Acoustic diffraction-resistant adaptive profile technology for elasticity imaging – Life Changer

Acoustic diffraction-resistant adaptive profile technology for elasticity imaging

[ad_1]

This article has been reviewed according to Science X’s editorial process
and policies.
Editors have highlighted the following attributes while ensuring the content’s credibility:

fact-checked

peer-reviewed publication

trusted source

proofread


Beam-shaping mechanism of the acoustic diffraction–resistant adaptive profile technology (ADAPT). (A) Illustration of the propagation-invariant acoustic beam generated using ADAPT. An arbitrary axial acoustic beam profile can be defined and realized via weighted Bessel beam superposition. (B) A schematic of the beam-shaping procedures. An arbitrary axial acoustic profile can be expanded as a superposition of various aligned Bessel beams with corresponding weights. The ADAPT-based beam can be generated by beam multiplexing. (C) The orthoslice of the acoustic field of three generated ADAPT-based beams with different profiles. The ADAPT-based beams can be compressed, stretched, and divided into different shapes. a.u., arbitrary units. Credit: Science Advances, doi; 10.1126/sciadv.adi6129

× close


Beam-shaping mechanism of the acoustic diffraction–resistant adaptive profile technology (ADAPT). (A) Illustration of the propagation-invariant acoustic beam generated using ADAPT. An arbitrary axial acoustic beam profile can be defined and realized via weighted Bessel beam superposition. (B) A schematic of the beam-shaping procedures. An arbitrary axial acoustic profile can be expanded as a superposition of various aligned Bessel beams with corresponding weights. The ADAPT-based beam can be generated by beam multiplexing. (C) The orthoslice of the acoustic field of three generated ADAPT-based beams with different profiles. The ADAPT-based beams can be compressed, stretched, and divided into different shapes. a.u., arbitrary units. Credit: Science Advances, doi; 10.1126/sciadv.adi6129

Acoustic beam shaping with high degrees of freedom is critical for ultrasound imaging, acoustic regulation, and stimulation. The ability to fully regulate the acoustic pressure profile relative to its propagation path remains to be achieved.

In a new report published in Science Advances, Yuyang Gu, and a team of scientists in radiology at the Massachusetts General Hospital, U.S., describe an acoustic diffraction-resistant adaptive profile technology to generate a propagation invariant beam with a desired profile.

To accomplish this, they leveraged the wave number and beam multiplexing to develop a general framework and create a highly flexible beam with a linear array ultrasound transducer. The designed acoustic beam maintained a beam profile in the material by compensating attenuation.

The scientists showed shear wave elasticity imaging as an important modality to benefit from the method to evaluate tissue mechanical properties. Together, the technology overcame existing limits of acoustic beam shaping suited for a variety of applications including medicine, biology, and materials science.

Acoustic beams

The interest in shaping a desired acoustic beam has broad applications across biomedical imaging, sensing, and particle manipulation. Such acoustic beam methods are inspired by the fundamental physics governing wave propagation to benefit multidisciplinary fields including biology, and biomedical engineering.

Researchers have hitherto considered a class of acoustic beams known as propagation-invariant or nondiffracting beams. The classic propagation-invariant beams include the Bessel beam, airy beam, Mathieu, and Weber beam; each with unique features for wide-ranging applications in optical research.

Examples include optical tweezers, ultra-resolution imaging, and nanoscale material processing. The acoustic beam Bessel is suited for telecommunication, and acoustic tweezers, where the acoustic airy beam can efficiently bypass any obstacle in the wave propagation path.

Generating the acoustic diffraction–resistant adaptive profile technology (ADAPT)

In this work, Gu and colleagues described a generalized framework to generate propagation-invariant acoustic beams known as acoustic diffraction-resistant adaptive profile technology (ADAPT) to realize arbitrary longitudinal pressure distributions. The scientists first introduced the basic concept with superimposed Bessel beams to realize beam shaping with a linear array transducer.

While the conventional focused beam only provided a limited effective imaging area at the beam focal depth, the method produced a beam with a user-defined region of interest to obtain an extended imaging area with higher accuracy.


