Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Article
  • Published:

A conformable phased-array ultrasound patch for bladder volume monitoring

Nature Electronics volume 7, pages 77–90 (2024)Cite this article

Subjects

A Publisher Correction to this article was published on 27 November 2023

This article has been updated

Abstract

Ultrasound can be used to image soft tissues in vivo for the early diagnosis and monitoring of disease progression. However, conventional ultrasound probes are rigid, have a narrow field of view and are operator dependent. Conformable transducers have been proposed, but they lack efficient element localization and effective spatial resolution during mechanical deformations. Here we report a conformable ultrasound bladder patch that is based on multiple phased arrays embedded in a stretchable substrate and can provide mechanically robust, conformable and in vivo volumetric organ monitoring. The phased arrays use Sm/La-doped Pb(Mg1/3Nb2/3)O3–PbTiO3 ceramics as the piezoelectric material, which offers superior properties (d33 = 1,000 pC N−1, εr = 7,500 and k33 = 0.77) than conventional piezoelectric ceramics. We use the conformable ultrasound patch in a pilot clinical study of bladder monitoring. Bladder volume estimation with the patch is comparable (relative errors of 3.2 ± 6.4% and 10.8 ± 8.2% with and without ultrasound gel, respectively) to that obtained using standard clinical ultrasound equipment, and not requiring manual translation or rotation by an operator.

This is a preview of subscription content, access via your institution

Access options

Buy this article

  • Purchase on Springer Link
  • Instant access to full article PDF
Buy now

Prices may be subject to local taxes which are calculated during checkout

Fig. 1: Overview of the phased array and cUSB-Patch.
Fig. 2: Characterization of morphological, piezoelectric and dielectric properties of Sm/La-PMN-xPT ceramics.
Fig. 3: Piezoelectric and acoustic performances of phased-array transducers.
Fig. 4: Real-time ultrasound imaging by the C5-2v commercial probe and the cUSB-Patch on the oval phantom.
Fig. 5: Real-time ultrasound imaging on the bladders of different subjects.
Fig. 6: Summary and comparison of the calculated bladder volumes of four subjects.

Similar content being viewed by others

Data availability

The raw data from human trials are available from the corresponding author, subject to approval from The Mass General Brigham IRB (#2021P001706). All other data that support the findings of this study are available from the corresponding author upon reasonable request.

Code availability

The codes based on Python used for the synthetic array beamforming, simulation and image analysis are available from the corresponding author on reasonable request.

Change history

References

  1. Dagdeviren, C. et al. Recent progress in flexible and stretchable piezoelectric devices for mechanical energy harvesting, sensing and actuation. Extrem. Mech. Lett. 9, 269–281 (2016).

    Article  Google Scholar 

  2. Wang, C., Wang, C., Huang, Z. & Xu, S. Materials and structures toward soft electronics. Adv. Mater. 30, 1801368 (2018).

    Article  Google Scholar 

  3. Fernandez, S. V. et al. On-body piezoelectric energy harvesters through innovative designs and conformable structures. ACS Biomater. Sci. Eng. 9, 2070–2086 (2021).

    Article  Google Scholar 

  4. Dagdeviren, C., Li, Z. & Wang, Z. L. Energy harvesting from the animal/human body for self-powered electronics. Annu. Rev. Biomed. Eng. 19, 85–108 (2017).

    Article  Google Scholar 

  5. Fernandez, S. V. et al. Ubiquitous conformable systems for imperceptible computing. Foresight 24, 75–98 (2022).

    Article  Google Scholar 

  6. Dagdeviren, C. et al. Conformal piezoelectric systems for clinical and experimental characterization of soft tissue biomechanics. Nat. Mater. 14, 728–736 (2015).

    Article  Google Scholar 

  7. Guan, Y. et al. Soft, super-elastic, all-polymer piezoelectric elastomer for artificial electronic skin. ACS Appl. Mater. Interfaces 15, 1736–1747 (2023).

    Article  Google Scholar 

  8. Dagdeviren, C. et al. Conformal piezoelectric energy harvesting and storage from motions of the heart, lung, and diaphragm. Proc. Natl Acad. Sci. USA 111, 1927–1932 (2014).

