Limits...
Changes in Cross-Sectional Area and Transverse Diameter of the Heart on Inspiratory and Expiratory Chest CT: Correlation with Changes in Lung Size and Influence on Cardiothoracic Ratio Measurement.

Tomita H, Yamashiro T, Matsuoka S, Matsushita S, Kurihara Y, Nakajima Y - PLoS ONE (2015)

Bottom Line: Significant negative correlations were found between the E/I ratios of these cardiac measurements and the E/I ratios of lung volume and vertical lung diameter (p < 0.01).CT-based CTR was significantly larger on expiration than on inspiration (p < 0.0001).The CTR is also significantly influenced by ventilation.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology, St. Marianna University School of Medicine, Kawasaki, Kanagawa, Japan.

ABSTRACT

Objective: The aim of this study was to investigate physiological changes in cardiac area and diameters between inspiratory and expiratory chest computed tomography (CT), and to assess their correlation with lung size change and influence on cardiothoracic ratio (CTR) measurements.

Materials and methods: The institutional review board of our institution approved this study, and informed consent was waived. Forty-three subjects underwent inspiratory and expiratory chest CT as part of routine clinical care. On both inspiratory and expiratory scans, lung volumes and maximum lung diameters (transverse and vertical directions) were measured. The maximum cardiac cross-sectional area (CSA) and the maximum transverse cardiac diameter were measured on both scans, and the CT-based CTR was calculated. Changes in the lung and cardiac measurements were expressed as the expiratory/inspiratory (E/I) ratios. Comparisons between inspiratory and expiratory measurements were made by the Wilcoxon signed-rank test. Correlations between the E/I ratios of lung and heart measurements were evaluated by Spearman's rank correlation analysis.

Results: Cardiac CSA and transverse cardiac diameter was significantly larger on expiratory than on inspiratory CT (p < 0.0001). Significant negative correlations were found between the E/I ratios of these cardiac measurements and the E/I ratios of lung volume and vertical lung diameter (p < 0.01). CT-based CTR was significantly larger on expiration than on inspiration (p < 0.0001).

Conclusions: Heart size on chest CT depends on the phase of ventilation, and is correlated with changes in lung volume and craniocaudal lung diameter. The CTR is also significantly influenced by ventilation.

No MeSH data available.


Related in: MedlinePlus

54-year-old male with COPD.The method for measuring cardiac cross-sectional area (CSA) is shown. A CT image with the maximum cardiac CSA was initially selected (A). The targeted cardiac area was extracted on the image using a threshold setting (B, from 0 to 300 Hounsfield units) to exclude the pericardial fat pad. Black spots included in the cardiac area are fat tissue or artifacts. The cardiac CSA was measured using another threshold setting (C, from -100 to 300 Hounsfield units) to include the black spots excluded on the former image.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4494711&req=5

pone.0131902.g001: 54-year-old male with COPD.The method for measuring cardiac cross-sectional area (CSA) is shown. A CT image with the maximum cardiac CSA was initially selected (A). The targeted cardiac area was extracted on the image using a threshold setting (B, from 0 to 300 Hounsfield units) to exclude the pericardial fat pad. Black spots included in the cardiac area are fat tissue or artifacts. The cardiac CSA was measured using another threshold setting (C, from -100 to 300 Hounsfield units) to include the black spots excluded on the former image.

Mentions: Cardiac cross-sectional areas (CSA) on CT were semi-automatically measured using open-source software (Image J, version 1.47, Bethesda, MD, USA). In brief, the following process was performed for the measurements (Fig 1): (1) we selected a CT slice that demonstrated the maximum cardiac CSA, which was usually near the diaphragmatic apex; (2) the cardiac boundary was determined by a threshold setting using Hounsfield units (HU) to exclude the pericardial fat pad (from 0 to 300 HU); (3) the targeted cardiac area was extracted using the determined boundary; and (4) cardiac CSA was automatically measured using another threshold setting (from -100 to 300 HU), which included fat tissues or low density artifacts inside the heart. This whole process required approximately three minutes for each CT scan.


