Improvement of sensitivity and interrater reliability to detect acute stroke by dynamic perfusion computed tomography and computed tomography angiography.
OBJECTIVE
To assess the benefits of additional computed tomography perfusion (CTP) and computed tomography angiography (CTA) on the detection of early stroke, vessel occlusion, estimated infarct size, and interrater reliability.


METHODS
Sixty-seven consecutive patients underwent nonenhanced computed tomography (CT) imaging, CTA, and CTP. The final diagnosis of stroke was made from follow-up neuroimaging. A first diagnosis was made on-site by the physician on duty. Three experienced neuroradiologists blinded to follow-up findings analyzed the data set off-line, evaluated CT for signs of acute stroke, and subsequently evaluated CTP and CTA for infarction-related perfusion deficits and vessel abnormalities.


RESULTS
Computed tomography perfusion and CTA increased the time from CT start to diagnosis from 2 minutes to 10 minutes. Sensitivity to detect acute stroke increased significantly in all investigators from 0.46-0.58 to 0.79-0.90 compared with CT (<0.005). The interrater weighted kappa value increased from 0.35 to 0.64. Estimation of infarct size was not improved.


CONCLUSIONS
Computed tomography perfusion and CTA provide an effective add-on to standard CT in acute stroke imaging by significantly increasing the sensitivity and reliability of infarct detection.
Scharf
Johann
J
Department of Neuroradiology, University Hospital Mannheim, Mannheim, Germany. johann.scharf@rad.ma.uni-heidelberg.de
Brockmann
Marc A
MA
Daffertshofer
Michael
M
Diepers
Michael
M
Neumaier-Probst
Eva
E
Weiss
Christel
C
Paschke
Tilmann
T
Groden
Christoph
C
D000208:Acute Disease; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002533:Cerebral Angiography / Q000379:methods*; D002560:Cerebrovascular Circulation; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D020521:Stroke / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed / Q000379:methods*