Ultrasound contrast agent imaging: Real-time imaging of the superharmonics

Currently, in medical ultrasound contrast agent (UCA) imaging the second harmonic scattering of the microbubbles is regularly used. This scattering is in competition with the signal that is caused by nonlinear wave propagation in tissue. It was reported that UCA imaging based on the third or higher harmonics, i.e. “superharmonic” imaging, shows...

Single pulse frequency compounding protocol for superharmonic imaging

Second harmonic imaging is currently adopted as standard in commercial echographic systems. A new imaging technique, coined as superharmonic imaging (SHI), combines the 3rd till the 5th harmonics, arising during nonlinear sound propagation. It could further enhance resolution and quality of echographic images. To meet the bandwidth requirement...

Developing a tool for the validation of quantitative DCE-MRI

Dynamic Contrast-Enhanced Magnetic Resonance Imaging (DCE-MRI) is becoming an indispensable tool to noninvasively study tumor characteristics. However, many different DCE-analysis methods are currently being used. To compare and validate different methods, histology is the gold standard. For this purpose, exact co-localization between histology...

Feasibility study of superharmonic imaging using chirps

Superharmonic imaging (SHI) targets a combination of the 3rd to 5th harmonics. It was proven to have certain advantages in comparison with the established imaging standards in medical utrasound. SHI enhances the spatial resolution and improves the quality of echographic images, mainly by eliminating reverberation artifacts at the chest wall....

Multi-modal image registration: Matching MRI with histology

Computation of three-dimensional, pulsed, nonlinear acoustic wavefields from medical phased array transducers in very large domains

For the optimization and development of medical ultrasound transducers and imaging modalities, the Iterative Nonlinear Contrast Source (INCS) method has been developed. This numerical method predicts the nonlinear acoustic pressure field, generated by a pulsed, plane source with an arbitrary aperture, and propagating in a three-dimensional...

Performance of the flight model HIFI band 3 and 4 mixer units

We describe the performance of the Band 3 and Band 4 Flight Model mixer units for Herschel/HIFI Instrument. These units are part of the Focal Plane Unit of HIFI. The band 3 and 4 mixer units cover the 800-960 GHz and 960-1120 GHz frequency range and have a 4-8 GHz IF frequency band. The sensitivities of the mixers within the HIFI setting are...

Development of the HIFI band 3 and 4 mixer units

We describe the current status of the HIFI mixer units for Band 3 and Band 4. The mixer units cover the 800-960 GHz and 960-1120 GHz frequency range and have a 4-8 GHz IF frequency band. The major requirements and the design strategy are described. Functional tests of the magnet, the de-flux heater, IF-circuit, and the corrugated horn were...