    Article  Google Scholar 

  9. Nayeem, M. O. G. et al. All-nanofiber–based, ultrasensitive, gas-permeable mechanoacoustic sensors for continuous long-term heart monitoring. Proc. Natl Acad. Sci. USA 117, 7063–7070 (2020).

    Article  Google Scholar 

  10. Sun, T. et al. Decoding of facial strains via conformable piezoelectric interfaces. Nat. Biomed. Eng. 4, 954–972 (2020).

    Article  Google Scholar 

  11. Amiri, N., Tasnim, F., Tavakkoli Anbarani, M., Dagdeviren, C. & Karami, M. A. Experimentally verified finite element modeling and analysis of a conformable piezoelectric sensor. Smart Mater. Struct. 30, 085017 (2021).

    Article  Google Scholar 

  12. Dagdeviren, C. et al. Flexible piezoelectric devices for gastrointestinal motility sensing. Nat. Biomed. Eng. 1, 807–817 (2017).

    Article  Google Scholar 

  13. Chun, S. et al. An artificial neural tactile sensing system. Nat. Electron. 4, 429–438 (2021).

    Article  Google Scholar 

  14. Dagdeviren, C. et al. Conformable amplified lead zirconate titanate sensors with enhanced piezoelectric response for cutaneous pressure monitoring. Nat. Commun. 5, 4496 (2014).

    Article  Google Scholar 

  15. Wang, C. et al. Monitoring of the central blood pressure waveform via a conformal ultrasonic device. Nat. Biomed. Eng. 2, 687–695 (2018).

    Article  Google Scholar 

  16. Wang, F. et al. Flexible Doppler ultrasound device for the monitoring of blood flow velocity. Sci. Adv. 7, eabi9283 (2021).

    Article  Google Scholar 

  17. Kim, T. et al. Flexible 1–3 composite ultrasound transducers with silver nanowire-based stretchable electrodes. IEEE Trans. Ind. Electron. 67, 6955–6962 (2019).

  18. Pashaei, V. et al. Flexible body-conformal ultrasound patches for image-guided neuromodulation. IEEE Trans. Biomed. Circuits Syst. 14, 305–318 (2020).

    Article  Google Scholar 

  19. Sadeghpour, S., Lips, B., Kraft, M. & Puers, R. Bendable piezoelectric micromachined ultrasound transducer (PMUT) arrays based on silicon-on-insulator (SOI) technology. J. Microelectromech. Syst. 29, 378–386 (2020).

  20. Wang, C. et al. Continuous monitoring of deep-tissue haemodynamics with stretchable ultrasonic phased arrays. Nat. Biomed. Eng. 5, 749–758 (2021).

    Article  Google Scholar 

  21. Liu, W., Chen, W., Zhu, C. & Wu, D. Design and micromachining of a stretchable two-dimensional ultrasonic array. Micro Nano Eng. 13, 100096 (2021).

    Article  Google Scholar 

  22. Zhang, Q. et al. Transformable ultrasonic array transducer for multiscale imaging and beamforming. IEEE Trans. Ind. Electron. 69, 3078–3087 (2022).

    Article  Google Scholar 

  23. Wang, C. et al. Bioadhesive ultrasound for long-term continuous imaging of diverse organs. Science 377, 517–523 (2022).

    Article  Google Scholar 

  24. Yu, C.-C. et al. A conformable ultrasound patch for cavitation-enhanced transdermal cosmeceutical delivery. Adv. Mater. 35, 2300066 (2023).

  25. de Oliveira, T. F., Pai, C. N., Matuda, M. Y., Adamowski, J. C. & Buiochi, F. Development of a 2.25 MHz flexible array ultrasonic transducer. Res. Biomed. Eng. 35, 27–37 (2019).

    Article  Google Scholar 

  26. Du, W. et al. Conformable ultrasound breast patch for deep tissue scanning and imaging. Sci. Adv. 9, eadh5325 (2023).

    Article  Google Scholar 

  27. Hu, H. et al. A wearable cardiac ultrasound imager. Nature 613, 667–675 (2023).

    Article  Google Scholar 

  28. Hu, H. et al. Stretchable ultrasonic transducer arrays for three-dimensional imaging on complex surfaces. Sci. Adv. 4, eaar3979 (2018).

