Optimal flow velocity of transcranial doppler in diagnosing and grading middle cerebral artery stenosis in comparison with magnetic resonance angiography
- VernacularTitle:经颅多普勒超声评估大脑中动脉狭窄程度的最佳速度值
- Author:
Junyan LIU
;
Shan GAO
;
Kasing WONG
- Publication Type:Journal Article
- Keywords:
Ultrasonography, doppler, transcranial;
Middle cerebral artery;
Cerebrovascular disorders;
Diagnosis;
Reference standards
- From:
Chinese Journal of Neurology
1999;0(06):-
- CountryChina
- Language:Chinese
-
Abstract:
Objective To evaluate the best cutoff points of flow velocity for diagnosing and grading middle cerebral artery (MCA) stenosis as compared with magnetic resonance angiography (MRA) in a large group of asymptomatic patients. Methods We diagnosed 148 MCA stenostic patients with conventional method using EME-TC2000 transcranial Doppler (TCD) by a single reseach technician. All patients were given a MRA within 1 week after TCD examination. The severity of MCA stenosis was categorized as normal-mild (75% and void of flow signal) on the basis of the amount of signal loss and the lumen reduction of MCA in MRA . According to the different systolic velocities as following ≥130 cm/s, ≥140 cm/s , ≥150 cm/s, ≥160 cm/s, ≥ 170 cm/s, we drown different ROC(receiver operator characteristic) curves and determined which cutoff point was the best for diagnosing and grading the MCA stenosis.Results The numbers of vessel with normal, moderate and severe stenosis were 75, 112,109 respectively in MRA, their mean MCA velocities are (121?22) cm/s, (155?21) cm/s, (199?43) cm/s respectively in TCD, there was a obvious difference of systolic velocity among these three groups. Through calculating the bigest areas under ROC, we concluded that the optimal cutoff points for diagnosing MCA stenosis was 140 cm/s (areas under ROC was 0.87, P
