Sixty-four-row multisection CT angiography for detection and evaluation of ruptured intracranial aneurysms: interobserver and intertechnique reproducibility.

BACKGROUND AND PURPOSE The purpose of this work was to assess intertechnique and interobserver reproducibility of 64-row multisection CT angiography (CTA) used to detect and evaluate intracranial aneurysms. MATERIALS AND METHODS From October 2005 to November 2006, 54 consecutive patients with nontraumatic subarachnoid hemorrhage (SAH) underwent both CTA and digital substraction angiography (DSA). Four radiologists independently reviewed CT images, and 2 other radiologists reviewed DSA images. Aneurysm diameter (D), neck width (N), and the presence of a branch arising from the sac were assessed. RESULTS DSA revealed 67 aneurysms in 48 patients and no aneurysm in 6 patients. Mean sensitivity and specificity of CTA for the detection of intracranial aneurysms were, respectively, 94% and 90.2%. For aneurysms less than 3 mm, CTA had a mean sensitivity of 70.4%. Intertechnique and interobserver agreements were good for the detection of aneurysms (mean kappa = 0.673 and 0.732, respectively) and for the measurement of their necks (mean kappa = 0.753 and 0.779, respectively). Intertechnique and interobserver agreements were excellent for the measurement of aneurysm diameters (mean kappa = 0.847 and 0.876, respectively). In addition, CTA was accurate in determining the N/D ratio of aneurysms and adjacent arterial branches. However, the N/D ratio was overestimated by all of the readers at CTA. CONCLUSION Sixty-four-row multisection CTA is an imaging method with a good interobserver reproducibility and a high sensitivity and specificity for the detection and the morphologic evaluation of ruptured intracranial aneurysms. It may be used as an alternative to DSA as a first-intention imaging technique in patients with SAH.