Institute for Experimental Molecular Imaging, RWTH Aachen University, Aachen, North Rhine-Westphalia, 52074, Germany
Fabian Kiessling – fkiessling@ukaachen.de
Institute for Experimental Molecular Imaging, RWTH Aachen University
Aachen, 52074
Germany
Popular version of 1aBAb3 – Monitoring of neoadjuvant chemotherapy response of breast cancer with ultrasound localization microscopy
Presented at the 186th ASA Meeting
Read the abstract at https://doi.org/10.1121/10.0026657
–The research described in this Acoustics Lay Language Paper may not have yet been peer reviewed–
One in every eight women develops breast cancer over her lifetime. Despite tremendous advances in therapy over the last decades, particularly aggressive breast cancer remains challenging to treat. The current clinical standard is to subject these patients to chemotherapy already before surgically removing their tumor. The ultimate goal of this treatment is to make the tumor disappear completely and to use the surgery solely to confirm that no cancer cells are remaining in the tissue. However, the majority of patients does not sufficiently respond to the chemotherapy treatment. In this case, the therapeutic outcome must be critically weighed against the expected side effects and risks. Therefore, it is highly important to 1) better identify patients that are likely to not sufficiently respond to the therapy (patient preselection) and to 2) make sure that patients subjected to therapy do indeed respond (therapy monitoring).
Figure 1: Super-resolution ultrasound image of a human breast tumor.
In our study, we are investigating the use of super-resolution ultrasound (Fig. 1) for these two applications. This emerging technique provides histology-like images of vessel trees and allows to determine the blood flow within each individual vessel, thus providing new information on microvascular perfusion. As the vascular system is tightly bound to tumor development, we hypothesize that super-resolution ultrasound might reveal differences between fully and incompletely responding patients.
To investigate this, we examined breast cancer patients during their chemotherapy treatment. More precisely, we characterized their tumor right before they received their first, second, and fourth dose of chemotherapeutics. Here, we measured the tumor size and recorded ultrasound videos in which we highlighted the vessels using a contrast agent. We subsequently post-processed these videos to obtain super-resolution images of the vessel architecture and blood flow velocities. Finally, we extracted a multitude of morphological and functional vessel features, which together form a vascular fingerprint.
Our approach revealed that patients responding fully to therapy differed noticeably from partial responders before the start of chemotherapy. Their tumors were more vascularized, their vessels more tortuous, and the vessel architecture was different. Both patient groups could be distinguished with high accuracy when applying a first classification approach. During chemotherapy, many features associated with malignancy normalized in case of full responders, meaning that the vessels resembled more and more those of healthy tissue. In contrast, this was not observed for partial responders.
These findings show that super-resolution ultrasound might be able to fill a tremendous gap in therapy monitoring and, especially, patient preselection of breast cancer patients. Being able to identify patients that insufficiently respond to therapy would avoid the side effects of an ineffective therapy and would allow the medical doctors to look for a more adequate treatment. In that way, super-resolution ultrasound could considerably improve the therapy outcome of these patients.
Michael Oelze – oelze@illinois.edu
X (Twitter): @Oelze_Url
University of Illinois at Urbana-Champaign
Urbana, IL 61801
United States
Zhengchang Kou
University of Illinois at Urbana-Champaign
Urbana, IL 61801
United States
Popular version of 1pBAb7 – Contrast-Free Microvessel Imaging Using Null Subtraction Imaging Combined with Harmonic Imaging
Presented at the 186th ASA Meeting
Read the abstract at https://doi.org/10.1121/10.0026780
–The research described in this Acoustics Lay Language Paper may not have yet been peer reviewed–
Bubbles? We don’t need no stinking bubbles!
