Software Update: Now Available for Vantage® System Customers
Verasonics has announced to customers its latest Vantage software release (ver. 4.9.6). This software release is now available for download via customer folders, providing access to updated features and options.
Essentials of Ultrasound Imaging Course
The Essentials of Ultrasound Imaging Course, a new educational offering from Verasonics, provides a new way of teaching and learning about ultrasound imaging. The Essentials of Ultrasound Imaging Course, a unique curriculum, was developed by Professor Thomas Szabo of Boston University and Dr. Peter Kaczkowski of Verasonics. The curriculum combines directed teaching from the textbook “Essentials of Ultrasound Imaging,”1 which is also written by Professor Szabo and Dr. Kaczkowski, and was published by Elsevier in December 2023, along with lectures, interactive exploration through GUI-based simulators, and hands-on laboratory experiments using a Vantage Research Ultrasound System. This curriculum is designed to be taught by an experienced instructor at an academic institution or commercial organization.
The curriculum follows the material laid out in the textbook chapter-by-chapter, with ten lectures of approximately one hour provided as detailed slide presentations and notes. This course is ideal for new graduate students and/or engineers in industry; however, the material will appeal to a wider circle of students and instructors. A secondary audience is those who are involved in, or starting, ultrasound research and development, but may not have a technical background to fully comprehend the latest developments in this arena. This secondary audience might also include scientists and engineers from other disciplines, physicians, sonographers, managers of research or engineering groups, as well as those curious about ultrasound science. Though the content is mainly based on medical ultrasound, the basic principles presented can be applied to other purposes such as non-destructive evaluation and geophysics.
An example of how this introductory curriculum might work is in teaching the concept of grating lobes – imaging artifacts caused by under sampling or when the spacing of array elements, explained in chapters 6 and 7 of the textbook which are focused on pulsed arrays, is when the element period to wavelength ratio is equal to or less than 0.5. Traditional teaching of a concept such as grating lobes in a lecture environment and study of a textbook only goes so far to explain the concepts. Instead, the second part of the curriculum provides an alternative way of teaching: interactive software simulators which engage students with the material at a deeper level. Below, the graphical user interface (GUI) of the Pulsed Array Simulator is shown in Fig.1 with annotated controls. Fig. 2 then shows a surface field plot generated by this software simulator for an under sampled array and demonstrates noticeable grating lobes.
1https://shop.elsevier.com/books/essentials-of-ultrasound-imaging/szabo/978-0-323-95371-9
Pulsed Array Program
Figure 2: Pulsed Array Simulator generated surface field plot for Focus at 40 wavelengths, N=20 elements, aperture L=40 wavelengths F#=1, and period p=2.0 wavelengths.
This simulator, one of 27 developed as part of the curriculum, provides thousands of combinations from which to understand the meaning and impact of array design. In effect, these simulators bring to life a complicated sequence of computational steps and algorithms by replacing input variables by controls such as sliders and knobs, output variables by selected output displays and the presentation of output by display options. Furthermore, these simulators do not require any knowledge of simulation programming to run and therefore can provide an understanding of the concepts without any advanced mathematics and physics background.
In combination with the other curriculum elements, these simulators have been designed to offer an in-depth grounding of the theories presented. The simulators are provided as a downloadable executable that can be run in near real-time on a standard laptop on either Windows or macOS platforms. Verasonics is pleased to make these simulators available as a free download via our website. Visit Essentials of Ultrasound Imaging Simulators for more information.
Another simulator, Scatter Image2, is used to generate the resultant ultrasound image (shown in Fig. 3) illustrating what grating lobe distortion appears as for the same case of period p=2.0 wavelengths.
2The two simulators shown here use rapid calculations performed by FOCUS developed by Prof Robert J. McGough’s group at Michigan State University (https://www.egr.msu.edu/~fultras-web/)
Figure 3: Scatter Imaging simulator for a 2.5 MHz array focused at 3 cm on transmit and receive and with a period p=2.0 wavelengths.
The third part of the curriculum consists of live demonstrations of the concepts by using the Vantage System. This portion of the curriculum consists of lab lecture slides for an instructor to deliver, an instructor manual explaining the expected results in each lab session, and supplementary laboratory imaging kits for the students to conduct the experiment. The use of the Vantage System provides unparalleled insight into each step of ultrasound image creation including signal processing, transducer operation, different types of beamforming, and image formation. There are nine laboratory sessions designed to be combined with textbook and software simulators. Each laboratory session has designed Vantage sequence scripts and appropriate progressively advanced GUIs specifically written for each lab module to facilitate turn-key operation, experimentation and data collection on Vantage Systems. In addition, most labs utilize a custom experimental test phantom designed to illustrate a hands-on experience of the concepts and produce quantitative results. An example of images for a laboratory session on grating lobes is given in Fig. 4. In this experiment, a custom lab script changes the operation of the Vantage System to allow the selection of the operating frequency and change the element period to wavelength ratios of an L11-5v linear array transducer.
Fig.4 Grating lobes observed by varying the frequency for the L11-5v transducer, from the imaging of scattering and artifacts related to pin targets in water. Dynamic receive focusing was used in these images. Effective element period to wavelength ratios for these cases are 1.0, 1.5 and 2.2 wavelengths.
In summary, the curriculum for the Verasonics Essentials of Ultrasound Imaging Course offers a unique, comprehensive multi-experiential fast-track introduction to the science, physics, and technology of ultrasound imaging, as well as to the use of a Verasonics Vantage System. Learn more here.
For questions on the Essentials of Ultrasound Imaging Course, Vantage Research Ultrasound Systems or other Verasonics solutions, contact [email protected].