The Clinical Application Value Of Transcranial Color-coded Sonography(TCCS) In Diagnosis Of The Unilateral Middle Cerebral Artery Stenosis

Objective: To assess the unilateral middle cerebral artery(MCA)stenosis and grade the stenosis by magnetic resonance angiography(MRA),and to evaluate The blood flow velocity by the Transcranial Color-codedSonography(TCCS).Methods: Patients nonconsecutive with unilateral MCA stenosis referredfor TCCS were performed MRA of the intracranial arteries between August2014 and January 2014. The degree of MCA stenosis was categorized intofour groups(normal, mild, moderate, severe) by MRA. The PSV(peaksystolic velocity), EDV(end-diastolic velocity), MFV(mean flow velocity),colored blood flow, TCCS spectrum of each MCA were recorded. ANOVAand t-testing were utilized to evaluate the difference among groups. The ROCcurve(receiver operating characteristic curve) was used to determine theoptimal velocity for different groups with the Med Calc. The consistencybetween TCCS and MRA was evaluated by Kappa value.Results: this study included 137 patients(69.3% males and 30.7%females; average age: 55.2±11.2).172(62.8%) normal, 32(11.7%) mild,26(9.5%) moderate and 44(16.1%) severe ones were determined by MRAwithin 274 MCAs. The velocity among groups was significant respectively.By TCCS, the optimal diagnostic velocity values for the normal and stenosiswere PSV=147cm/s(sensitivity=100.0%, specificity=97.6%, positivepredictive value=96.2%, negative predictive values=100.0%),EDV=71cm/s(87.2%, 99.4%, 98.9%, 92.9%), MFV=99cm/s(93.1%, 98.8%,97.9%, 96.0%); for the mild and moderate were PSV=197cm/s(88.4%, 75.0%,74.2%, 88.9%), EDV=81cm/s(88.4%, 68.7%, 69.7%, 88.0%),MFV=116cm/s(92.3%, 68.7%, 70.6%, 91.7%); for the moderate and severewere PSV=267cm/s(75.0%, 88.4%, 91.7%, 67.6%), EDV=103cm/s(90.9%,61.5%, 80.0%, 80.0%), MFV=145cm/s(95.4%, 65.3%, 82.4%, 89.5%). UsingPSV, EDV and MFV of TCCS as the diagnostic criteria respectively, theKappa value was 0.813, 0.733 and 0.786 with the MRA. In the moderate andsevere stenosis groups, the TCCS colored blood flow became slight and eveninterrupted, the spectral waveform abnormalities were common, such aspathological vortex, turbulence or unclear upper boundary and so on.Conclusion: TCCS can be used to diagnose the normal and stenosisMCA, and assess the different degrees of MCA stenosis. The results indicatedTCCS is highly consistent with MRA with PSV, EDV and MFV as thediagnostic criteria respectively. And the diagnostic accuracy of TCCS withPSV criteria was the highest. The colored blood flow and abnormal spectrummay improve the specificity of the TCCS in the diagnosis of moderate orsevere stenosis.