Generation of an acoustic diffraction–resistant adaptive profile technology (ADAPT)-based beam with a single multielement acoustic transducer via beam multiplexing. (A) A schematic of a linear-array transducer consists of multiple elements with controllable pressure and phase. (B) The superposed pressure/apodization function assigned to the acoustic transducer. (C) The superposed phase and corresponding delay function assigned to the acoustic transducer. (D) The acoustic field of one example ADAPT-based beam with a localized pressure distribution along the axial center line. (E) The simulated acoustic pressure distribution along the horizontal middle line. (F) The simulated acoustic pressure distribution along the axial center line. (G) The ADAPT is able to induce the shear wave in an elastic medium through acoustic radiation force. With various beam lengths of ADAPT-based beams, shear waves with different wave profiles are produced. a.u., arbitrary units. Credit: Science Advances, doi; 10.1126/sciadv.adi6129

× close


Generation of an acoustic diffraction–resistant adaptive profile technology (ADAPT)-based beam with a single multielement acoustic transducer via beam multiplexing. (A) A schematic of a linear-array transducer consists of multiple elements with controllable pressure and phase. (B) The superposed pressure/apodization function assigned to the acoustic transducer. (C) The superposed phase and corresponding delay function assigned to the acoustic transducer. (D) The acoustic field of one example ADAPT-based beam with a localized pressure distribution along the axial center line. (E) The simulated acoustic pressure distribution along the horizontal middle line. (F) The simulated acoustic pressure distribution along the axial center line. (G) The ADAPT is able to induce the shear wave in an elastic medium through acoustic radiation force. With various beam lengths of ADAPT-based beams, shear waves with different wave profiles are produced. a.u., arbitrary units. Credit: Science Advances, doi; 10.1126/sciadv.adi6129

Shaping propagation-invariant acoustic beams

There are two well-established methods to shape an acoustic beam. One method aims to classically shape focused beams by combining a predefined single focal position and the information of the acoustic source. The other method aims to directly map the known pressure or phase distribution function including the Bessel function to each pixel in the acoustic source. Both methods are suited to regulate the longitudinal acoustic profile of the beam.

The ADAPT method (acoustic diffraction-resistant adaptive profile technology) introduced in this work combined both methods by separating a predefined acoustic beam into multiple Bessel beams with different wave numbers and coefficients. The schematic of the ADAPT-based beam with an example predefined pressure profile includes a random, three-section high-pressure region defined as an ‘isolated’ and propagation-invariant pattern.

A set of Bessel beams formed the final beam, therefore the non-diffractive beam markedly decreased pressure outside the desired high-pressure region via wave-interference. By separating the beam into multiple weighted Bessel beams, Gu and team interpolated the amplitude and phase distribution of each pixel or element to coherently sum up the final amplitude and phase applied to the acoustic transducer.

The team showed how the ADAPT-based beam profiles can be stretched flexibly, compressed, or divided, to generate acoustic beams at different axial locations.


Attenuation-compensated acoustic diffraction–resistant adaptive profile technology (ADAPT)-based beams. (A) A schematic of an ADAPT-based beam without attenuation. (B) A schematic showing a complex wave number can be assigned during the ADAPT calculation that incorporates the attenuation coefficient to compensate for attenuation. (C) The simulated acoustic pressure in the absence of attenuation and compensation. It indicates the originally designed beam profile at the desired location. (D) The simulated acoustic pressure when attenuation is included without compensation. The beam profile and location are distorted. (E) The simulated acoustic pressure when medium attenuation and compensation are included. The beam distortion from attenuation is minimized. (F to H) Plots of the axial center-line pressure distribution correspond to three scenarios in (C) to (E), respectively. (I) The simulated acoustic intensity of the originally designed ADAPT-based beam. (J) The experimental generated shear wave without compensation. The acoustic transducer is located at z = 0 with the center aligned with the shear wave field center. (K) The experimental generated shear wave when attenuation is compensated. The shear wave profile matches the designed ADAPT-based beam profile. a.u., arbitrary units. Credit: Science Advances, doi; 10.1126/sciadv.adi6129

