title: CTA in patients with acute subarachnoid haemorrhage. A comparative study with selective, digital angiography and blinded, independent review.
abstract: OBJECTIVE
  Minimal- or non-invasive methods replacing intra-arterial digital subtraction angiography (IA-DSA) would be of great importance in patients suffering from acute subarachnoid haemorrhage (SAH). The aims of this study were to compare CTA with IA-DSA in patients with acute SAH, to compare CTA interpretations with those of blinded, independent reviewers and to evaluate improvement in CTA diagnostics after 1 year of experience with CTA.
  
  
  METHODS
  During 2 years 162 patients with SAH underwent CTA as well as IA-DSA. Independent blinded review of 77 patients was performed for 1 year.
  
  
  RESULTS
  Totally 144 aneurysms were demonstrated in 119 patients at IA-DSA, while 43 patients had normal intracranial arteries. Initially 131 aneurysms were detected at CTA while 2 normal, tortuous arteries were misinterpreted as aneurysms, giving a sensitivity of 91% and a specificity of 95%. At independent blinded review the observer agreement was 87% and the kappa value 0.68.
  
  
  CONCLUSIONS
  CTA in SAH is of great value in demonstrating vascular anatomy and the exact size of an aneurysm. However, IA-DSA is still needed for diagnostic evaluation in aneurysms smaller than 5 mm in diameter, especially in those located near bony structures.
authors.affiliation: Department of Radiology, The National Hospital, University of Oslo, Norway.
authors.forename: H K
authors.initials: HK
authors.lastname: Pedersen
authors.forename: S J
authors.initials: SJ
authors.lastname: Bakke
authors.forename: J K
authors.initials: JK
authors.lastname: Hald
authors.forename: I O
authors.initials: IO
authors.lastname: Skalpe
authors.forename: I M
authors.initials: IM
authors.lastname: Anke
authors.forename: R
authors.initials: R
authors.lastname: Sagsveen
authors.forename: I A
authors.initials: IA
authors.lastname: Langmoen
authors.forename: K E
authors.initials: KE
authors.lastname: Lindegaard
authors.forename: P H
authors.initials: PH
authors.lastname: Nakstad
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D017542:Aneurysm, Ruptured / Q000150:complications / Q000000981:diagnostic imaging; D015901:Angiography, Digital Subtraction; D002533:Cerebral Angiography / Q000379:methods*; D002536:Cerebral Arteries / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000150:complications / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012422:Rupture, Spontaneous; D012680:Sensitivity and Specificity; D013345:Subarachnoid Hemorrhage / Q000000981:diagnostic imaging* / Q000209:etiology; D014057:Tomography, X-Ray Computed