title: Comparison Between CTA and Digital Subtraction Angiography in the Diagnosis of Ruptured Aneurysms.
abstract: BACKGROUND
  Computerized tomography angiography (CTA) is commonly used to diagnose ruptured cerebral aneurysms with sensitivities reported as high as 97% to 100%. Studies validating CTA accuracy in the setting of subarachnoid hemorrhage (SAH) are scarce and limited by small sample sizes.
  
  
  OBJECTIVE
  To evaluate the diagnostic accuracy of CTA in detecting intracranial aneurysms in the setting of SAH.
  
  
  METHODS
  A single-center, retrospective cohort of 643 patients was reviewed. A total of 401 patients were identified whose diagnostic workup included both CTA and confirmatory digital subtraction angiography (DSA). Aneurysms missed by CTA but diagnosed by DSA were further stratified by size and location.
  
  
  RESULTS
  Three hundred and thirty aneurysms were detected by CTA while DSA detected a total of 431 aneurysms. False positive CTA results were seen for 24 aneurysms. DSA identified 125 aneurysms that were missed by CTA and 83.2% of those were <5 mm in diameter. The sensitivity of CTA was 57.6% for aneurysms smaller than 5 mm in size, and 45% for aneurysms originating from the internal carotid artery. The overall sensitivity of CTA in the setting of SAH was 70.7%.
  
  
  CONCLUSIONS
  The accuracy of CTA in the diagnosis of ruptured intracranial aneurysm may be lower than previously reported. CTA has a low sensitivity for aneurysms less than 5 mm in size, in locations adjacent to bony structures, and for those arising from small caliber parent vessels. It is our recommendation that CTA should be used with caution when used alone in the diagnosis of ruptured intracranial aneurysms.
authors.affiliation: Emory University School of Medicine, Atlanta, Georgia.
authors.forename: Lucas R
authors.initials: LR
authors.lastname: Philipp
authors.affiliation: Department of Neu-rosurgery, Emory University School of Medicine, Atlanta, Georgia.
authors.forename: D Jay
authors.initials: DJ
authors.lastname: McCracken
authors.affiliation: Emory University School of Medicine, Atlanta, Georgia.
authors.forename: Courtney E
authors.initials: CE
authors.lastname: McCracken
authors.affiliation: Emory University School of Medicine, Atlanta, Georgia.
authors.forename: Sameer H
authors.initials: SH
authors.lastname: Halani
authors.affiliation: Emory University School of Medicine, Atlanta, Georgia.
authors.forename: Brendan P
authors.initials: BP
authors.lastname: Lovasik
authors.affiliation: Emory University School of Medicine, Atlanta, Georgia.
authors.forename: Arsalaan A
authors.initials: AA
authors.lastname: Salehani
authors.affiliation: Emory University School of Medicine, Atlanta, Georgia.
authors.forename: Jason H
authors.initials: JH
authors.lastname: Boulter
authors.affiliation: Department of Neu-rosurgery, Emory University School of Medicine, Atlanta, Georgia.
authors.forename: C Michael
authors.initials: CM
authors.lastname: Cawley
authors.affiliation: Department of Neu-rosurgery, Emory University School of Medicine, Atlanta, Georgia.
authors.forename: Jonathan A
authors.initials: JA
authors.lastname: Grossberg
authors.affiliation: Department of Neu-rosurgery, Emory University School of Medicine, Atlanta, Georgia.
authors.forename: Daniel L
authors.initials: DL
authors.lastname: Barrow
authors.affiliation: Department of Neu-rosurgery, Emory University School of Medicine, Atlanta, Georgia.
authors.forename: Gustavo
authors.initials: G
authors.lastname: Pradilla
mesh_terms: D000328:Adult; D000368:Aged; D017542:Aneurysm, Ruptured / Q000000981:diagnostic imaging* / Q000601:surgery*; D015901:Angiography, Digital Subtraction / Q000379:methods / Q000592:standards*; D002533:Cerebral Angiography / Q000379:methods / Q000592:standards; D015331:Cohort Studies; D000072226:Computed Tomography Angiography / Q000379:methods / Q000592:standards*; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging* / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods
keywords: Aneurysm; Angiography; CTA; Subarachnoid hemorrhage