× close


Attenuation-compensated acoustic diffraction–resistant adaptive profile technology (ADAPT)-based beams. (A) A schematic of an ADAPT-based beam without attenuation. (B) A schematic showing a complex wave number can be assigned during the ADAPT calculation that incorporates the attenuation coefficient to compensate for attenuation. (C) The simulated acoustic pressure in the absence of attenuation and compensation. It indicates the originally designed beam profile at the desired location. (D) The simulated acoustic pressure when attenuation is included without compensation. The beam profile and location are distorted. (E) The simulated acoustic pressure when medium attenuation and compensation are included. The beam distortion from attenuation is minimized. (F to H) Plots of the axial center-line pressure distribution correspond to three scenarios in (C) to (E), respectively. (I) The simulated acoustic intensity of the originally designed ADAPT-based beam. (J) The experimental generated shear wave without compensation. The acoustic transducer is located at z = 0 with the center aligned with the shear wave field center. (K) The experimental generated shear wave when attenuation is compensated. The shear wave profile matches the designed ADAPT-based beam profile. a.u., arbitrary units. Credit: Science Advances, doi; 10.1126/sciadv.adi6129

Beam multiplexing

The team found that simultaneously generating the requisite Bessel beams by using a single multielement acoustic wave was challenging. Unlike propagation-invariant laser beams that are generated by using a combination of multiple lenses and photomasks, the acoustic propagation invariant wave maintained a narrower spatial frequency bandwidth that corresponded to limited spatial modulation capabilities. As a result, Gu and team used a multiplexing method to generate the ADAPT-based beam with the desired features.

In its mechanism-of-action, the scientists aligned the beam with the highest transverse spatial frequency requirement to the array element size by using the total spectral bandwidth of the transducer to simultaneously produce multiple acoustic beams with different wave numbers.

The variables of frequency, pitch and element size affected the transverse and axial wave numbers to influence the spatial bandwidth of the acoustic beam. While higher frequencies yielded narrower beams with increased resolution and limited penetration depth, lower frequencies resulted in wider beams with increased penetration but lower resolution. Gu and colleagues adjusted the pitch and element size to regulate spatial resolution, to enable a wider range of beam generating possibilities.

Adaptive shear wave generation via ADAPT

When an acoustic wave is propagating inside a material, this will generate an acoustic radiation force. Such radiation forces are proportional to the rate of change of momentum of an acoustic wave propagating in a medium.

Gu and team showed how the impulsive excitation of an acoustic beam can induce the transient laterally propagating shear wave with a shape that depends on the geometry of the beam. This shear wave speed is directly proportional to the elastic properties of the medium, allowing the researchers to conduct experiments inside a tissue-mimicking phantom with the Verasonics research scanner. The team regulated the specific input parameters, including beam center location and length to achieve the desired line-shape profile.


Illustration of phase-only acoustic diffraction–resistant adaptive profile technology (ADAPT) on a linear-array transducer and application of shear wave elasticity imaging. (A) Schematic of the phase-only ADAPT-based beam-shaping mechanism. Each element with specific pressure and phase is divided into two subelements with uniform pressure and different phases. (B) Schematic of the element dividing for phase-only ADAPT and corresponding acoustic pressure of each part of the aperture. The entire aperture is divided into two parts with interleaved elements. Each portion of the aperture can form part of the ADAPT-based beam, and then the set is superposed to shape the final beam. (C) The simulated acoustic field through phase-only modulation. Inset: The comparison of apodization and delay before and after the phase modulation. The information of apodization is encoded into the delay function with a sawtooth distribution. (D) Schematic of the experimental configuration applying phase-only ADAPT for shear wave elasticity imaging. An inclusion is embedded in the phantom. The distance between the phantom and transducer is varied to show inclusions at different depths. A water dam is used when the distance between the phantom and the transducer is too short. (E) Inclusion delineation performance is compared between the focused beam and the ADAPT-based beam. For each beam, two different beam depths are configured at 15 and 20 mm. Scale bar, 2 mm. (F) The contrast-to-noise ratio (CNR) and average shear wave speed (SWS) inside the inclusion are calculated and compared between the cases using the focused beam and the ADAPT-based beam. The ADAPT-based beam produces two times better CNR and more accurate shear wave speed estimate than the focused beam. a.u., arbitrary units. Credit: Science Advances, doi; 10.1126/sciadv.adi6129

