum accompanied with PT.
  
  
  METHODS
  Fifteen PT patients with sigmoid sinus diverticula proven by surgery were recruited after consenting. CT images of 15 patients were obtained and analyzed, including features of diverticula, brain venous systems, integrity of the sigmoid plate, and the degree of temporal bone pneumatization.
  
  
  RESULTS
  Sigmoid sinus diverticulum was located on the same side of PT in 15 patients. Diverticula originated at the superior curve of the sigmoid sinus in 11 patients and the descending segment of the sigmoid sinus in four patients. Sigmoid sinus diverticula focally eroded into the adjacent mastoid air cells in 12 patients and mastoid cortex in three patients. Among eight patients with unilateral dominant brain venous systems, the diverticula were seen on the dominant side in seven patients and non-dominant side in one patient. In contrast, the other seven patients showed co-dominant brain venous systems, with three presenting diverticula on the right side and four on the left. More notably, dehiscent sigmoid plate on the PT side was demonstrated in all patients. In addition, temporal bone hyper-pneumatization was found in nine patients, good and moderate pneumatization in three patients, respectively.
  
  
  CONCLUSIONS
  Dehiscent sigmoid plate and extensive temporal bone pneumatization are two important imaging characteristics of the PT induced by sigmoid sinus diverticulum.
authors.affiliation: Department of Radiology.
authors.forename: Zhaohui
authors.initials: Z
authors.lastname: Liu
authors.forename: Chengfang
authors.initials: C
authors.lastname: Chen
authors.forename: Zhenchang
authors.initials: Z
authors.lastname: Wang
authors.forename: Shusheng
authors.initials: S
authors.lastname: Gong
authors.forename: Junfang
authors.initials: J
authors.lastname: Xian
authors.forename: Yongzhe
authors.initials: Y
authors.lastname: Wang
authors.forename: Xihong
authors.initials: X
authors.lastname: Liang
authors.forename: Xiaobo
authors.initials: X
authors.lastname: Ma
authors.forename: Yi
authors.initials: Y
authors.lastname: Li
mesh_terms: D000328:Adult; D000465:Algorithms; D003287:Contrast Media; D003392:Cranial Sinuses / Q000000981:diagnostic imaging*; D004240:Diverticulum / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D007479:Iopamidol; D008297:Male; D008875:Middle Aged; D011857:Radiographic Image Interpretation, Computer-Assisted; D012189:Retrospective Studies; D014012:Tinnitus / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media; D007479:Iopamidol
keywords: Pulsatile tinnitus; computed tomography; diverticulum; sigmoid sinus; temporal bone