In recent years, super resolution imaging techniques for imaging the microvasculature have been developed and demonstrated for applications such as functional ultrasound imaging in mice and assessing Alzheimer’s disease in pre-clinical models. While these novel super resolution techniques have produced images with incredible detail and vessel contrast, one drawback to the approach is the need to inject contrast agents, which consist of small gas-filled microbubbles. This reduces the clinical application and adoption of these techniques. Furthermore, the time required to construct these images can take hours because it involves localizing and tracking individual microbubbles as they progress through the vasculature.
FIGURE 1: Video of 3D rendering of rat brain using traditional approaches at a fundamental frequency (top left) and at twice the fundamental frequency (bottom left) compared to using our novel approach (NSI) at a fundamental frequency (top right) and at twice the fundamental frequency (bottom right) (please note this will be a playable video online)
In our novel approach to microvessel imaging, we don’t need no stinking microbubbles! Instead, we utilize a novel nonlinear beamforming approach that allows fast reconstructions with much better spatial resolution. This allows us to approach super resolution without the need to inject microbubbles into the body. Along with the beamforming approach we also use a pulse inversion scheme, where we transmit with one frequency and receive with twice the transmit frequency. This allows a doubling of the spatial resolution over receiving with the same transmit frequency. However, the use of pulse inversion scheme can introduce unwanted clutter into the image. With our novel beamforming approach, clutter is greatly reduced or eliminated from the images.
FIGURE 2 Single image frames comparing traditional power Doppler methods (left) with our novel approach (right).
We demonstrated our new technology in a rat brain (both 2D and a 3D rendering) and rabbit kidney and compared our images to traditional beamforming approaches without the use of contrast agents. The video shows a 3D rendering of the microvasculature of a rat brain and the corresponding figure shows a particular frame of the 3D rendering. We showed that our approach eliminates the clutter produced by the pulse inversion scheme, increases the contrast of microvessel images, results in more observable vessels, and produces a much finer spatial resolution better than one fourth of a wavelength. The time to reconstruct the images using our novel technique was a fraction of the time needed for current super resolution techniques that rely on localizing and tracking microbubbles in the vasculature. Therefore, our novel approach could provide microbubble-free technology to produce high-resolution power Doppler images of the microvasculature with the potential for clinical applications.
Jian-yu Lu – jian-yu.lu@ieee.org
X (Twitter): @Jianyu_lu
Instagram: @jianyu.lu01
Department of Bioengineering, College of Engineering, The University of Toledo, Toledo, Ohio, 43606, United States
Popular version of 1pBAb4 – Reconstruction methods for super-resolution imaging with PSF modulation
Presented at the 186 ASA Meeting
Read the abstract at https://doi.org/10.1121/10.0026777
–The research described in this Acoustics Lay Language Paper may not have yet been peer reviewed–
Imaging is an important fundamental tool to advance science, engineering, and medicine, and is indispensable in our daily life. Here we have a few examples: Acoustical and optical microscopes have helped to advance biology. Ultrasound imaging, X-ray radiography, X-ray computerized tomography (X-ray CT), magnetic resonance imaging (MRI), gamma camera, single-photon emission computerized tomography (SPECT), and positron emission tomography (PET) have been routinely used for medical diagnoses. Electron and scanning tunneling microscopes have revealed structures in nanometer or atomic scale, where one nanometer is one billionth of a meter. And photography, including the cameras in cell phones, is in our everyday life.
Despite the importance of imaging, it was first recognized by Ernest Abbe in 1873 that there is a fundamental limit known as the diffraction limit for resolution in wave-based imaging systems due to the diffraction of waves. This effects acoustical, optical, and electromagnetic waves, and so on.