Changes in Cross-Sectional Area and Transverse Diameter of the Heart on Inspiratory and Expiratory Chest CT: Correlation with Changes in Lung Size and Influence on Cardiothoracic Ratio Measurement.

Tomita H, Yamashiro T, Matsuoka S, Matsushita S, Kurihara Y, Nakajima Y - PLoS ONE (2015)

54-year-old male with COPD.The method for measuring cardiac cross-sectional area (CSA) is shown. A CT image with the maximum cardiac CSA was initially selected (A). The targeted cardiac area was extracted on the image using a threshold setting (B, from 0 to 300 Hounsfield units) to exclude the pericardial fat pad. Black spots included in the cardiac area are fat tissue or artifacts. The cardiac CSA was measured using another threshold setting (C, from -100 to 300 Hounsfield units) to include the black spots excluded on the former image.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4494711&req=5

pone.0131902.g001: 54-year-old male with COPD.The method for measuring cardiac cross-sectional area (CSA) is shown. A CT image with the maximum cardiac CSA was initially selected (A). The targeted cardiac area was extracted on the image using a threshold setting (B, from 0 to 300 Hounsfield units) to exclude the pericardial fat pad. Black spots included in the cardiac area are fat tissue or artifacts. The cardiac CSA was measured using another threshold setting (C, from -100 to 300 Hounsfield units) to include the black spots excluded on the former image.
Mentions: Cardiac cross-sectional areas (CSA) on CT were semi-automatically measured using open-source software (Image J, version 1.47, Bethesda, MD, USA). In brief, the following process was performed for the measurements (Fig 1): (1) we selected a CT slice that demonstrated the maximum cardiac CSA, which was usually near the diaphragmatic apex; (2) the cardiac boundary was determined by a threshold setting using Hounsfield units (HU) to exclude the pericardial fat pad (from 0 to 300 HU); (3) the targeted cardiac area was extracted using the determined boundary; and (4) cardiac CSA was automatically measured using another threshold setting (from -100 to 300 HU), which included fat tissues or low density artifacts inside the heart. This whole process required approximately three minutes for each CT scan.

Bottom Line: Significant negative correlations were found between the E/I ratios of these cardiac measurements and the E/I ratios of lung volume and vertical lung diameter (p < 0.01).CT-based CTR was significantly larger on expiration than on inspiration (p < 0.0001).The CTR is also significantly influenced by ventilation.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology, St. Marianna University School of Medicine, Kawasaki, Kanagawa, Japan.

ABSTRACT

Objective: The aim of this study was to investigate physiological changes in cardiac area and diameters between inspiratory and expiratory chest computed tomography (CT), and to assess their correlation with lung size change and influence on cardiothoracic ratio (CTR) measurements.

Materials and methods: The institutional review board of our institution approved this study, and informed consent was waived. Forty-three subjects underwent inspiratory and expiratory chest CT as part of routine clinical care. On both inspiratory and expiratory scans, lung volumes and maximum lung diameters (transverse and vertical directions) were measured. The maximum cardiac cross-sectional area (CSA) and the maximum transverse cardiac diameter were measured on both scans, and the CT-based CTR was calculated. Changes in the lung and cardiac measurements were expressed as the expiratory/inspiratory (E/I) ratios. Comparisons between inspiratory and expiratory measurements were made by the Wilcoxon signed-rank test. Correlations between the E/I ratios of lung and heart measurements were evaluated by Spearman's rank correlation analysis.

Results: Cardiac CSA and transverse cardiac diameter was significantly larger on expiratory than on inspiratory CT (p < 0.0001). Significant negative correlations were found between the E/I ratios of these cardiac measurements and the E/I ratios of lung volume and vertical lung diameter (p < 0.01). CT-based CTR was significantly larger on expiration than on inspiration (p < 0.0001).

Conclusions: Heart size on chest CT depends on the phase of ventilation, and is correlated with changes in lung volume and craniocaudal lung diameter. The CTR is also significantly influenced by ventilation.

No MeSH data available.


Related in: MedlinePlus