3D/4D hybrid spectral domain synthetic aperture image reconstruction method for hand-held ultrasound systems

In the last few decades 3D/4D ultrasonography has been gaining increasing popularity not only as a scientific research topic but also as a new modality of medical imaging in clinical applications. However, design and implementation of 3D/4D device for high quality ultrasound imaging within portable, handheld systems is a technological challenge. Design of transmit/receive (TX/RX) electronics for efficient operation with 2D array transducers, comprised of thousands of elements, enormous amount of input/output data that must be transferred and processed, power consumption limitation are just a few of the difficulties that arise. No less important is development of reliable and numerically efficient algorithms for 3D/4D imaging which should take all these restrictions into account. The main objective of this paper is to present a new hybrid spectral domain imaging (HSDI) method that delivers an original and innovative solution for the technical limitations of modern ultrasonography 3D/4D. The developed image reconstruction method is based on the plane-wave insonification (PWI) with sub-aperture data acquisition combined with frequency domain (FD) data processing. The performance of the method was tested using the Field II simulated acoustic data of 3D cyst phantom. For a 3D low-resolution image (LRI) comprised of 64×64×512 pixels the proposed HSDI method is about 100 times faster, in the case of a single 3D, than its counterpart based on the PWI synthetic aperture time domain (TD) method for a single TX/RX event. On the other hand, the frame rate increase is proportional to the number of sub-apertures used for a single high-resolution image (HRI) synthesis.