Paediatric multidetector CT angiography: spectrum of congenital thoracic vascular anomalies

[Contribution of cardiac CT in the management of congenital heart disease : experience of the Abidjan cardiology institute in 27 cases]

INTRODUCTION AND OBJECTIVES

In contrast to developed countries, cardiac CT is not widely used in West Africa for the assessment of congenital heart disease, and has only recently been introduced in Côte d'Ivoire. The lack of data prompted this study, the aim of which was to describe our experience of the contribution of CT to the management of congenital heart disease in the Ivorian cardiology setting.

PATIENTS AND METHOD

This was a prospective study which took place in the pediatric cardiology department over a period of 9 months (September 2022 to June 2023) which included all patients with congenital heart disease explored by echocardiography and cardiac scan.

RESULTS

The average age was 5.7 ± 4.7 years with extremes of 5 months and 16 years. We noted a female predominance with a sex ratio of 0.52. The main heart diseases were: tetralogy of Fallot (37.1%), followed by pulmonary atresia with open septum (18.52%). The assessment of the anatomy of the pulmonary arteries (81.48%), the search for aortopulmonary collaterals (59.63%) and finally the assessment of the anatomy of the aorta (18.52%) were the main indications. The practice of cardiac CT scanning has enabled better accuracy in the diagnosis and management of congenital heart disease in several cases: an interruption of the aortic arch was found in 1 case initially suspected of hypoplasia of the aortic arch, three cases of partial abnormal pulmonary venous return and one case of total abnormal pulmonary venous return. Also, agenesis of the left pulmonary artery with birth anomaly of the right coronary artery in the assessment of tetralogy of Fallot was found in 1 case. The CT scan made it possible to specify the exact topography of the aortopulmonary collaterals in four cases of pulmonary atresia with an open septum.

CONCLUSION

CT has enabled better visualization of the arterial and venous pulmonary tree, identification and exact localization of aorto-pulmonary collaterals, precise description of the three-dimensional anatomy of the coronary arteries, and better precision of congenital anomalies of the aorta.

[The contribution of multicut scanner use in arches and of the aortic arch anomalies in children]

Congenital malformations of the aortic arches are a heterogeneous group of diseases associated with developmental disorders of the primitive branchial arches during fetal life. The coarctation of the aorta is a common congenital vascular malformation which is a congenital narrowing of the aortic isthmus, a segment of the aorta between the left subclavian artery and the ductus arteriosus. The interruption of the aortic arch is considered by some authors as an extreme coarctation of the aorta, characterized by discontinuity between ascending and descending aorta. These abnormalities are integrated, in most cases, in the context of cardiac malformations from which they are indivisible. CT angiogram plays an essential role in the examination of these abnormalities, their preoperative assessment and their follow-up in the long term. We conducted a retrospective study of 42 patients undergoing CT angiogram following the detection of heart disease on echocardiography. CT angiogram was performed in 6 cases. The average age of patients was 2 years, ranging from 6 days to 14 years; a male predominance was reported with a sex ratio of 1,6. The main diseases were: coarctation of the aorta: 18 cases; hypoplasies of the aortic arch: 8 cases; interruptions of the aortic arch: 7 cases; abnormalities of the aortic arches: 9 cases. Some of these abnormalities were associated. Extracardiac abnormalities associated with congenital heart diseases are relatively frequent; multislice scanner allows for good analysis of the cardiac afferent and efferent pathways. CT complements echocardiogram for pre-treatment assessment of the main malformative diseases, especially for the detection of the associated extra-cardiac vascular abnormalities, thanks to its satisfactory tridimensional multiplanar exploration. It tends to supplant angiography in many pathological malformations for several reasons: it is less invasive; it provides high-resolution 3D images useful to surgeons; it established the anatomical diagnosis, assesses tracheal compression and any associated malformation; it guides surgical treatment.

