KEYWORDS: Image segmentation, Arteries, Education and training, Magnetic resonance imaging, Data modeling, Independent component analysis, Simulation of CCA and DLA aggregates, 3D image processing, Scanners, Performance modeling
PurposeAtherosclerosis of the carotid artery is a major risk factor for stroke. Quantitative assessment of the carotid vessel wall can be based on cross-sections of three-dimensional (3D) black-blood magnetic resonance imaging (MRI). To increase reproducibility, a reliable automatic segmentation in these cross-sections is essential.ApproachWe propose an automatic segmentation of the carotid artery in cross-sections perpendicular to the centerline to make the segmentation invariant to the image plane orientation and allow a correct assessment of the vessel wall thickness (VWT). We trained a residual U-Net on eight sparsely sampled cross-sections per carotid artery and evaluated if the model can segment areas that are not represented in the training data. We used 218 MRI datasets of 121 subjects that show hypertension and plaque in the ICA or CCA measuring ≥1.5 mm in ultrasound.ResultsThe model achieves a high mean Dice coefficient of 0.948/0.859 for the vessel’s lumen/wall, a low mean Hausdorff distance of 0.417/0.660 mm, and a low mean average contour distance of 0.094/0.119 mm on the test set. The model reaches similar results for regions of the carotid artery that are not incorporated in the training set and on MRI of young, healthy subjects. The model also achieves a low median Hausdorff distance of 0.437/0.552 mm on the 2021 Carotid Artery Vessel Wall Segmentation Challenge test set.ConclusionsThe proposed method can reduce the effort for carotid artery vessel wall assessment. Together with human supervision, it can be used for clinical applications, as it allows a reliable measurement of the VWT for different patient demographics and MRI acquisition settings.
Atherosclerosis of the carotid artery is a major risk factor for stroke. Current studies analyze cross-sections of 3D MR black-blood images to assess the vessel wall of carotid arteries. To increase the reproducibility of quantitative biomarkers such as vessel wall thickness and radiomic features, a reliable automatic segmentation of the vessel wall in these cross-sections is essential. CNN-based segmentation is well established and has been successfully applied for 2D vessel wall and plaque segmentation. We trained a residual U-Net on sparsely sampled cross-sections that are perpendicular to the vessel’s centerline, making our method invariant to the image plane orientation. Due to the well curated training data and the usage of the vessel’s centerline as anatomical prior we are able to achieve a high mean Dice coefficient of 0.946/0.864 for the vessel’s lumen/wall and low mean average contour distance of 0.100/0.116 mm. To prove the model’s flexibility, we show that it is able to segment regions of the carotid artery that are not incorporated in the training data, achieving a similar Dice coefficient, average contour distance and Hausdorff distance. This validates the potential of the method in accurately automating carotid artery wall segmentation for any vessel cross-section. The model is also evaluated on young, healthy subjects and the 2021 Carotid Artery Vessel Wall Segmentation Challenge test set, proving its versatility.
KEYWORDS: Image segmentation, Independent component analysis, Tissues, Simulation of CCA and DLA aggregates, Arteries, Visualization, Image processing algorithms and systems, Angiography, Computed tomography, Image visualization
Measurements of the vessel lumen diameter are often used to determine the degree of atherosclerotic disease in carotid arteries. However, quantification results vary with imaging technique and acquisition settings. We aim at providing a tool that quantifies the lumen diameter on different image datasets and gives an estimate of quantification uncertainties, so that they can be taken into consideration when evaluating and comparing measurements. For the segmentation of the vessel lumen, we present an algorithm using ray-casting techniques and partial volume correction. We furthermore propose a scheme for the analysis and exploration of the lumen diameter. Finally, we present a clinically relevant application scenario, in which we explore agreement between lumen diameter estimations in corresponding computed tomography angiography, contrast-enhanced magnetic resonance angiography, time-of-flight, and subtraction images of carotid vessels with severe carotid atherosclerotic plaques.
KEYWORDS: Image segmentation, Tissues, Arteries, 3D image enhancement, Acquisition tracking and pointing, Image processing algorithms and systems, Visualization, 3D acquisition, Digital imaging
Measurements of the vessel lumen diameter are often used to determine the degree of atherosclerotic disease in carotid arteries. However, quantification results vary with imaging technique and acquisition settings. In this work, we aim at providing a tool, that quantifies the lumen diameter on different image datasets and gives an estimate of quantification uncertainties, so that they can be taken into consideration when evaluating and comparing measurements. For the segmentation of the vessel lumen we present an algorithm using ray-casting techniques and partial volume correction. We furthermore propose a scheme for analysis and exploration of the lumen diameter. Finally, we present clinically relevant application scenario, in which we explore agreement between lumen diameter estimations in corresponding CTA, CEMRA, TOF and subtraction images of carotid vessels with severe carotid atherosclerotic plaques.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.