RT Journal Article
SR Electronic
T1 Timing-Invariant CT Angiography Derived from CT Perfusion Imaging in Acute Stroke: A Diagnostic Performance Study
JF American Journal of Neuroradiology
JO Am. J. Neuroradiol.
FD American Society of Neuroradiology
SP 1834
OP 1838
DO 10.3174/ajnr.A4376
VO 36
IS 10
A1 E.J. Smit
A1 E.-j. Vonken
A1 F.J.A. Meijer
A1 J.W. Dankbaar
A1 A.D. Horsch
A1 B. van Ginneken
A1 B. Velthuis
A1 I. van der Schaaf
A1 M. Prokop
YR 2015
UL http://www.ajnr.org/content/36/10/1834.abstract
AB BACKGROUND AND PURPOSE: Timing-invariant (or delay-insensitive) CT angiography derived from CT perfusion data may obviate a separate cranial CTA in acute stroke, thus enhancing patient safety by reducing total examination time, radiation dose, and volume of contrast material. We assessed the diagnostic accuracy of timing-invariant CTA for detecting intracranial artery occlusion in acute ischemic stroke, to examine whether standard CTA can be omitted.MATERIALS AND METHODS: Patients with suspected ischemic stroke were prospectively enrolled and underwent CTA and CTP imaging at admission. Timing-invariant CTA was derived from the CTP data. Five neuroradiologic observers assessed all images for the presence and location of intracranial artery occlusion in a blinded and randomized manner. Sensitivity and specificity of timing-invariant CTA and standard CTA were calculated by using an independent expert panel as the reference standard. Interrater agreement was determined by using κ statistics.RESULTS: We included 108 patients with 47 vessel occlusions. Overall, standard CTA and timing-invariant CTA provided similar high diagnostic accuracy for occlusion detection with a sensitivity of 96% (95% CI, 90%–100%) and a specificity of 100% (99%–100%) for standard CTA and a sensitivity of 98% (95% CI, 94%–100%) and a specificity of 100% (95% CI, 100%–100%) for timing-invariant CTA. For proximal large-vessel occlusions, defined as occlusions of the ICA, basilar artery, and M1, the sensitivity and specificity were 100% (95% CI, 100%–100%) for both techniques. Interrater agreement was good for both techniques (mean κ value, 0.75 and 0.76).CONCLUSIONS: Timing-invariant CTA derived from CTP data provides diagnostic accuracy similar to that of standard CTA for the detection of artery occlusions in acute stroke.