From hand-rotated multiplane transesophageal to fast rotating parasternal probes for cardiac imaging.

(T) under bar rans-(E) under bar sophageal (E) under bar chocardiographic (TEE) probes were introduced around 1982. The development ranges over the years from single plane, phased array transducers at low frequency to today's multiplane probes with a large number of elements. Further miniaturisation and higher frequencies allow paediatric application. Recent development includes a probe with 48 elements at 7 MHz with a shaft diameter of only 5 mm, TEE multiplane probes have from the beginning been used for three-dimensional (3D) data acquisition. The same technique can be used with (T) under bar rans-(T) under bar horacic (E) under bar chocardiography (TTE) transducers placed on the thorax. A large number of cross-sectional two-dimensional scans have to be acquired sequentially before a 3D image can be reconstructed. Acquisition is done step by step based on ECG triggering plus respiratory gating to limit motion artifacts. In this lecture, a fast continuously rotating scanning unit with a 64-element phased array transducer will be introduced together with the first clinical data. This 3D unit generates sixteen volumes of echo data per second in real time. This project is supported by the Dutch Technology Foundation, project RGN 44.3322.