× close


Illustration of phase-only acoustic diffraction–resistant adaptive profile technology (ADAPT) on a linear-array transducer and application of shear wave elasticity imaging. (A) Schematic of the phase-only ADAPT-based beam-shaping mechanism. Each element with specific pressure and phase is divided into two subelements with uniform pressure and different phases. (B) Schematic of the element dividing for phase-only ADAPT and corresponding acoustic pressure of each part of the aperture. The entire aperture is divided into two parts with interleaved elements. Each portion of the aperture can form part of the ADAPT-based beam, and then the set is superposed to shape the final beam. (C) The simulated acoustic field through phase-only modulation. Inset: The comparison of apodization and delay before and after the phase modulation. The information of apodization is encoded into the delay function with a sawtooth distribution. (D) Schematic of the experimental configuration applying phase-only ADAPT for shear wave elasticity imaging. An inclusion is embedded in the phantom. The distance between the phantom and transducer is varied to show inclusions at different depths. A water dam is used when the distance between the phantom and the transducer is too short. (E) Inclusion delineation performance is compared between the focused beam and the ADAPT-based beam. For each beam, two different beam depths are configured at 15 and 20 mm. Scale bar, 2 mm. (F) The contrast-to-noise ratio (CNR) and average shear wave speed (SWS) inside the inclusion are calculated and compared between the cases using the focused beam and the ADAPT-based beam. The ADAPT-based beam produces two times better CNR and more accurate shear wave speed estimate than the focused beam. a.u., arbitrary units. Credit: Science Advances, doi; 10.1126/sciadv.adi6129

Outlook

In this way, Yuyang Gu and colleagues describe a method known as acoustic diffraction–resistant adaptive profile technology (ADAPT), to generate propagation-invariant acoustic beams. Such beams can be generated with a single, linear-array transducer using Bessel beam multiplexing.

This method offered a high degree of freedom to regulate the longitudinal acoustic energy, and optimize the method across a variety of applications. The non-diffracting nature of the ADAPT-based beams allowed acoustic attenuation and diffraction in the material for the acoustic beam to maintain the desired profile effectively during propagation.

Gu and colleagues suggest the introduction of a variety of add-on features, to increase its applications, including shear wave elasticity suited for medical imaging, sonar, and acoustic tweezers.

More information:
Yuyang Gu et al, Acoustic diffraction–resistant adaptive profile technology (ADAPT) for elasticity imaging, Science Advances (2023). DOI: 10.1126/sciadv.adi6129

Journal information:
Science Advances


[ad_2]

Source link

Loading

59 thoughts on “Acoustic diffraction-resistant adaptive profile technology for elasticity imaging

  1. We absolutely love your blog and find most of your post’s to be
    just what I’m looking for. Would you offer guest writers to write content for yourself?
    I wouldn’t mind publishing a post or elaborating on many of the subjects
    you write concerning here. Again, awesome web site!

  2. Hello this is somewhat of off topic but I was wanting to know if
    blogs use WYSIWYG editors or if you have to manually code with HTML.
    I’m starting a blog soon but have no coding know-how so I wanted to get advice from someone with
    experience. Any help would be enormously appreciated!

  3. Write more, thats all I have to say. Literally, it seems as though you relied on the video to make your
    point. You definitely know what youre talking about, why throw away your intelligence on just posting videos to
    your blog when you could be giving us something informative to read?

  4. What’s up it’s me, I am also visiting this web site regularly,
    this web site is genuinely pleasant and the viewers are genuinely sharing nice thoughts.

  5. A person essentially assist to make significantly articles I
    would state. This is the first time I frequented your website page and
    so far? I surprised with the research you made to make this particular publish
    extraordinary. Excellent process!

  6. I blog frequently and I truly thank you for your content.
    Your article has truly peaked my interest. I am going to book mark your site and keep checking for new details about once a
    week. I opted in for your Feed too.

  7. Hey I know this is off topic but I was wondering if you knew of any widgets I could add
    to my blog that automatically tweet my newest twitter updates.

    I’ve been looking for a plug-in like this for quite some time and was
    hoping maybe you would have some experience with something like this.
    Please let me know if you run into anything. I truly
    enjoy reading your blog and I look forward to your new
    updates.

  8. After exploring a number of the blog articles on your
    blog, I honestly appreciate your technique of blogging.
    I bookmarked it to my bookmark site list and will be
    checking back soon. Please visit my web site as well and
    let me know what you think.

  9. Hi there! I could have sworn I’ve been to
    this website before but after reading through some of the post I realized it’s new to me.
    Anyways, I’m definitely glad I found it and I’ll be bookmarking
    and checking back frequently!

  10. Hey There. I discovered your weblog using msn. This is
    a very well written article. I’ll be sure to bookmark it and return to
    learn extra of your useful information. Thank you for the post.