Recently (see Lu, IEEE TUFFC, January 2024), the researcher developed a general method to overcome such a long-standing diffraction limit. This method is not only applicable to wave-based imaging systems such as ultrasound, optical, electromagnetic, radar, and sonar; it is in principle also applicable to other linear shift-invariant (LSI) imaging systems such as X-ray radiography, X-ray CT, MRI, gamma camera, SPECT, and PET since it increases image resolution by introducing high spatial frequencies through modulating the point-spread function (PSF) of an LSI imaging system. The modulation can be induced remotely from outside of an object to be imaged, or can be small particles introduced into or on the surface of the object and manipulated remotely. The LSI system can be understood with a geometric distortion corrected optical camera in the photography, where the photo of a person will be the same or invariant in terms of the size and shape if the person only shifts his/her position in the direction that is perpendicular to the camera optical axis within the camera field of view.
Figure 1 below demonstrates the efficacy of the method using an acoustical wave. The method was used to image a passive object (in the first row) through a pulse-echo imaging or to image wave source distributions (in the second row) with a receiver. The best images obtainable under the Abbe’s diffraction limit are in the second column, and the super-resolution (better than the diffraction limit) images obtained with the new method are in the last column. The super-resolution images had a resolution that was close to 1/3 of the wavelength used from a distance with an f-number (focal distance divided by the diameter of the transducer) close to 2.
Because the method developed is based on the convolution theory of an LSI system and many practical imaging systems are LSI, the method opens an avenue for various new applications in science, engineering, and medicine. With a proper choice of a modulator and imaging system, nanoscale imaging with resolution similar to that of a scanning electron microscope (SEM) is possible even with visible or infrared light.
Wearable Ultrasound Monitor Can Aid Rehabilitation from Injury #Acoustics23
A new approach to ultrasound imaging can provide real-time insights into muscle dynamics.
SYDNEY, Dec. 5, 2023 – Millions suffer from musculoskeletal injuries every year, and the recovery process can often be long and difficult. Patients typically undergo rehabilitation, slowly rebuilding muscle strength as their injuries heal. Medical professionals routinely evaluate a patient’s progress via a series of tasks and exercises. However, because of the dynamic nature of these exercises, obtaining a clear picture of real-time muscle function is extremely challenging.
Parag Chitnis of George Mason University led a team that developed a wearable ultrasound system that can produce clinically relevant information about muscle function during dynamic physical activity. He will present his work Dec. 5 at 5:00 p.m. Australian Eastern Daylight Time, as part of Acoustics 2023 running Dec. 4-8 at the International Convention Centre Sydney
A wearable ultrasound monitor can provide insight into dynamic muscle movement during activities like jumping. Credit: Parag Chitnis
Many medical technologies can give doctors a window into the inner workings of a patient’s body, but few can be used while that patient is moving. A wearable ultrasound monitor can move with the patient and provide an unprecedented level of insight into body dynamics.
“For instance, when an individual is performing a specific exercise for rehabilitation, our devices can be used to ensure that the target muscle is actually being activated and used correctly,” said Chitnis. “Other applications include providing athletes with insights into their physical fitness and performance, assessing and guiding recovery of motor function in stroke patients, and assessing balance and stability in elderly populations during routine everyday tasks.”
Designing a wearable ultrasound device took much more than simply strapping an existing ultrasound monitor to a patient. Chitnis and his team reinvented ultrasound technology nearly from scratch to produce the results they needed.
“We had to completely change the paradigm of ultrasound imaging,” said Chitnis. “Traditionally, ultrasound systems transmit short-duration pulses, and the echo signals are used to make clinically usefully images. Our systems use a patented approach that relies on transmission of long-duration chirps, which allows us to perform ultrasound sensing using the same components one might find in their car radio.”
This modified approach allowed the team to design a simpler, cheaper system that could be miniaturized and powered by batteries. This let them design an ultrasound monitor with a small, portable form factor that could be attached to a patient.
Soon, Chitnis hopes to further improve his device and develop software tools to more quickly interpret and analyze the ultrasound signals.
The Acoustical Society of America is joining the Australian Acoustical Society to co-host Acoustics 2023 Sydney. This collaborative event will incorporate the Western Pacific Acoustics Conference and the Pacific Rim Underwater Acoustics Conference.
