Hyperdense middle cerebral artery sign on CT: efficacy in detecting middle cerebral artery thrombosis.
The hyperdense middle cerebral artery sign is a CT predictor of the development of a large cerebral infarct. The limits of detectability were tested in a blinded, then unblinded analysis of CT scans from 25 acute stroke patients. In the initial blinded analysis, sign detection exhibited the following mean values: sensitivity, 78.5%; specificity, 93.4%; positive predictive value, 66%; negative predictive value, 96.4%; accuracy, 91.3%. Kappa statistics analysis indicated poor interobserver agreement (k = .38). Results of unblinded analysis were as follows: sensitivity, 69%; specificity, 94.4%; positive predictive value, 82.8%; negative predictive value, 88.7%; accuracy, 87.3%. There was fair unblinded interobserver agreement (k = .53). Unblinded analysis had a lower false-positive frequency and did not increase the number of true-positive determinations. We conclude that detection of the hyperdense middle cerebral artery sign on CT scans by multiple observers is a sensitive, accurate, and predictive indicator of middle cerebral artery thromboembolism.
Tomsick
T A
TA
Department of Radiology, University of Cincinnati Medical Center, OH 45267-0742.
Brott
T G
TG
Chambers
A A
AA
Fox
A J
AJ
Gaskill
M F
MF
Lukin
R R
RR
Pleatman
C W
CW
Wiot
J G
JG
Bourekas
E
E
D000208:Acute Disease; D002539:Cerebral Arterial Diseases / Q000000981:diagnostic imaging*; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D002542:Intracranial Embolism and Thrombosis / Q000000981:diagnostic imaging*; D008297:Male; D015588:Observer Variation; D011237:Predictive Value of Tests; D012107:Research Design; D014057:Tomography, X-Ray Computed