Carotid ultrasound criteria for detecting intracranial carotid stenosis.
OBJECTIVE
This study attempted to establish carotid ultrasound criteria for identifying stenosis of the intracranial internal carotid artery (ICA) and middle cerebral artery (MCA).


METHODS
Two hundred and fifty-five patients were enrolled. Ultrasound measurements for common carotid artery (CCA) and ICA were as follows: flow volume (FV), peak systolic velocity (PSV), end-diastolic velocity (EDV), pulsatility index (PI) and resistance index (RI). The sensitivity and specificity of the ultrasound criteria for determining intracranial ICA or MCA>or=50% stenosis were calculated.


RESULTS
The criteria identified for detecting intracranial ICA>or=50% stenosis were ICA FV<159 ml/min, ICA PSV<33 cm/s and CCA PSV<42 cm/s. When ICA PSV<33 cm/s was combined with CCA PSV<42 cm/s, sensitivity increased to 82%, with 91% specificity. The criteria identified for detecting MCA>or=50% stenosis were CCA FV<285 ml/min, ICA FV<179 ml/min, ICA PSV<33 cm/s, >35% reduction in FV in the CCA, >40% reduction in FV in ICA, and >35% reduction in PSV in ICA. When these criteria were combined, sensitivity increased to 69%, with 85% specificity.


CONCLUSIONS
This study demonstrated that ultrasound criteria are sensitive and specific for detecting intracranial ICA and MCA significant obstruction.
Lee
Jiann-Der
JD
Department of Neurology, Chang Gung Memorial Hospital, Chang Gung University, College of Medicine, Chiayi, Taiwan.
Ryu
Shan-Jin
SJ
Chang
Yeu-Jhy
YJ
Hsu
Kai-Cheng
KC
Chen
Yi-Chun
YC
Huang
Ying-Chih
YC
Lee
Meng
M
Hsiao
Ming-Chang
MC
Lee
Tsong-Hai
TH
D000792:Angiography / Q000379:methods; D001783:Blood Flow Velocity; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging*; D016893:Carotid Stenosis / Q000000981:diagnostic imaging*; D006801:Humans; D020768:Middle Cerebral Artery / Q000000981:diagnostic imaging*; D012372:ROC Curve; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D018616:Ultrasonography, Doppler, Duplex / Q000379:methods* / Q000592:standards*