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Paediatric multi-detector row chest CT: what you really need to know.

Young C, Xie C, Owens CM - Insights Imaging (2012)

Bottom Line: Paediatric imaging technique/protocol together with radiation dose reduction is discussed in detail.However, users must be vigilant in their imaging techniques to minimise radiation burden, whilst maintaining good image quality.Main Messages • CT examinations should be clinically justified by the referring clinician and radiologist. • MDCT is invaluable for evaluating the central airway, mediastinal structures and lung parenchyma. • MDCT is more sensitive than plain radiographs in detection of structural changes within the lungs.

View Article: PubMed Central - PubMed

Affiliation: Cardio-thoracic Unit, Great Ormond Street Hospital for Children NHS Trust, London, WC1N, 3JH, UK, carolyn.young16@yahoo.co.uk.

ABSTRACT

Background: The emergence of multi-detector row CT (MDCT) has established and extended the role of CT especially in paediatric chest imaging. This has altered the way in which data is acquired and is perceived as the 'gold standard' in the detection of certain chest pathologies. The range of available post-processing tools provide alternative ways in which CT images can be manipulated for review and interpretation in order to enhance diagnostic accuracy.

Methodology: Paediatric imaging technique/protocol together with radiation dose reduction is discussed in detail. The use of different post-processing tools to best demonstrate the wide range of important congenital anomalies and thoracic pathologies is outlined and presented pictorially.

Conclusion: MDCT with its isotropic resolution and fast imaging acquisition times reduces the need for invasive diagnostic investigations. However, users must be vigilant in their imaging techniques to minimise radiation burden, whilst maintaining good image quality. Main Messages • CT examinations should be clinically justified by the referring clinician and radiologist. • MDCT is invaluable for evaluating the central airway, mediastinal structures and lung parenchyma. • MDCT is more sensitive than plain radiographs in detection of structural changes within the lungs.

No MeSH data available.


Related in: MedlinePlus

The position of the ascending aorta or pulmonary artery cannot be distinguished on this axial pre-monitoring image (a) in a 1-month-old child with a large thymus and lack of mediastinal body fat, making it difficult to accurately place the ROI for automatic scan triggering. Post contrast enhancement positions of the great vessels are clearly seen in b. Scanning parameters: 80 kV, 10 mAs
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Fig2: The position of the ascending aorta or pulmonary artery cannot be distinguished on this axial pre-monitoring image (a) in a 1-month-old child with a large thymus and lack of mediastinal body fat, making it difficult to accurately place the ROI for automatic scan triggering. Post contrast enhancement positions of the great vessels are clearly seen in b. Scanning parameters: 80 kV, 10 mAs

Mentions: The scan initiation time post injection differs with different imaging protocols. If contrast is delivered via a pressure injector, either a fixed scan delay of 20–30 sec is found to provide good anatomical enhancement or the scan delay can be timed to correspond to the end of the contrast and saline delivery. For hand injection, the scan starts at the end of the injection. In angiographic studies, a visual bolus tracking method is used in younger children, whereby the scan is initiated by the operator when contrast is seen in the pre-determined target area on the low dose monitoring slices, with the scan region of interest (ROI) placed outside the patient to disable the automated trigger. This is due to difficulty in discerning where to place the ROI on the image, as children have relatively little fat between thoracic structures hence a very bland mediastinum (Fig. 2). An automated bolus tracking method can be used in older children. The ROI is placed at different sites to ensure maximum enhancement of the anatomical structure in question, namely the ascending aorta for aortic enhancement, the main pulmonary artery for delineating the pulmonary arteries, and the left atrium for demonstrating the pulmonary veins. The scan is triggered automatically when the contrast in these vessels reaches +100 Hounsfield units (HU).Fig. 2


Paediatric multi-detector row chest CT: what you really need to know.

Young C, Xie C, Owens CM - Insights Imaging (2012)

The position of the ascending aorta or pulmonary artery cannot be distinguished on this axial pre-monitoring image (a) in a 1-month-old child with a large thymus and lack of mediastinal body fat, making it difficult to accurately place the ROI for automatic scan triggering. Post contrast enhancement positions of the great vessels are clearly seen in b. Scanning parameters: 80 kV, 10 mAs
© Copyright Policy
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC3369117&req=5

Fig2: The position of the ascending aorta or pulmonary artery cannot be distinguished on this axial pre-monitoring image (a) in a 1-month-old child with a large thymus and lack of mediastinal body fat, making it difficult to accurately place the ROI for automatic scan triggering. Post contrast enhancement positions of the great vessels are clearly seen in b. Scanning parameters: 80 kV, 10 mAs
Mentions: The scan initiation time post injection differs with different imaging protocols. If contrast is delivered via a pressure injector, either a fixed scan delay of 20–30 sec is found to provide good anatomical enhancement or the scan delay can be timed to correspond to the end of the contrast and saline delivery. For hand injection, the scan starts at the end of the injection. In angiographic studies, a visual bolus tracking method is used in younger children, whereby the scan is initiated by the operator when contrast is seen in the pre-determined target area on the low dose monitoring slices, with the scan region of interest (ROI) placed outside the patient to disable the automated trigger. This is due to difficulty in discerning where to place the ROI on the image, as children have relatively little fat between thoracic structures hence a very bland mediastinum (Fig. 2). An automated bolus tracking method can be used in older children. The ROI is placed at different sites to ensure maximum enhancement of the anatomical structure in question, namely the ascending aorta for aortic enhancement, the main pulmonary artery for delineating the pulmonary arteries, and the left atrium for demonstrating the pulmonary veins. The scan is triggered automatically when the contrast in these vessels reaches +100 Hounsfield units (HU).Fig. 2

Bottom Line: Paediatric imaging technique/protocol together with radiation dose reduction is discussed in detail.However, users must be vigilant in their imaging techniques to minimise radiation burden, whilst maintaining good image quality.Main Messages • CT examinations should be clinically justified by the referring clinician and radiologist. • MDCT is invaluable for evaluating the central airway, mediastinal structures and lung parenchyma. • MDCT is more sensitive than plain radiographs in detection of structural changes within the lungs.

View Article: PubMed Central - PubMed

Affiliation: Cardio-thoracic Unit, Great Ormond Street Hospital for Children NHS Trust, London, WC1N, 3JH, UK, carolyn.young16@yahoo.co.uk.

ABSTRACT

Background: The emergence of multi-detector row CT (MDCT) has established and extended the role of CT especially in paediatric chest imaging. This has altered the way in which data is acquired and is perceived as the 'gold standard' in the detection of certain chest pathologies. The range of available post-processing tools provide alternative ways in which CT images can be manipulated for review and interpretation in order to enhance diagnostic accuracy.

Methodology: Paediatric imaging technique/protocol together with radiation dose reduction is discussed in detail. The use of different post-processing tools to best demonstrate the wide range of important congenital anomalies and thoracic pathologies is outlined and presented pictorially.

Conclusion: MDCT with its isotropic resolution and fast imaging acquisition times reduces the need for invasive diagnostic investigations. However, users must be vigilant in their imaging techniques to minimise radiation burden, whilst maintaining good image quality. Main Messages • CT examinations should be clinically justified by the referring clinician and radiologist. • MDCT is invaluable for evaluating the central airway, mediastinal structures and lung parenchyma. • MDCT is more sensitive than plain radiographs in detection of structural changes within the lungs.

No MeSH data available.


Related in: MedlinePlus