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Distribution, size, and shape of abdominal aortic calcified deposits and their relationship to mortality in postmenopausal women.

Ganz M, de Bruijne M, Dam EB, Pettersen P, Karsdal MA, Christiansen C, Nielsen M - Int J Biomed Imaging (2012)

Bottom Line: Methods.Results.Morphometric markers of AAC quantified from radiographs may be a useful tool for screening and monitoring risk of CVD mortality.

View Article: PubMed Central - PubMed

Affiliation: Department of Computer Science, University of Copenhagen, 2100 Copenhagen, Denmark.

ABSTRACT
Abdominal aortic calcifications (AACs) correlate strongly with coronary artery calcifications and can be predictors of cardiovascular mortality. We investigated whether size, shape, and distribution of AACs are related to mortality and how such prognostic markers perform compared to the state-of-the-art AC24 marker introduced by Kauppila. Methods. For 308 postmenopausal women, we quantified the number of AAC and the percentage of the abdominal aorta that the lesions occupied in terms of their area, simulated plaque area, thickness, wall coverage, and length. We analysed inter-/intraobserver reproducibility and predictive ability of mortality after 8-9 years via Cox regression leading to hazard ratios (HRs). Results. The coefficient of variation was below 25% for all markers. The strongest individual predictors were the number of calcifications (HR = 2.4) and the simulated area percentage (HR = 2.96) of a calcified plaque, and, unlike AC24 (HR = 1.66), they allowed mortality prediction also after adjusting for traditional risk factors. In a combined Cox regression model, the strongest complementary predictors were the number of calcifications (HR = 2.76) and the area percentage (HR = -3.84). Conclusion. Morphometric markers of AAC quantified from radiographs may be a useful tool for screening and monitoring risk of CVD mortality.

No MeSH data available.


Related in: MedlinePlus

Left: a schematic visualization of a plaque similar to what can be seen in histology. The calcified plaque (light blue) is surrounded by an area of necrotic tissue (gray). Right: the simulated area tries to imitate the area of necrotic tissue (green) as seen in histology by a morphological dilation (visualized by circles) of the calcified plaque (light blue).
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fig3: Left: a schematic visualization of a plaque similar to what can be seen in histology. The calcified plaque (light blue) is surrounded by an area of necrotic tissue (gray). Right: the simulated area tries to imitate the area of necrotic tissue (green) as seen in histology by a morphological dilation (visualized by circles) of the calcified plaque (light blue).

Mentions: Simulated area percentage: we tried to estimate the size of the underlying atherosclerotic inflammation from the area and shape of the observed AACs since X-ray analysis can only visualize the calcified core of the AACs. The extent of the atherosclerotic inflammation was simulated by a morphological dilation [22] with a circular structuring element of radius 200 pixels (approximately 8.9 mm). The size of the structuring element was derived by a parameter study on a subset of the data, and it was confirmed to be biologically sensible by comparing with histology and image analysis observations which estimated the size of the atherosclerotic inflammation surrounding the calcified plaque to be between 3 mm [23] and 5–10 mm [24]. An illustration of this computer-based simulation of the full plaque area is given in Figure 3. The simulated area percentage is the percentage of the lumbar aorta covered by the simulated plaques including both calcified core and simulated inflamed area.


Distribution, size, and shape of abdominal aortic calcified deposits and their relationship to mortality in postmenopausal women.

Ganz M, de Bruijne M, Dam EB, Pettersen P, Karsdal MA, Christiansen C, Nielsen M - Int J Biomed Imaging (2012)

Left: a schematic visualization of a plaque similar to what can be seen in histology. The calcified plaque (light blue) is surrounded by an area of necrotic tissue (gray). Right: the simulated area tries to imitate the area of necrotic tissue (green) as seen in histology by a morphological dilation (visualized by circles) of the calcified plaque (light blue).
© Copyright Policy - open-access
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC3375152&req=5

fig3: Left: a schematic visualization of a plaque similar to what can be seen in histology. The calcified plaque (light blue) is surrounded by an area of necrotic tissue (gray). Right: the simulated area tries to imitate the area of necrotic tissue (green) as seen in histology by a morphological dilation (visualized by circles) of the calcified plaque (light blue).
Mentions: Simulated area percentage: we tried to estimate the size of the underlying atherosclerotic inflammation from the area and shape of the observed AACs since X-ray analysis can only visualize the calcified core of the AACs. The extent of the atherosclerotic inflammation was simulated by a morphological dilation [22] with a circular structuring element of radius 200 pixels (approximately 8.9 mm). The size of the structuring element was derived by a parameter study on a subset of the data, and it was confirmed to be biologically sensible by comparing with histology and image analysis observations which estimated the size of the atherosclerotic inflammation surrounding the calcified plaque to be between 3 mm [23] and 5–10 mm [24]. An illustration of this computer-based simulation of the full plaque area is given in Figure 3. The simulated area percentage is the percentage of the lumbar aorta covered by the simulated plaques including both calcified core and simulated inflamed area.

Bottom Line: Methods.Results.Morphometric markers of AAC quantified from radiographs may be a useful tool for screening and monitoring risk of CVD mortality.

View Article: PubMed Central - PubMed

Affiliation: Department of Computer Science, University of Copenhagen, 2100 Copenhagen, Denmark.

ABSTRACT
Abdominal aortic calcifications (AACs) correlate strongly with coronary artery calcifications and can be predictors of cardiovascular mortality. We investigated whether size, shape, and distribution of AACs are related to mortality and how such prognostic markers perform compared to the state-of-the-art AC24 marker introduced by Kauppila. Methods. For 308 postmenopausal women, we quantified the number of AAC and the percentage of the abdominal aorta that the lesions occupied in terms of their area, simulated plaque area, thickness, wall coverage, and length. We analysed inter-/intraobserver reproducibility and predictive ability of mortality after 8-9 years via Cox regression leading to hazard ratios (HRs). Results. The coefficient of variation was below 25% for all markers. The strongest individual predictors were the number of calcifications (HR = 2.4) and the simulated area percentage (HR = 2.96) of a calcified plaque, and, unlike AC24 (HR = 1.66), they allowed mortality prediction also after adjusting for traditional risk factors. In a combined Cox regression model, the strongest complementary predictors were the number of calcifications (HR = 2.76) and the area percentage (HR = -3.84). Conclusion. Morphometric markers of AAC quantified from radiographs may be a useful tool for screening and monitoring risk of CVD mortality.

No MeSH data available.


Related in: MedlinePlus