Application of prospective ECG-gated high-pitch 128-slice dual-source CT angiography in the diagnosis of congenital extracardiac vascular anomalies in infants and children

PURPOSE

To investigate the value of prospective ECG-gated high-pitch 128-slice dual-source CT (DSCT) angiography in the diagnosis of congenital extracardiac vascular anomalies in infants and children in comparison with transthoracic echocardiography (TTE).

METHODS

Eighty consecutive infants or children clinically diagnosed of congenital heart disease and suspected with extracardiac vascular anomaly were enrolled, and 75 patients were finally included in this prospective study. All patients underwent prospective ECG-gated high-pitch DSCT angiography after TTE with an interval of 1-7 days. The diagnostic accuracy and sensitivity of high-pitch DSCT angiography and TTE were compared according to the surgical/CCA findings. The image quality of DSCT was assessed using a five-point scale. The effective radiation dose (ED) was calculated.

RESULTS

A total of 17 congenital heart diseases and 162 separate extracardiac vascular anomalies were confirmed by surgical/CCA findings in 75 patients. The diagnostic accuracy of high-pitch DSCT angiography and TTE was 99.67% and 97.89%, respectively. The sensitivity of high-pitch DSCT angiography and TTE was 97.53% and 79.62%, respectively. There was significant difference regarding to the diagnostic accuracy and the sensitivity between high-pitch DSCT angiography and TTE (χ2 = 23.561 and 28.013, P<0.05). The agreement on the image quality scoring of DSCT between the two observers was excellent (κ = 0.81), and the mean score of image quality was 4.1±0.7. The mean ED of DSCT was 0.29±0.08 mSv.

CONCLUSIONS

Prospective ECG-gated high-pitch 128-slice DSCT angiography with low radiation dose and high diagnostic accuracy has higher sensitivity compared to TTE in the detection of congenital extracardiac vascular anomalies in infants and children.

Proximal pulmonary vein stenosis detection in pediatric patients: value of multiplanar and 3-D VR imaging evaluation

BACKGROUND

One of the important benefits of using multidetector computed tomography (MDCT) is its capability to generate high-quality two-dimensional (2-D) multiplanar (MPR) and three-dimensional (3-D) images from volumetric and isotropic axial CT data. However, to the best of our knowledge, no results have been published on the potential diagnostic role of multiplanar and 3-D volume-rendered (VR) images in detecting pulmonary vein stenosis, a condition in which MDCT has recently assumed a role as the initial noninvasive imaging modality of choice.

OBJECTIVE

The purpose of this study was to compare diagnostic accuracy and interpretation time of axial, multiplanar and 3-D VR images for detection of proximal pulmonary vein stenosis in children, and to assess the potential added diagnostic value of multiplanar and 3-D VR images.

MATERIALS AND METHODS

We used our hospital information system to identify all consecutive children (< 18 years of age) with proximal pulmonary vein stenosis who had both a thoracic MDCT angiography study and a catheter-based conventional angiography within 2 months from June 2005 to February 2012. Two experienced pediatric radiologists independently reviewed each MDCT study for the presence of proximal pulmonary vein stenosis defined as ≥ 50% of luminal narrowing on axial, multiplanar and 3-D VR images. Final diagnosis was confirmed by angiographic findings. Diagnostic accuracy was compared using the z-test. Confidence level of diagnosis (scale 1-5, 5 = highest), perceived added diagnostic value (scale 1-5, 5 = highest), and interpretation time of multiplanar or 3-D VR images were compared using paired t-tests. Interobserver agreement was measured using the chance-corrected kappa coefficient.

