title: Value of spontaneous hyperdensity of cerebral venous thrombosis on helical CT.
abstract: BACKGROUND
  Excluding a cerebral venous thrombosis (CVT) through imaging is a frequent request in the emergency setting. This assessment often starts by an unenhanced brain computed tomography (CT).
  
  
  OBJECTIVE
  Re-evaluate the value of spontaneous hyperdensity of CVT on helical unenhanced brain CT.
  
  
  METHODS
  Multicentric retrospective study on CVT probability based on visual assessment of spontaneous hyperdensity of cerebral venous system, performed by four blinded radiologists, individually then collectively, on a population including 14 helical unenhanced brain CTs with CVT and 102 unenhanced brain CTs without CVT (all confirmed by CT or magnetic resonance [MR] venography). Exclusion criteria: no DICOM image, symptoms >15 days, CVT indirect signs on unenhanced CT. A fifth radiologist set 768 regions of interest to measure and to compare the density within the normal venous sinuses and the CVTs.
  
  
  RESULTS
  After consensus reading, sensitivity of this sign for CVT diagnosis was 100%, specificity 95.1%, and negative predictive value (NPV) 100%, with high individual NPV (99-100%). Area under the receiver-operating characteristic curve was 0.992 after consensus (0.976-0.986 individually). The spontaneous density was significantly different (P <0.05) between normal sinuses and CVTs, with a density >70 HU reported only within the CVTs, except for the horizontal part of the superior sagittal sinus (hSSS).
  
  
  CONCLUSIONS
  The dense triangle sign on helical unenhanced brain CT has an excellent NPV to exclude a sinus thrombosis during the first 2 weeks. However, we believe that visual assessment of spontaneous hyperdensity is not sufficient for the diagnosis of CVT, with possible false-positive of the hSSS on unenhanced CT.
authors.affiliation: Department of Radiology, Teaching Military Hospital Clermont-Tonnerre, Brest, France Department of Neuroradiology, University Hospital La Cavale Blanche, Brest, France marc.garetier@wanadoo.fr.
authors.forename: Marc
authors.initials: M
authors.lastname: Garetier
authors.affiliation: Department of Radiology, Teaching Military Hospital Clermont-Tonnerre, Brest, France.
authors.forename: Jean
authors.initials: J
authors.lastname: Rousset
authors.affiliation: Department of Neuroradiology, University Hospital La Cavale Blanche, Brest, France.
authors.forename: Ernesto
authors.initials: E
authors.lastname: Pearson
authors.affiliation: Department of Neuroradiology, University Hospital La Cavale Blanche, Brest, France.
authors.forename: Valentin
authors.initials: V
authors.lastname: Tissot
authors.affiliation: Department of Neuroradiology, University Hospital La Cavale Blanche, Brest, France.
authors.forename: Jean-Christophe
authors.initials: JC
authors.lastname: Gentric
authors.affiliation: INSERM CIC 05-02, University Hospital La Cavale Blanche, Brest, France.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Nowak
authors.affiliation: Department of Neuroradiology, University Hospital Pontchaillou, Rennes, France.
authors.forename: Jean-Christophe
authors.initials: JC
authors.lastname: Ferre
authors.affiliation: Department of Neurology, University Hospital La Cavale Blanche, Brest, France.
authors.forename: Serge
authors.initials: S
authors.lastname: Timsit
authors.affiliation: Department of Neuroradiology, University Hospital La Cavale Blanche, Brest, France GETBO (Groupe d'Etude de la Thrombose de Bretagne Occidentale), Brest, France.
authors.forename: Douraied
authors.initials: D
authors.lastname: Ben Salem
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D020767:Intracranial Thrombosis / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D012372:ROC Curve; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D036542:Tomography, Spiral Computed / Q000379:methods*; D055815:Young Adult
keywords: Density; intracranial thrombosis; magnetic resonance angiography; multidetector computed tomography; sinus thrombosis; venous thrombosis