ASA PRESS ROOM In the coming weeks, ASA’s Press Room will be updated with newsworthy stories and the press conference schedule at https://acoustics.org/asa-press-room/.
LAY LANGUAGE PAPERS ASA will also share dozens of lay language papers about topics covered at the conference. Lay language papers are summaries (300-500 words) of presentations written by scientists for a general audience. They will be accompanied by photos, audio, and video. Learn more at https://acoustics.org/lay-language-papers/.
PRESS REGISTRATION ASA will grant free registration to credentialed and professional freelance journalists. If you are a reporter and would like to attend the meeting or virtual press conferences, contact AIP Media Services at media@aip.org. For urgent requests, AIP staff can also help with setting up interviews and obtaining images, sound clips, or background information.
ABOUT THE ACOUSTICAL SOCIETY OF AMERICA The Acoustical Society of America (ASA) is the premier international scientific society in acoustics devoted to the science and technology of sound. Its 7,000 members worldwide represent a broad spectrum of the study of acoustics. ASA publications include The Journal of the Acoustical Society of America (the world’s leading journal on acoustics), JASA Express Letters, Proceedings of Meetings on Acoustics, Acoustics Today magazine, books, and standards on acoustics. The society also holds two major scientific meetings each year. See https://acousticalsociety.org/.
ABOUT THE AUSTRALIAN ACOUSTICAL SOCIETY The Australian Acoustical Society (AAS) is the peak technical society for individuals working in acoustics in Australia. The AAS aims to promote and advance the science and practice of acoustics in all its branches to the wider community and provide support to acousticians. Its diverse membership is made up from academia, consultancies, industry, equipment manufacturers and retailers, and all levels of Government. The Society supports research and provides regular forums for those who practice or study acoustics across a wide range of fields The principal activities of the Society are technical meetings held by each State Division, annual conferences which are held by the State Divisions and the ASNZ in rotation, and publication of the journal Acoustics Australia. https://www.acoustics.org.au/
A Farsighted Approach to Tackle Nearsightedness #Acoustics23
Acoustical imaging helps reveal causes and potential cures of myopia.
SYDNEY, Dec. 5, 2023 – Modern living may be contributing to an epidemic of nearsighted vision and related blindness. By 2050, it is estimated that half the world’s population will suffer from low vision due to myopia, a condition where the eye grows too large and can no longer focus on objects in the distance. Human eyes, honed by evolution to survive in the wild, are ill-adapted to city living, contributing to increased cases of myopia, among other factors.
For decades, researcher Sally McFadden from the University of Newcastle has investigated eyes and eyesight in humans and animals. She will present her work and the importance of acoustical imaging Dec. 5 at 10:40 a.m. Australian Eastern Daylight Time, as part of Acoustics 2023 Sydney, running Dec. 4-8 at the International Convention Centre Sydney.
Near-sightedness is on the rise, likely due to modern lifestyles that require seeing objects up close, rather than adjusting to vision in the distance. Credit: American Institute of Physics
As humans age, our eyes adjust based on how we use them, growing or shortening to focus where needed. We now know that blurred input to the eye while the eye is growing causes myopia. It is so specific that the eye grows exactly to compensate for the amount and the direction of blur. For example, if you put the focus behind the retina, the eye grows longer, while if you put the focus in front of the retina, the eye slows its growth and becomes shorter. If the eye grows too long, it becomes myopic or nearsighted. In extreme cases, high myopia is associated with glaucoma, and can increase the risk of retinal detachment and abnormal pathologies around the optic nerve which lead to profound blindness.
“Babies are generally born longsighted, and the changes in the optics of the eye have to coordinate with the eye growth to get to the perfect length for focused vision,” said McFadden. “The problem is that the human eye evolved to suit a hunter-gatherer lifestyle and is not adapted for modern living.”
McFadden and her team built a high-frequency ultrasonography system to measure eye size and how quickly eyes grow to better understand myopia and its contributing factors.
