Prenatal Echocardiography in Three and Four Dimensions
- 4D colour Doppler flow imaging & complex cardiac defect detection
Read Display Info if you have difficulty browsing these graphics-orientated pages.To view a movie, click on an image with a [GIF] or [AVI] link)
Red & blue in the left image show flows towards & away from the probe located ‘behind’ this page. The red indicates flows from the superior and inferior vena cava (SVC, IVC) returning to the right atrium (RA), with partial flow through the oval foramen (OF) into the left atrium (LA). The blues are systolic flows from the right and left ventricular outlets (RVo, LVo) into the pulmonary trunk (PT) and ascending aorta (AAO, mostly obscured by the red), correspondingly. The blues in the two ventricles appear to merge along the dotted line due to colour smearing artefacts, which are inherited from cross-sectional ultrasound and need to be overcome. 
The 4D intracardiovascular flow from a 32-week fetal heart is viewed left-inferio-posteriorly. Click here [AVI 77KB] to see a movie of the flow without showing the heart. Click here [AVI 444KB] to see a movie of the same flow running through the heart.
DORV diastolic movie, GIF 307KB
ToF systolic movie, GIF 343KB
The unique dynamic diagnostic potential of the 4D echocardiography for prenatal detection of the complex cardiac defects. The above two images are reconstructed from a 4D dataset created using both grey-scale and colour Doppler information from a 22-week fetus. The structures are coloured according to anatomy (not flow direction). The movie linked from the diastolic image [GIF 307KB] shows that both the ascending aorta (AAO) and pulmonary trunk (PT, behind the AAO) arise exclusively from the right ventricle (RV, white arrow), i.e., double-outlet right ventricle (DORV). This was consistent with cross-sectional findings. Because they are diastolic views when blood flow in the AAO and PT is slow, narrow flow paths imaged. The movie linked from the systolic image [GIF 343KB] shows wider paths due to rapid systolic flow. Note that the shunting flow from the left ventricule (LV) through the ventricular septal defect (black arrow) reveals the overriding of the aorta, only seen in systole, with the narrowed PT. The overall diagnosis is then tetralogy of Fallot, with associated DORV. Arch: aortic arch; PV: pulmonary vein; RA: right atrium.