RESULTS

The final study population consisted of 28 children (15 boys and 13 girls; mean age: 5.2 months). Diagnostic accuracy based on 116 individual pulmonary veins for detection of proximal pulmonary vein stenosis was 72.4% (84 of 116) for axial MDCT images, 77.5% (90 of 116 cases) for multiplanar MDCT images, and 93% (108 of 116 cases) for 3-D VR images with significantly higher accuracy with 3-D VR compared to axial (z = 4.17, P < 0.001) and multiplanar (z = 3.34, P < 0.001) images. Confidence levels for detection of proximal pulmonary vein stenosis were significantly higher with 3-D VR images (mean level: 4.6) compared to axial MDCT images (mean level: 1.7) and multiplanar MDCT images (mean level: 2.0) (paired t-tests, P < 0.001). Thus, 3-D VR images (mean added diagnostic value: 4.7) were found to provide added diagnostic value for detecting proximal pulmonary vein stenosis (paired t-test, P < 0.001); however, multiplanar MDCT images did not provide added value (paired t-test, P = 0.89). Interpretation time was significantly longer and interobserver agreement was higher when using 3-D VR images than using axial MDCT images or MPR MDCT images for diagnosing proximal pulmonary vein stenosis (paired t-tests, P < 0.001).

CONCLUSIONS

Use of 3-D VR images in the diagnosis of proximal pulmonary vein stenosis in children significantly increases accuracy, confidence level, added diagnostic value and interobserver agreement. Thus, the routine use of this technique should be encouraged despite its increased interpretation time.

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

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.

Multidetector computed tomography of pediatric large airway diseases: state-of-the-art

Advances in multidetector computed tomography (MDCT) technology have given rise to improvements in the noninvasive and comprehensive assessment of the large airways in pediatric patients. Superb two-dimensional and three-dimensional reconstruction MDCT images have revolutionized the display of large airways and enhanced the ability to diagnose large airway diseases in children. The 320-MDCT scanner, which provides combined detailed anatomic and dynamic functional information assessment of the large airways, is promising for the assessment of dynamic large airway disease such as tracheobronchomalacia. This article discusses imaging techniques and clinical applications of MDCT for assessing large airway diseases in pediatric patients.

Multidetector computed tomography and 3-dimensional imaging: preoperative evaluation of thoracic vascular and tracheobronchial anomalies and abnormalities in pediatric patients

In the past decade, rapid technical developments and advancements of multidetector computed tomography (MDCT) have revolutionized the preoperative imaging evaluation of thoracic vascular and tracheobronchial anomalies and abnormalities in infants and children. Multidetector computed tomography enables noninvasive, rapid, high-resolution, and 3-dimensional (3D) imaging of the thorax in pediatric patients that provides comprehensive preoperative surgical guidance for pediatric surgeons. With the increasing availability of MDCT and 3D imaging, a practical review is needed for the pediatric surgeon of the evolving role of these techniques in the preoperative evaluation of surgical lesions in infants and children. This article focuses on the review of advantages and disadvantages of MDCT in comparison to other imaging modalities, 2D and 3D imaging postprocessing techniques, and MDCT and 3D imaging appearance of various thoracic vascular and tracheobronchial anomalies and abnormalities in pediatric patients. The primary aim of this article was to facilitate the pediatric surgeons' ability to successfully incorporate MDCT and 3D imaging as a routine preoperative imaging tool for the evaluation of thoracic surgical lesions in infants and children.

Contrast-enhanced MR angiography of thoracic vascular malformations in children

To plan an effective management of thoracic vascular malformations, clinicians must have a clear understanding of the anatomy. Although echocardiography and angiography are the leading imaging modalities in patients with congenital cardiovascular anomalies, magnetic resonance (MR) imaging and computed tomography (CT) are valuable noninvasive adjuncts. MR imaging and CT are effective in demonstrating the complex extracardiac morphology and yield helpful information that can change the treatment plan. Although recent reports state the usefulness of multidetector CT (MDCT), in terms of pediatric population, the significance of radiation exposure should be taken into account. Thus, contrast enhanced MR angiography, as a guide in planning surgery, seems to be the best alternative to conventional angiography in the diagnosis of congenital vascular malformations. In this review, the diagnostic features of thoracic vascular malformations in pediatric population are discussed, and, the potential uses of contrast-enhanced MR angiography are emphasized with the retrospective evaluation of imaging findings in 114 examinations.