Discrimination of plaque from sluggish-flow-related hyperintense artifact on high-resolution magnetic resonance
Feng Ouyang1, Qin Wu1, Jie Liu1
1Department of Radiology, The First Affiliated Hospital, Jiangxi Medical College, Nanchang University, China; Clinical Research Center for Medical Imaging in Jiangxi Province, Nanchang, China.
Objective:
The degree of plaque enhancement is critical for estimating the risk of incident and recurrent ischemic events in intracranial atherosclerotic stenosis. Hyperintensity caused by regional slow flow may confound plaque assessment. This study aimed to investigate methods for differentiating plaque from sluggish-flow-related hyperintense artifacts on high-resolution magnetic resonance vessel wall imaging (HR-VWI).
Methods:
Imaging data from January 2020 to June 2025 were retrospectively reviewed for patients with intracranial atherosclerotic stenosis who underwent both HR-VWI and computed tomography angiography (CTA). By comparison with CTA, features of plaque and adjacent sluggish-flow-related hyperintense artifacts on HR-VWI were analyzed.
Results:
Fifty-five patients (mean age 54.9 ± 9.35 years; 37 male and 18 female) with severe atherosclerotic stenosis or occlusion of the middle cerebral artery (MCA) were evaluated. Compared with plaque, slow-flow-related hyperintensity involved longer segments, showed a higher enhancement ratio, a lower standard deviation of signal intensity (SI) on pre-contrast images, and a higher mean post-contrast SI (all P < 0.05). All sluggish-flow-related hyperintensities exhibited central enhancement. The central enhancement pattern achieved an accuracy of 0.84, a sensitivity of 100%, and a specificity of 69% for discriminating plaque from sluggish-flow-related hyperintensities. Multivariable conditional logistic regression identified posterior enhancement location (OR, 16.62; 95% CI, 3.40-81.17; P < 0.001), post-contrast mean SI (odds ratio [OR], 1.33; 95% CI, 1.05-1.67; P = 0.016), and post-contrast SI standard deviation (OR, 0.05; 95% CI, 0.004-0.68; P = 0.024) as independent discriminators.
Conclusion:
Enhancement pattern, distribution location, and quantitative signal intensity parameters are useful clues for identifying sluggish-flow-related artifacts in patients with severe MCA stenosis or occlusion. Accurate interpretation still hinges on a standardized evaluation of the lumen.
