Serial measurements of coronary plaque volume have been used to evaluate drug efficacy in atherosclerotic progression. However, the usefulness of computed tomography for this purpose is unknown. We... Show moreSerial measurements of coronary plaque volume have been used to evaluate drug efficacy in atherosclerotic progression. However, the usefulness of computed tomography for this purpose is unknown. We investigated whether the change in total plaque volume on coronary computed tomographic angiography is associated with the change in segment plaque volume on intravascular ultrasound.We prospectively enrolled 11 consecutive patients (mean age, 56.3 +/- 5 yr; 6 men) who were to undergo serial invasive coronary angiographic examinations with use of grayscale intravascular ultrasound and coronary computed tomography, performed <180 days apart at baseline and from 1 to 2 years later. Subjects underwent 186 serial measurements of total plaque volume on coronary computed tomography and 22 of segmental plaque volume on intravascular ultrasound. We used semiautomated software to examine percentage relationships and changes between total plaque and segmental plaque volumes.No significant correlations were found between percentages of total coronary and segment coronary plaque volume, nor between normalized coronary plaque volume. However, in the per-patient analysis, there were strong correlations between the imaging methods for changes in total coronary and segment coronary plaque volume (r=0.62; P=0.04), as well as normalized plaque volume (r=0.82; P=0.002).Per-patient change in plaque volume on coronary computed tomography is significantly associated with that on intravascular ultrasound. Computed tomographic angiography may be safer and more widely available than intravascular ultrasound for evaluating atherosclerotic progression in coronary arteries. Larger studies are warranted. Show less
Deseive, S.; Straub, R.; Kupke, M.; Broersen, A.; Kitslaar, P.H.; Massberg, S.; ... ; Hausleiter, J. 2018
Background: To investigate the incremental prognostic value of low-attenuation plaque volume (LAPV) from coronary CT angiography datasets.Methods: Quantification of LAPV was performed using... Show moreBackground: To investigate the incremental prognostic value of low-attenuation plaque volume (LAPV) from coronary CT angiography datasets.Methods: Quantification of LAPV was performed using dedicated software equipped with an adaptive plaque tissue algorithm in 1577 patients with suspected CAD. A combination of death and acute coronary syndrome was defined as primary endpoint. To assess the incremental prognostic value of LAPV, parameters were added to a baseline model including clinical risk and obstructive coronary artery disease (CAD), a baseline model including clinical risk and calcium scoring (CACS) and a baseline model including clinical risk and segment involvement score (SIS).Results: Patients were followed for 5.5 years either by telephone contact, mail or clinical visits. The primary endpoint occurred in 30 patients. Quantified LAPV provided incremental prognostic information beyond clinical risk and obstructive CAD (c-index 0.701 vs. 0.767, p<.001), clinical risk and CACS (c-index 0.722 vs. 0.771, p<.01) and clinical risk and SIS (c-index 0.735 vs. 0.771, p<.01. A combined approach using quantified LAPV and clinical risk significantly improved the stratification of patients into different risk categories compared to clinical risk alone (categorical net reclassification index 0.69 with 95% CI 0.27 and 0.96, p<.001). The combined approach classified 846 (53.6%) patients as low risk (annual event rate 0.04%), 439 (27.8%) patients as intermediate risk (annual event rate 0.5%) and 292 (18.5%) patients as high risk (annual event rate 0.99%).Conclusion: Quantification of LAPV provides incremental prognostic information beyond established CT risk patterns and permits improved stratification of patients into different risk categories. Show less
Semi-automated software can provide quantitative assessment of atherosclerotic plaques on coronary CT angiography (CTA). The relationship between established qualitative high-risk plaque features... Show moreSemi-automated software can provide quantitative assessment of atherosclerotic plaques on coronary CT angiography (CTA). The relationship between established qualitative high-risk plaque features and quantitative plaque measurements has not been studied. We analyzed the association between quantitative plaque measurements and qualitative high-risk plaque features on coronary CTA. We included 260 patients with plaque who underwent coronary CTA in the Rule Out Myocardial Infarction/Ischemia Using Computer Assisted Tomography (ROMICAT) II trial. Quantitative plaque assessment and qualitative plaque characterization were performed on a per coronary segment basis. Quantitative coronary plaque measurements included plaque volume, plaque burden, remodeling index, and diameter stenosis. In qualitative analysis, high-risk plaque was present if positive remodeling, low CT attenuation plaque, napkin-ring sign or spotty calcium were detected. Univariable and multivariable logistic regression analyses were performed to assess the association between quantitative and qualitative high-risk plaque assessment. Among 888 segments with coronary plaque, high-risk plaque was present in 391 (44.0%) segments by qualitative analysis. In quantitative analysis, segments with high-risk plaque had higher total plaque volume, low CT attenuation plaque volume, plaque burden and remodeling index. Quantitatively assessed low CT attenuation plaque volume (odds ratio 1.12 per 1 mm(3), 95% CI 1.04-1.21), positive remodeling (odds ratio 1.25 per 0.1, 95% CI 1.10-1.41) and plaque burden (odds ratio 1.53 per 0.1, 95% CI 1.08-2.16) were associated with high-risk plaque. Quantitative coronary plaque characteristics (low CT attenuation plaque volume, positive remodeling and plaque burden) measured by semi-automated software correlated with qualitative assessment of high-risk plaque features. Show less
PurposeAutomatically extracted coronary artery trees (CATs) from coronary computed tomography angiography imagescould contain incorrect extractions which require manual corrections before they can... Show morePurposeAutomatically extracted coronary artery trees (CATs) from coronary computed tomography angiography imagescould contain incorrect extractions which require manual corrections before they can be used in clinical practice.A model-guided method for improving the extracted CAT is described to automatically detect potential incorrectextractions and improve them.MethodsThe proposed method is a coarse-to-fine approach. A coarse improvement is first applied on all vessels in theextracted CAT, and then a fine improvement is applied only on vessels with higher clinical significance. Basedupon a decision tree, the proposed method automatically and iteratively performs improvement operations for theentire extracted CAT until it meets the stop criteria. The improvement of the extraction quality obtained by theproposed method is measured using a scoring system. 18 datasets were used to determine optimal values for theparameters involved in the model-guided method and 122 datasets were used for evaluation.ResultsCompared to the initial automatic extractions, the proposed method improves the CATs for 122 datasets from anaverage quality score of 87±6 to 93±4. The developed method is able to run within 2 minutes on a typicalworkstation. The difference in extraction quality after automatic improvement is negatively correlated with theinitial extraction quality (R=-0.694, P<0.001).ConclusionWithout deteriorating the initially extracted CATs, the presented method automatically detects incorrectextractions and improves the CATs to an average quality score of 93 guided by anatomical statistical models. Show less
Cao, Q.; Broersen, A.; Graaf, M.A. de; Kitslaar, P.H.; Yang, G.Y.; Scholte, A.J.; ... ; Dijkstra, J. 2017
