Pediatric Cardiothoracic CT Guideline Provided by the Asian Society of Cardiovascular Imaging Congenital Heart Disease Study Group: Part 2. Contemporary Clinical Applications

Pediatric three-dimensional quantitative cardiovascular computed tomography

High-resolution, isotropic, 3-dimensional (D) data from pediatric cardiovascular computed tomography (CT) offer great potential for the accurate quantitative evaluation of pediatric cardiovascular and pulmonary vascular diseases. Recent pilot studies using pediatric 3-D cardiovascular CT have shown promising results in assessing cardiac function in conditions such as tetralogy of Fallot, cardiac defects with a hypoplastic ventricle, Ebstein anomaly, and in quantifying myocardial mass. In addition, the quantitative assessment of pulmonary vascularity is useful for evaluating differential right-to-left pulmonary vascular volume ratio, the effectiveness of pulmonary angioplasty, and predicting pulmonary hypertension. These initial experiences could broaden the role of pediatric cardiovascular CT in clinical practice. Furthermore, the current barriers to its widespread use, pertinent solutions to these problems, and new applications are discussed. In this review, the 3-D quantitative evaluations of cardiac function and pulmonary vascularity using high-resolution pediatric cardiovascular CT data are illustrated.

Impact of beam collimation of z-overscanning on dose to the lens and thyroid gland in paediatric thoracic computed tomography imaging

BACKGROUND

Adaptive collimation reduces the dose deposited outside the imaged volume along the z-axis. An increase in the dose deposited outside the imaged volume (to the lens and thyroid) in the z-axis direction is a concern in paediatric computed tomography (CT).

OBJECTIVE

To compare the dose deposited outside the imaged volume (to the lens and thyroid) between 40-mm and 80-mm collimation during thoracic paediatric helical CT.

MATERIALS AND METHODS

We used anthropomorphic phantoms of newborns and 5-year-olds with 40-mm and 80-mm collimation during helical CT. We compared the measured dose deposited outside the imaged volume using optically stimulated luminescence dosimeters (OSLD) at the surfaces of the lens and thyroid and the image noise between the 40-mm and 80-mm collimations.

RESULTS

There were significant differences in the dose deposited outside the imaged volume (to the lens and thyroid) between the 40-mm and 80-mm collimations for both phantoms (P < 0.01).

CONCLUSION

Compared with that observed for 80-mm collimation in helical CT scans of the paediatric thorax, the dose deposited outside the imaged volume (to the lens and thyroid) was significantly lower in newborns and 5-year-olds with 40-mm collimation.

Cardiac Computed Tomography in Congenital Heart Disease

Computed tomography (CT) has emerged as a leading imaging modality in the evaluation of congenital heart disease (CHD). With ever-faster acquisition speed, decreasing radiation exposure, impeccable anatomic detail, optional functional data, and numerous post-processing tools, CT offers broad utility in CHD diagnosis, preoperative planning, and postoperative assessment. In this article, the far-reaching role of CT in CHD is reviewed, focusing on technical imaging considerations and key clinical applications.

Trends in cardiac CT utilization for patients with pediatric and congenital heart disease: A multicenter survey study

BACKGROUND

The use of cardiac CT (CCT) has increased dramatically in recent years among patients with pediatric and congenital heart disease (CHD), but little is known about trends and practice pattern variation in CCT utilization for this population among centers.

METHODS

A 21-item survey was created to assess CCT utilization in the pediatric/CHD population in calendar years 2011 and 2021. The survey was sent to all non-invasive cardiac imaging directors of pediatric cardiology centers in North America in September 2022.

RESULTS

Forty-one centers completed the survey. In 2021, 98% of centers performed CCT in pediatric and CHD patients (vs. 73% in 2011), and 61% of centers performed >100 CCTs annually (vs. 5% in 2011). While 62% of centers in 2021 utilized dual-source technology for high-pitch helical acquisition, 15% of centers reported primarily performing CCT on a 64-slice scanner. Anesthesia utilization, use of medications for heart rate control, and type of subspecialty training for physicians interpreting CCT varied widely among centers. 50% of centers reported barriers to CCT performance, with the most commonly cited concerns being radiation exposure, the need for anesthesia, and limited CT scan staffing or machine access. 37% (11/30) of centers with a pediatric cardiology fellowship program offer no clinical or didactic CCT training for categorical fellows.

CONCLUSION

While CCT usage in the CHD/pediatric population has risen significantly in the past decade, there is broad center variability in CCT acquisition techniques, staffing, workflow, and utilization. Potential areas for improvement include expanding CT scanner access and staffing, formal CCT education for pediatric cardiology fellows, and increasing utilization of existing technological advances.

Computed tomography angiography features of children with ectopia cordis

Ectopia cordis is a rare congenital defect with high mortality, and it remains challenging to radiologists, neonatologists and surgeons. CT angiography provides key information that aids in the decision-making process for possible surgical intervention. This pictorial essay describes CT angiography features in six neonates with ectopia cordis.

The combination of conventional ultrasound and shear-wave elastography in evaluating the segmental heterogeneity of liver fibrosis in biliary atresia patients after Kasai portoenterostomy

OBJECTIVE

To retrospectively assess the value of the combination of conventional ultrasound and shear-wave elastography (SWE) in evaluating the segmental heterogeneity of liver fibrosis in biliary atresia (BA) patients after Kasai portoenterostomy.

METHODS

A total of 35 BA patients with liver segmental deformation were enrolled. The segmental deformation was assessed by conventional ultrasound followed with SWE examinations for evaluating the liver stiffness. Liver biopsy was performed in 11 patients in the region of SWE measurement and liver fibrosis was assessed using the Metavir classification. Aminotransferase to platelet ratio index (APRI) was calculated for comparison. The correlations between serum biochemical tests with SWE values were evaluated. Spearman's rank coefficient test was performed to evaluate the correlation between variables.

RESULTS

The SWE values of the biopsy segments had significant positive correlations with liver fibrosis severity (r = 0.828, p = 0.001), which was better than APRI (r = 0.366, p = 0.242). The levels of bilirubin and transaminase showed significant correlations with the SWE values at hypertrophic segments in all patients (r from 0.336 to 0.576, all p < 0.05).

CONCLUSIONS

Awareness of the segmental heterogeneity of liver fibrosis evaluated by conventional ultrasound and SWE may assist in selecting an appropriate biopsy location and predicting postoperative surveillance for patients with BA.