Neurointervention.  2016 Mar;11(1):18-23. 10.5469/neuroint.2016.11.1.18.

Arterial Wall Imaging in Symptomatic Carotid Stenosis: Delayed Enhancement on MDCT Angiography

• Ha SM
• Suh SI
• Seo WK
• Seol HY

• KMID: 2155714
• DOI: http://doi.org/10.5469/neuroint.2016.11.1.18

Abstract

OBJECTIVE
To evaluate progressive enhancement in the carotid arterial wall overlying plaque in the symptomatic side for patients with cerebrovascular symptoms until delayed phase using MDCTA.
MATERIALS AND METHODS
Twenty-one patients (all men; ages, 49-82 years; mean, 67.8 +/- 8.4 years) with recent stroke and severe extracranial carotid stenosis were retrospectively analyzed. Pre-, early- and delayed phase images of MDCTA were obtained, and Hounsfield units (HU) of carotid walls were measured. We also measured HU of the asymptomatic contralateral carotid arterial wall for comparison. Friedman's test and Wilcoxon signed-rank test were used to evaluate the differences between groups.
RESULTS
The averaged HU of the carotid wall in the symptomatic side was higher on the delayed phase (65.8 +/- 14.2 HU) compared to early arterial phase (54.2 +/- 12.6 HU). The averaged HU difference of wall enhancement between pre-contrast and delayed phase (28.0 +/- 14.8 HU) was significantly higher than the between pre-contrast and early arterial phase (16.4 +/- 12.1 HU) with P < 0.05. In analysis of the contralateral asymptomatic side, the HU difference between pre-contrast and delayed phase (15.5 +/- 12.0 HU) showed no significant higher value than between pre-contrast and early arterial phase (14.9 +/- 10.9 HU).
CONCLUSION
The pronounced enhancement of the carotid wall in the delayed phase on MDCTA was demonstrated in symptomatic patients with severe internal carotid artery stenosis. In the future, we need more comparative studies to verify this finding as one of risk stratification.

Keyword

Carotid plaque; Delayed phase; Computed tomography angiography; Stability

MeSH Terms

Angiography*
Carotid Stenosis*
Humans
Male
Retrospective Studies
Stroke

Figure

• 

  Fig. 1 A 75-year-old symptomatic male patient with acute infarctions at the left frontal and parietal lobes. MDCT axial images in the before (A), early arterial (B), and delayed (90 sec) phases (C) after administration of contrast material. The circles indicate the region of interest in the wall of the left proximal internal carotid artery (ICA). The mean HU of wall in each phase measured 58.6 HU, 73.6 HU, and 92 HU, respectively. The HU difference between the delayed (90 sec) and pre-contrast (A) phases was 33.4, while differences between early arterial (B) and pre-contrast (A) phases measured 15.

• 

  Fig. 2 A 71-year-old symptomatic male patient with acute cerebral infarction at left middle cerebral artery territory. MDCTA axial images in the before (A), early arterial (B), and delayed (90 sec) (C) phases after contrast enhancement. Compared to the asymptomatic right side (arrow), the symptomatic left carotid arterial wall overlying the plaque demonstrates more prominent and discrete enhancement in the delayed phase image (arrowheads).

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