title: Diagnosing intracranial aneurysms with MR angiography: systematic review and meta-analysis.
abstract: OBJECTIVE
  The aim of this study was to evaluate the sensitivity and specificity of MR angiography (MRA) in the diagnosis of ruptured and unruptured intracranial aneurysms.
  
  
  METHODS
  A systematic search was performed on 4 electronic databases on relevant articles that were published from January 1998 to October 2013. Inclusion criteria were met by 12 studies that compared MRA with digital subtraction angiography as reference standard. Two independent reviewers evaluated the methodological quality of the studies. Data from eligible studies were extracted and used to construct 2×2 contingency tables on a per-aneurysm level. Pooled estimates of sensitivity and specificity were calculated for all studies and subgroups of studies. Heterogeneity was tested, and risk for publication bias was assessed.
  
  
  RESULTS
  Included studies were of high methodological quality. Studies with larger sample size tended to have higher diagnostic performance. Most studies used time-of-flight MRA technique. Among the 960 patients assessed, 772 aneurysms were present. Heterogeneity with reference to sensitivity and specificity was moderate to high. Pooled sensitivity of MRA was 95% (95% confidence interval, 89%-98%), and pooled specificity was 89% (95% confidence interval, 80%-95%). False-negative and false-positive aneurysms detected on MRA were mainly located at the skull base and middle cerebral artery. Freehand 3-dimensional reconstructions performed by the radiologist significantly increased diagnostic performance. Studies performed on 3 Tesla showed a trend toward higher performance (P=0.054).
  
  
  CONCLUSIONS
  Studies on diagnostic performance of MRA show high sensitivity with large variation in specificity in the detection of intracranial aneurysms.
authors: From the Department of Radiology (A.M.H.S., B.A.J.M.W., R.d.G., W.H.v.Z.), and Department of Epidemiology (P.J.N.), Maastricht University Medical Centre, Maastricht, The Netherlands.
authors: Anna M H
authors: AM
authors: Sailer
authors: Bart A J M
authors: BA
authors: Wagemans
authors: Patricia J
authors: PJ
authors: Nelemans
authors: Rick
authors: R
authors: de Graaf
authors: Willem H
authors: WH
authors: van Zwam
mesh_terms: D017542:Aneurysm, Ruptured / Q000175:diagnosis; D002533:Cerebral Angiography / Q000379:methods*; D003627:Data Interpretation, Statistical; D005188:False Negative Reactions; D005189:False Positive Reactions; D006801:Humans; D002532:Intracranial Aneurysm / Q000175:diagnosis*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D012372:ROC Curve; D018401:Sample Size; D014057:Tomography, X-Ray Computed
keywords: intracranial aneurysm; magnetic resonance angiography; meta-analysis