State-of-the-Art CT Imaging Techniques for Congenital Heart Disease

Abstract

CT is increasingly being used for evaluating the cardiovascular structures and airways in the patients with congenital heart disease. Multi-slice CT has traditionally been used for the evaluation of the extracardiac vascular and airway abnormalities because of its inherent high spatial resolution and excellent air-tissue contrast. Recent developments in CT technology primarily by reducing the cardiac motion and the radiation dose usage in congenital heart disease evaluation have helped expand the indications for CT usage. Tracheobronchomalacia associated with congenital heart disease can be evaluated with cine CT. Intravenous contrast injection should be tailored to unequivocally demonstrate cardiovascular abnormalities. Knowledge of the state-of-the-art CT imaging techniques that are used for evaluating congenital heart disease is helpful not only for planning and performing CT examinations, but also for interpreting and presenting the CT image findings that consequently guide the proper medical and surgical management.

Paediatric cardiac computed tomography: a review of imaging techniques and radiation dose consideration

“…The images demonstrate a systemic arterial supply (a) originating from the anterior aorta (located between the coeliac axis and SMA) with a large draining vein (b) connecting to the right inferior pulmonary vein. CTDIvol=0.61 mGy, effective dose=0.9 mSv still sufficient for functional analysis but a reduction to 4% may only be limited to imaging where gross overall anatomical evaluation is necessary [14]. Our experience is that the degree of dose reduction is heavily dependent on the applied CT parameters.…”

“…As with all spiral acquisitions in CT, there is an inevitable increase in radiation dose due to the longitudinal over-ranging at both ends of coverage [14]. This problem has been addressed by manufacturer with incorporation of adaptive dose shields to block radiation during the 'run-up' and 'run-down' time necessary for spiral data acquisition (Siemens Healthcare, Forchheim, Germany).…”

“…In children, the end systolic phase (where maximum tube current is applied) is preferred with HR above 80 bpm, [7,14,19,20] this being less susceptible to motion artefacts, (Fig. 7).…”

“…But the study was diagnostic demonstrating good filling of the pulmonary arteries from the BT shunt seen in the coronal images b & c and in the axial MIP image d. CTDIvol=1.33 mGy, effective dose=0.87 mSv and attenuation. When combined with ECG-controlled tube current modulation a dose reduction between 9% and 26% can be achieved [14]. However, Tsai et al [2] believe dose modulation is ineffective in neonates due to the short CT data acquisition and heterogeneous composition of the bones and soft tissues of the neonatal chest.…”

“…With the advent of dual-source (DSCT) technology (Siemens Definition, Forchheim, Germany) it is now feasible to extend ECG-synchronised cardiac imaging (utilising both retrospective and prospective gating) to the paediatric population even for non-coronary applications [13][14][15][16], (Fig. 1).…”