“Education level (amount of study) and the type of light stimulation to the eye all correlate with the amount of myopia you develop,” McFadden said. “Time spent outdoors is protective. Myopia is greater in cities than in rural populations, and even correlates with those that live in small homes.”
Currently, vision-correcting gear like glasses and contacts are the only solution for myopia. However, eyedrops for children with myopia are in development and could halt the vision from worsening. Teams from around the world are collaborating to develop treatments for high myopia to preserve our vision.
The Acoustical Society of America is joining the Australian Acoustical Society to co-host Acoustics 2023 Sydney. This collaborative event will incorporate the Western Pacific Acoustics Conference and the Pacific Rim Underwater Acoustics Conference.
ASA PRESS ROOM In the coming weeks, ASA’s Press Room will be updated with newsworthy stories and the press conference schedule at https://acoustics.org/asa-press-room/.
LAY LANGUAGE PAPERS ASA will also share dozens of lay language papers about topics covered at the conference. Lay language papers are summaries (300-500 words) of presentations written by scientists for a general audience. They will be accompanied by photos, audio, and video. Learn more at https://acoustics.org/lay-language-papers/.
PRESS REGISTRATION ASA will grant free registration to credentialed and professional freelance journalists. If you are a reporter and would like to attend the meeting or virtual press conferences, contact AIP Media Services at media@aip.org. For urgent requests, AIP staff can also help with setting up interviews and obtaining images, sound clips, or background information.
ABOUT THE ACOUSTICAL SOCIETY OF AMERICA The Acoustical Society of America (ASA) is the premier international scientific society in acoustics devoted to the science and technology of sound. Its 7,000 members worldwide represent a broad spectrum of the study of acoustics. ASA publications include The Journal of the Acoustical Society of America (the world’s leading journal on acoustics), JASA Express Letters, Proceedings of Meetings on Acoustics, Acoustics Today magazine, books, and standards on acoustics. The society also holds two major scientific meetings each year. See https://acousticalsociety.org/.
ABOUT THE AUSTRALIAN ACOUSTICAL SOCIETY The Australian Acoustical Society (AAS) is the peak technical society for individuals working in acoustics in Australia. The AAS aims to promote and advance the science and practice of acoustics in all its branches to the wider community and provide support to acousticians. Its diverse membership is made up from academia, consultancies, industry, equipment manufacturers and retailers, and all levels of Government. The Society supports research and provides regular forums for those who practice or study acoustics across a wide range of fields The principal activities of the Society are technical meetings held by each State Division, annual conferences which are held by the State Divisions and the ASNZ in rotation, and publication of the journal Acoustics Australia. https://www.acoustics.org.au/
Technique employs bubbles formed and popped in response to sound waves to deliver vaccines and achieve potentially improved immune response.
SYDNEY, Dec. 4, 2023 – An estimated quarter of adults and two-thirds of children have strong fears around needles, according to the U.S. Centers for Disease Control and Prevention. Yet, public health depends on people being willing to receive vaccines, which are often administered by a jab.
Darcy Dunn-Lawless, a doctoral student at the University of Oxford’s Institute of Biomedical Engineering, is investigating the potential of a painless, needle-free vaccine delivery by ultrasound. He will share the recent advancements in this promising technique as part of Acoustics 2023 Sydney, running Dec. 4-8 at the International Convention Centre Sydney. His presentation will take place Dec. 4 at 11:00 a.m. Australian Eastern Daylight Time.
“Our method relies on an acoustic effect called ‘cavitation,’ which is the formation and popping of bubbles in response to a sound wave,” said Dunn-Lawless. “We aim to harness the concentrated bursts of mechanical energy produced by these bubble collapses in three main ways. First, to clear passages through the outer layer of dead skin cells and allow vaccine molecules to pass through. Second, to act as a pump that drives the drug molecules into these passages. Lastly, to open up the membranes surrounding the cells themselves, since some types of vaccine must get inside a cell to function.”