    Article  Google Scholar 

  29. Yang, Y. et al. A flexible piezoelectric micromachined ultrasound transducer. RSC Adv. 3, 24900–24905 (2013).

    Article  Google Scholar 

  30. Zhu, Q. et al. A piezoelectric micro-machined ultrasonic transducer array based on flexible substrate. In Proc. 13th Annual IEEE International Conference on Nano/Micro Engineered and Molecular Systems 345–348 (IEEE, 2018).

  31. Wang, Z. et al. A flexible ultrasound transducer array with micro-machined bulk PZT. Sensors 15, 2538–2547 (2015).

  32. Zhou, Q., Lam, K. H., Zheng, H., Qiu, W. & Shung, K. K. Piezoelectric single crystal ultrasonic transducers for biomedical applications. Prog. Mater. Sci. 66, 87–111 (2014).

    Article  Google Scholar 

  33. Li, C. et al. Atomic-scale origin of ultrahigh piezoelectricity in samarium-doped PMN-PT ceramics. Phys. Rev. B 101, 140102 (2020).

    Article  Google Scholar 

  34. Li, F. et al. Ultrahigh piezoelectricity in ferroelectric ceramics by design. Nat. Mater. 17, 349–354 (2018).

    Article  Google Scholar 

  35. Zhou, S., Lin, D., Su, Y., Zhang, L. & Liu, W. Enhanced dielectric, ferroelectric, and optical properties in rare earth elements doped PMN-PT thin films. J. Adv. Ceram. 10, 98–107 (2021).

    Article  Google Scholar 

  36. Zhang, Z. et al. New Sm-PMN-PT ceramic-based 2-D array for low-intensity ultrasound therapy application. IEEE Trans. Ultrason. Ferroelectr. Freq. Control 67, 2085–2094 (2020).

    Article  Google Scholar 

  37. Zhang, Z. et al. High-performance ultrasound needle transducer based on modified PMN-PT ceramic with ultrahigh clamped dielectric permittivity. IEEE Trans. Ultrason. Ferroelectr. Freq. Control 65, 223–230 (2018).

    Article  Google Scholar 

  38. Kristiansen, N. K., Djurhuus, J. C. & Nygaard, H. Design and evaluation of an ultrasound-based bladder volume monitor. Med. Biol. Eng. Comput. 42, 762–769 (2004).

    Article  Google Scholar 

  39. Tanaka, R. & Abe, T. Measurement of the bladder volume with a limited number of ultrasonic transducers. In 2010 IEEE International Ultrasonics Symposium 1783–1786 (IEEE, 2010).

  40. van Leuteren, P. G. et al. URIKA, continuous ultrasound monitoring for the detection of a full bladder in children with dysfunctional voiding: a feasibility study. Biomed. Phys. Eng. Express 3, 017005 (2017).

    Article  Google Scholar 

  41. Kuru, K. et al. Intelligent autonomous treatment of bedwetting using non-invasive wearable advanced mechatronics systems and MEMS sensors. Med. Biol. Eng. Comput. 58, 943–965 (2020).

    Article  Google Scholar 

  42. Kuru, K., Ansell, D., Jones, M., De Goede, C. & Leather, P. Feasibility study of intelligent autonomous determination of the bladder voiding need to treat bedwetting using ultrasound and smartphone ML techniques. Med. Biol. Eng. Comput. 57, 1079–1097 (2019).

    Article  Google Scholar 

  43. Fournelle, M. et al. Portable ultrasound research system for use in automated bladder monitoring with machine-learning-based segmentation. Sensors 21, 6481 (2021).

  44. Jo, H. G. et al. Forward-looking ultrasound wearable scanner system for estimation of urinary bladder volume. Sensors 21, 5445 (2021).

  45. Dagdeviren, C. & Zhang, L. Methods and apparatus for imaging with conformable ultrasound patch. US patent 16/658,237 (2020).

  46. Yang, J. C. et al. Geometrically engineered rigid island array for stretchable electronics capable of withstanding various deformation modes. Sci. Adv. 8, eabn3863 (2023).

    Article  Google Scholar 

  47. Fielding, J. T., Shrout, T. R. & Jang, S. J. Increased operating temperature range in La-modified Pb(Mg1/3Nb2/3)O3-PbTiO3 relaxor ferroelectric-based transducers. In Proc. 1994 IEEE International Symposium on Applications of Ferroelectrics 158–161 (IEEE, 1994).