    I’ll definitely comeback.

  11. Hello would you mind letting me know which web
    host you’re working with? I’ve loaded your blog in 3 completely different web browsers and I must say this blog loads a
    lot quicker then most. Can you recommend a good internet hosting provider at a
    honest price? Kudos, I appreciate it!

  12. I was wondering if you ever considered changing the structure of your website?

    Its very well written; I love what youve got to say.
    But maybe you could a little more in the way
    of content so people could connect with it better.
    Youve got an awful lot of text for only having one or two pictures.

    Maybe you could space it out better?

  13. What i don’t understood is actually how you are no longer really much more neatly-liked than you might be now.
    You are so intelligent. You know thus considerably with regards to this topic, made me individually consider it from a lot of
    various angles. Its like men and women are not interested except it’s one thing
    to do with Lady gaga! Your personal stuffs excellent.
    At all times care for it up!

  14. You actually make it appear so easy along with your
    presentation but I find this topic to be really something which I feel I might by no means
    understand. It sort of feels too complex and very broad for me.
    I am looking ahead in your subsequent put up, I’ll try to get the
    grasp of it!

  15. Whoa! This blog looks just like my old one! It’s on a entirely different
    subject but it has pretty much the same page layout and design. Excellent choice of colors!

  16. Just wish to say your article is as surprising. The clarity in your post
    is just great and i can assume you’re an expert on this subject.

    Fine with your permission let me to grab your RSS feed to
    keep up to date with forthcoming post. Thanks a million and please carry on the gratifying work.

  17. I have read several just right stuff here. Definitely value
    bookmarking for revisiting. I wonder how much effort you put to make any such magnificent informative site.

  18. Greetings! Very useful advice within this post! It is the little changes that
    will make the most significant changes. Thanks for sharing!

  19. Hmm is anyone else having problems with the pictures on this blog
    loading? I’m trying to figure out if its a problem on my end or if it’s the blog.
    Any suggestions would be greatly appreciated.

  20. This is the perfect site for everyone who hopes to understand this topic.
    You understand so much its almost hard to argue with
    you (not that I actually would want to…HaHa). You certainly put
    a new spin on a subject that has been discussed
    for ages. Wonderful stuff, just great!

  21. An outstanding share! I’ve just forwarded this onto a colleague who was doing a little research
    on this. And he actually bought me lunch simply because I stumbled upon it for him…
    lol. So let me reword this…. Thanks for the meal!!
    But yeah, thanks for spending time to discuss this issue here on your blog.

  22. Do you have a spam issue on this blog; I also am a blogger, and I was
    curious about your situation; we have created some nice practices and we are looking to
    swap methods with other folks, please shoot me an email
    if interested.

  23. I’m gone to say to my little brother, that he should also pay a visit this webpage on regular basis to take updated from hottest information.

  24. I have been browsing online more than 3 hours today, yet I
    never found any interesting article like yours.
    It is pretty worth enough for me. In my opinion, if all
    website owners and bloggers made good content as you did, the web will be much more useful than ever before.

  25. Magnificent beat ! I wish to apprentice while you amend your web site, how could i subscribe
    for a weblog web site? The account helped me a applicable deal.
    I have been tiny bit familiar of this your broadcast provided vivid transparent concept

  26. great post, very informative. I ponder why the other specialists
    of this sector do not notice this. You should continue your writing.
    I am sure, you have a great readers’ base already!

  27. I just like the valuable info you supply for your articles.
    I’ll bookmark your blog and test once more here frequently.
    I’m reasonably certain I’ll be told many new stuff proper right here!
    Good luck for the next!

  28. Thank you for the good writeup. It in fact was a amusement account it.
    Look advanced to more added agreeable from you! However, how can we communicate?

  29. Howdy! This blog post could not be written much better! Looking through this post reminds me of my previous roommate!
    He continually kept preaching about this.
    I will send this article to him. Pretty sure he’s going to have a very good read.
    Thank you for sharing!

  30. This design is incredible! You obviously know how to keep a reader amused.

    Between your wit and your videos, I was almost moved
    to start my own blog (well, almost…HaHa!) Wonderful job.
    I really enjoyed what you had to say, and more than that, how you
    presented it. Too cool!

Leave a Reply

Your email address will not be published. Required fields are marked *