Though initial in vivo tests reported 700 times fewer vaccine molecules were delivered by the cavitation approach compared to conventional injection, the cavitation approach produced a higher immune response. The researchers theorize this could be due to the immune-rich skin the ultrasonic delivery targets in contrast to the muscles that receive the jab. The result is a more efficient vaccine that could help reduce costs and increase efficacy with little risk of side effects.
“In my opinion, the main potential side effect is universal to all physical techniques in medicine: If you apply too much energy to the body, you can damage tissue,” Dunn-Lawless said. “Exposure to excessive cavitation can cause mechanical damage to cells and structures. However, there is good evidence that such damage can be avoided by limiting exposure, so a key part of my research is to try and fully identify where this safety threshold lies for vaccine delivery.”
Ultrasound pulses deliver vaccines through the skin without needles. This technique, which employs sound waves to create bubbles that forge a path for the vaccine, may be especially helpful for DNA vaccines. Credit: Darcy Dunn-Lawless
Dunn-Lawless works as part of a larger team under the supervision of Dr. Mike Gray, Professor Bob Carlisle, and Professor Constantin Coussios within Oxford’s Biomedical Ultrasonics, Biotherapy and Biopharmaceuticals Laboratory (BUBBL). Their cavitation approach may be particularly conducing to DNA vaccines that are currently difficult to deliver. With cavitation able to help crack open the membranes blocking therapeutic access to the cell nucleus, the other advantages of DNA vaccines, like a focused immune response, low infection risk, and shelf stability, can be better utilized.
The Acoustical Society of America is joining the Australian Acoustical Society to co-host Acoustics 2023 Sydney. This collaborative event will incorporate the Western Pacific Acoustics Conference and the Pacific Rim Underwater Acoustics Conference.
ASA PRESS ROOM In the coming weeks, ASA’s Press Room will be updated with newsworthy stories and the press conference schedule at https://acoustics.org/asa-press-room/.
LAY LANGUAGE PAPERS ASA will also share dozens of lay language papers about topics covered at the conference. Lay language papers are summaries (300-500 words) of presentations written by scientists for a general audience. They will be accompanied by photos, audio, and video. Learn more at https://acoustics.org/lay-language-papers/.
PRESS REGISTRATION ASA will grant free registration to credentialed and professional freelance journalists. If you are a reporter and would like to attend the meeting or virtual press conferences, contact AIP Media Services at media@aip.org. For urgent requests, AIP staff can also help with setting up interviews and obtaining images, sound clips, or background information.
ABOUT THE ACOUSTICAL SOCIETY OF AMERICA The Acoustical Society of America (ASA) is the premier international scientific society in acoustics devoted to the science and technology of sound. Its 7,000 members worldwide represent a broad spectrum of the study of acoustics. ASA publications include The Journal of the Acoustical Society of America (the world’s leading journal on acoustics), JASA Express Letters, Proceedings of Meetings on Acoustics, Acoustics Today magazine, books, and standards on acoustics. The society also holds two major scientific meetings each year. See https://acousticalsociety.org/.
ABOUT THE AUSTRALIAN ACOUSTICAL SOCIETY The Australian Acoustical Society (AAS) is the peak technical society for individuals working in acoustics in Australia. The AAS aims to promote and advance the science and practice of acoustics in all its branches to the wider community and provide support to acousticians. Its diverse membership is made up from academia, consultancies, industry, equipment manufacturers and retailers, and all levels of Government. The Society supports research and provides regular forums for those who practice or study acoustics across a wide range of fields The principal activities of the Society are technical meetings held by each State Division, annual conferences which are held by the State Divisions and the ASNZ in rotation, and publication of the journal Acoustics Australia. https://www.acoustics.org.au/
FIGURE 2 Single image frames comparing traditional power Doppler methods (left) with our novel approach (right).
