Intracranial aneurysms: detection and characterization with MR angiography with use of an advanced postprocessing technique in a blinded-reader study

Radiology. 1997 Jun;203(3):807-14. doi: 10.1148/radiology.203.3.9169709.


Purpose: To assess magnetic resonance (MR) angiography for the detection and characterization of angiographically proved intracranial aneurysms by using an advanced method of postprocessing, in a blinded-reader study.

Materials and methods: One hundred fifty-eight vessels were examined with catheter angiography and three-dimensional time-of-flight MR angiography in 44 patients with 63 aneurysms and 15 patients with no aneurysm at catheter angiography. Postprocessing was performed off-line with an advanced multifeature-extraction, ray-tracing algorithm. MR angiograms were interpreted independently by three neuroradiologists blinded to the catheter angiographic results for presence, location, size, and morphology of the aneurysm. Proof of diagnosis was consensus reading of catheter angiograms.

Results: Mean sensitivity for detection of aneurysms was 75% (range, 70%-79%). As a screening tool (ie, detection of at least one aneurysm necessitating catheter angiography), mean sensitivity was 91% for all aneurysms and 95% for aneurysms larger than 3 mm. This method was not adequate for detection of lobulation or size of aneurysm.

Conclusion: MR angiography with an advanced method of postprocessing can result in highly sensitive, specific studies for the diagnosis of intracranial aneurysms that are of sufficient size to be considered for surgical treatment, but it is inadequate for characterization of aneurysms.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Algorithms
  • Aneurysm / diagnosis
  • Aneurysm / diagnostic imaging
  • Basilar Artery / diagnostic imaging
  • Basilar Artery / pathology
  • Carotid Artery Diseases / diagnosis
  • Carotid Artery Diseases / diagnostic imaging
  • Carotid Artery, Internal / diagnostic imaging
  • Carotid Artery, Internal / pathology
  • Catheterization
  • Cerebral Angiography
  • Humans
  • Image Enhancement / methods
  • Image Processing, Computer-Assisted* / methods
  • Intracranial Aneurysm / diagnosis*
  • Intracranial Aneurysm / diagnostic imaging
  • Magnetic Resonance Angiography*
  • Middle Aged
  • Observer Variation
  • ROC Curve
  • Sensitivity and Specificity
  • Single-Blind Method
  • Vertebral Artery / diagnostic imaging
  • Vertebral Artery / pathology