title: Subarachnoid hemorrhage: role of subtraction CT angiography in etiological diagnosis and pretreatment planning.
abstract: OBJECTIVE
  Subarachnoid hemorrhage (SAH) is a deleterious cerebrovascular disorder that requires prompt etiological diagnosis. We wished to evaluate the diagnostic performance of the latest generation 3D subtraction CT angiography (CTA) in etiological diagnosis and pretreatment planning of patients with suspected SAH.
  
  
  METHODS
  A total of 88 patients were included in our study and underwent both 3D subtraction CTA and digital subtraction angiography (DSA) examinations. The 3D subtraction CTA images were reviewed by two independent readers who were blinded to the results of DSA. Sensitivity, specificity, positive and negative predictive values of 3D subtraction CTA were calculated on a per-patient basis. The possibility for surgical treatment was also evaluated based on information provided by CTA alone.
  
  
  RESULTS
  According to DSA results, 72 patients were diagnosed with ruptured intracranial aneurysms, 5 patients with arteriovenous malformations, and no lesion was detected in 11 patients. Sensitivity, specificity, positive predictive value and negative predictive values of CTA for etiological evaluation of SAH were all 100%. Correct pretreatment decision was made in 67 of 70 patients based on the CTA measurements alone.
  
  
  CONCLUSIONS
  THE results of our study indicate that 3D subtraction CTA is an accurate, fast and non-invasive imaging modality that is equal to DSA in etiological evaluation and pretreatment planning of patients with suspected SAH. It may replace DSA as the first step imaging method in patients with suspected SAH, while DSA should still be reserved for case of uncertainty.
authors.affiliation: Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China - peng_xie@yahoo.com.
authors.forename: K
authors.initials: K
authors.lastname: Li
authors.forename: X
authors.initials: X
authors.lastname: Wei
authors.forename: F
authors.initials: F
authors.lastname: Lv
authors.forename: Q
authors.initials: Q
authors.lastname: Li
authors.forename: P
authors.initials: P
authors.lastname: Xie
mesh_terms: D000328:Adult; D000368:Aged; D015901:Angiography, Digital Subtraction; D002533:Cerebral Angiography / Q000379:methods*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D013345:Subarachnoid Hemorrhage / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed / Q000379:methods*; D055815:Young Adult