  48. Choi, S. W., Shrout, T. R., Jang, S. J. & Bhalla, A. S. Morphotropic phase boundary in Pb (Mg13Nb23) O3-PbTiO3 system. Mater. Lett. 8, 253–255 (1989).

    Article  Google Scholar 

  49. Kim, N., Jang, S. J. & Shrout, T. R. Relaxor based fine grain piezoelectric materials. In Proc. 1990 IEEE 7th International Symposium on Applications of Ferroelectrics 605–609 (IEEE, 1990).

  50. Jiang, X.-J. et al. A microscale linear phased-array ultrasonic transducer based on PZT ceramics. Sensors 19, 1244 (2019).

    Article  Google Scholar 

  51. Bala, K. G. & Chou, Y.-H. Ultrasonography of the urinary bladder. J. Med. Ultrasound 18, 105–114 (2010).

    Article  Google Scholar 

  52. Bih, L.-I., Ho, C.-C., Tsai, S.-J., Lai, Y.-C. & Chow, W. Bladder shape impact on the accuracy of ultrasonic estimation of bladder volume. Arch. Phys. Med. Rehab. 79, 1553–1556 (1998).

    Article  Google Scholar 

Download references

Acknowledgements

C.D. thanks C. Dagdeviren and H. E. Dagdeviren for fruitful discussions throughout this project. This work was supported by the National Science Foundation CAREER: Conformable Piezoelectrics for Soft Tissue Imaging (grant no. 2044688), 3M Non-Tenured Faculty Award, Sagol Weizmann-MIT Bridge Program, Texas Instruments Inc. and MIT Media Lab Consortium funding. W.D. was supported by the National Science Foundation Graduate Research Fellowship Program (grant no. 2141064). Any opinions, findings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation. T.T.P. was supported by the 2020 ARRS Scholar Award. This work was performed in part at the Harvard University Center for Nanoscale Systems (CNS)—a member of the National Nanotechnology Coordinated Infrastructure Network (NNCI), which is supported by the National Science Foundation under NSF award no. ECCS-2025158. We thank P. Cao and C. Peng for technical discussions; H. Park and J. Tresback for assistance on microfabrication; O. Drori, A. Mamistvalov, K. Brahma and A. Benjamin for imaging discussion; E. Suh for patch design discussion; and M.-C. O’Connell, M. Martin, E. Sands and Y. Gu for assisting on the clinical study.

Author information

Author notes

  1. These authors contributed equally: Lin Zhang, Colin Marcus, Dabin Lin.

Authors and Affiliations

  1. Media Lab, Massachusetts Institute of Technology, Cambridge, MA, USA

    Lin Zhang, Colin Marcus, David Mejorado, Sara V. Fernandez, Ikra Iftekhar Shuvo, David Sadat, Wenya Du & Canan Dagdeviren

  2. Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA

    Colin Marcus & Anantha P. Chandrakasan

  3. School of Opto-electronical Engineering, Xi’an Technological University, Xi’an, China

    Dabin Lin & Weiguo Liu

  4. Center for Ultrasound Research & Translation, Department of Radiology, Massachusetts General Hospital, Boston, MA, USA

    Scott Joseph Schoen Jr, Theodore T. Pierce, Viksit Kumar, David Hunt, Qian Li, Hannah Edenbaum & Anthony E. Samir

  5. Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA

    Sara V. Fernandez

  6. Electronic Materials Research Laboratory, Key Laboratory of the Ministry of Education, School of Electronic Science and Engineering, Xi’an Jiaotong University, Xi’an, China

    Li Jin & Fei Li

  7. Faculty of Math and Computer Science, Weizmann Institute of Science, Rehovot, Israel

    Yonina C. Eldar

Authors
  1. Lin Zhang
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Colin Marcus
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Dabin Lin
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. David Mejorado
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Scott Joseph Schoen Jr
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Theodore T. Pierce
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. Viksit Kumar
    View author publications

