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Updated: Aug 16, 2026
Point of Care Transcranial Color-Coded Duplex Ultrasound of the Middle Cerebral Artery
Published on: August 9, 2024
Absent middle cerebral artery signal in transcranial color-coded sonography: a reliable indicator of occlusion?
Yi-Chun Chen1, Sien-Tsong Chen, Chi-Jen Chen
1Department of Neurology, Chang Gung Memorial Hospital, Lin-kou Medical Center, Kueishan, Taoyuan, Taiwan, ROC.
Insights
Transcranial color-coded sonography (TCCS) has limited accuracy for detecting middle cerebral artery (MCA) stem occlusion. Cerebral angiography is essential for confirming MCA stem occlusion, though TCCS can identify non-occluded MCA stems.
Area of Science:
- Neurology
- Vascular Neurology
- Neuroimaging
Background:
- Assessing the diagnostic accuracy of transcranial color-coded sonography (TCCS).
- Evaluating TCCS for detecting middle cerebral artery (MCA) stem occlusion.
- Comparing TCCS findings with cerebral angiography results.
Purpose of the Study:
- To determine the accuracy of TCCS in identifying MCA stem occlusion.
- To compare TCCS performance against cerebral angiography.
- To investigate factors influencing MCA stem insonation via TCCS.
Main Methods:
- Retrospective analysis of 419 patients undergoing TCCS and cerebral angiography.
- Diagnosis of MCA stem occlusion using digital subtraction angiography and/or CT angiography.
- Defined sonographic criteria for MCA stem occlusion based on signal presence/absence in MCA stem and reference arteries.
Main Results:
- Factors like carotid artery stenosis, MCA stem stenosis, female gender, and age influenced MCA stem insonation.
- Reduced MCA stem insonation rates were observed with increasing carotid stenosis (69.1% vs. 45.6%).
- In patients with <50% carotid stenosis, TCCS showed high specificity (89.6%) but low sensitivity (54.5%) for MCA stem occlusion, with an overall accuracy of 88.9%.
Conclusions:
- Absent MCA stem signal on TCCS can be due to occlusion/stenosis or ipsilateral carotid artery stenosis.
- TCCS has limited value in definitively diagnosing MCA stem occlusion.
- Cerebral angiography remains necessary for confirming MCA stem occlusion; TCCS is useful for identifying non-occluded MCA stems.
Background:
Assess the accuracy of transcranial color-coded sonography (TCCS) for detecting middle cerebral artery (MCA) stem occlusion and compare it with cerebral angiography.
Methods:
This study enrolled a series of patients who received TCCS and cerebral angiography at the Department of Neurology in Chang Gung Memorial Hospital, Linkou Medical Center, Taoyuan, Taiwan, between January 1997 and July 2003. MCA stem occlusion was diagnosed based on digital subtraction angiography and/or computed tomographic angiography. The effect of the supplying artery on the insonation of MCA stem was considered. The sonographic criteria for MCA stem occlusion were defined as absent MCA stem signal + visible signal on the reference arteries, including ipsilateral posterior cerebral artery, ipsilateral anterior cerebral artery or contralateral MCA stem.
Results:
A total of 419 consecutive patients were enrolled. Factors that significantly influenced MCA stem insonation included > or =50% ipsilateral carotid artery stenosis, > or =50% MCA stem stenosis, female gender, and age > or =60 years. Comparing patients with <50% and those with > or =50% carotid stenosis, the MCA stem insonation rate was significantly reduced from 69.1% to 45.6% (p < 0.001). In patients with <50% ipsilateral carotid artery stenosis, the sonographic criteria had a positive predictive value of 10.5% and a negative predictive value of 98.9%, and could predict MCA stem occlusion with high specificity but low sensitivity (specificity = 89.6, sensitivity = 54.5, overall accuracy = 88.9, p < 0.001).
Conclusion:
Absent MCA stem signal may result from MCA stem occlusion/tight stenosis and tight stenosis of ipsilateral carotid arteries, and has a limited value in detecting MCA stem occlusion. TCCS can be useful in identifying nonoccluded MCA stem, and cerebral angiography is necessary to confirm MCA stem occlusion.