    You can also search for this author in PubMed Google Scholar

  8. Sara V. Fernandez
    View author publications

    You can also search for this author in PubMed Google Scholar

  9. David Hunt
    View author publications

    You can also search for this author in PubMed Google Scholar

  10. Qian Li
    View author publications

    You can also search for this author in PubMed Google Scholar

  11. Ikra Iftekhar Shuvo
    View author publications

    You can also search for this author in PubMed Google Scholar

  12. David Sadat
    View author publications

    You can also search for this author in PubMed Google Scholar

  13. Wenya Du
    View author publications

    You can also search for this author in PubMed Google Scholar

  14. Hannah Edenbaum
    View author publications

    You can also search for this author in PubMed Google Scholar

  15. Li Jin
    View author publications

    You can also search for this author in PubMed Google Scholar

  16. Weiguo Liu
    View author publications

    You can also search for this author in PubMed Google Scholar

  17. Yonina C. Eldar
    View author publications

    You can also search for this author in PubMed Google Scholar

  18. Fei Li
    View author publications

    You can also search for this author in PubMed Google Scholar

  19. Anantha P. Chandrakasan
    View author publications

    You can also search for this author in PubMed Google Scholar

  20. Anthony E. Samir
    View author publications

    You can also search for this author in PubMed Google Scholar

  21. Canan Dagdeviren
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

C.D. conceived the research idea, designed the research direction and directed all the research activities. A.E.S. directed the proposed implementation of the technology and supervised the clinical study. A.P.C. contributed to the overall system architecture. L.Z. and C.D. conceived the research methodology and aims. L.Z., C.M. and C.D. designed the experiments. D.L. processed and characterized the piezoelectric ceramics. W.L. supervised the materials investigation. D.L. and L.J. studied the structure and morphology of ceramics. D.L., L.Z. and F.L. analysed the performance of the ceramics. C.D., L.Z. and D.M. designed the patch for the bladder. L.Z. designed and fabricated the ultrasound arrays. D.M. and L.Z. characterized the array and fabricated the patch. C.M. and D.M. designed the electronic circuits for data acquisition. S.J.S., assisted by V.K., conducted the coding and ultrasound signal processing for image generation by the Verasonics Vantage 256 system. L.Z., C.M., S.J.S. and D.M. conducted the in vitro ultrasound imaging. I.I.S., W.D. and S.V.F. assisted with the device characterization. V.K. coordinated the in vitro study at Mass General Hospital, and T.T.P. coordinated the in vivo study, including overseeing recruitment and scheduling (with H.E.), obtaining subject informed consent and monitoring subject safety. H.E. recruited the subjects and assisted in the clinical study. L.Z., D.M., S.J.S. and V.K. conducted the safety testing and prepared the related IRB document filings. D.H., T.T.P., L.Z. and C.M. designed the clinical-trial imaging protocols. D.H. and Q.L. performed the image acquisition of the human subject. C.M., S.J.S., T.T.P., H.E., V.K., D.H. and Q.L. executed the in vivo study and analysed the data. Y.C.E. assisted in the imaging process. W.D. and D.S. composed the layout of Supplementary Videos 1–8 and formed the videos. All authors contributed to the manuscript writing.

Corresponding author

Correspondence to Canan Dagdeviren.

Ethics declarations

Competing interests

A.P.C. is on the Board of Analog Devices. The other authors declare no competing interests.

Peer review

Peer review information

Nature Electronics thanks Yangzhi Zhu, Qifa Zhou and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

Additional information

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

Supplementary Information

Supplementary Notes 1–8, Tables 1–12, Figs. 1–64, captions for Videos 1–8 and references.

Reporting Summary

Supplementary Video 1

Patch bending, stretching and twisting.

Supplementary Video 2

Patch attaching and detaching on belly, and then cleaning.

Supplementary Video 3

Comparison of phased array with C5-2v on planar phantom without pressure.

Supplementary Video 4

Three-dimensional image reconstruction on US-18 phantom.

Supplementary Video 5

Ultrasound image of five arrays on subject A (case I with gel).

Supplementary Video 6

Ultrasound image of five arrays on subject A (case I without gel).

Supplementary Video 7

Ultrasound image of five arrays on subject A (case II with gel).

Supplementary Video 8

Ultrasound image of five arrays on subject A (case II without gel).

Rights and permissions

Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Zhang, L., Marcus, C., Lin, D. et al. A conformable phased-array ultrasound patch for bladder volume monitoring. Nat Electron 7, 77–90 (2024). https://doi.org/10.1038/s41928-023-01068-x

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/s41928-023-01068-x

Search

Advanced search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing