The 61st IEEE International Ultrasonics Symposium (IEEE IUS) convened in Montreal, Quebec, Canada, from September 3–8, 2023, drawing over 1,500 attendees to discuss innovations in ultrasonics. This included advancements in health care, materials science, and engineering. The conference served as a key venue for researchers, engineers, and practitioners to share findings and collaborate. This report highlights key discussions and presentations relevant to focused ultrasound, with a particular focus on A Cmut Probe For Ultrasound-guided Focused Ultrasound Targeted Therapy.
Focused Ultrasound Developments
The conference featured multiple sessions dedicated to therapeutic ultrasound, including approximately 600 posters showcasing research. Key areas of focus within therapeutic ultrasound included targeted drug delivery, tissue ablation, and noninvasive treatments. Presentations focused on optimizing treatment protocols, enhancing targeting accuracy, and reducing side effects.
The event also explored emerging trends such as integrating artificial intelligence (AI) and machine learning for data analysis, developing miniaturized devices for point-of-care diagnostics, and innovating transducer materials and fabrication methods. These advancements aim to improve the precision and efficacy of ultrasound therapies.
Key Presentations and Short Courses
Elisa Konofagou, PhD, co-chaired the meeting, and Nir Lipsman, MD, PhD, presented an invited talk titled, “MR-Guided Focused Ultrasound in the Human Brain: Lessons Learned from Early Clinical Trials.” This presentation shared insights from clinical trials using MR-guided focused ultrasound in the brain.
Meaghan O’Reilly, PhD, and David Melodelima, PhD, led a short course titled, “Therapeutic Applications of Focused Ultrasound: From Biophysics to Clinical Application.” This course provided an overview of the biophysics underlying focused ultrasound and its clinical applications.
Additional Short Courses
- Therapeutic Applications of Focused Ultrasound: From Biophysics to Clinical Application by Meaghan O’Reilly and David Melodelima
- Hydrophone Measurements for Biomedical Ultrasound Applications by Andrew Hurrell, Sam Howard, Peter Lewin, Srinath Rajagopal, Keith Wear, and Volker Wilkins.
Further details on these short courses can be found at the IEEE IUS website.
Lectures of Interest
Several lectures focused on therapeutic applications and advancements in ultrasound technology.
Session A1L-03: MCA: Therapy and Drug Delivery
This session included discussions on optical and acoustic investigations of bubble behavior under therapeutic ultrasound conditions and intravital imaging of focused ultrasound–stimulated nanodroplets in tumor microvasculature.
Session A3L-03: MTN: Theranostic Treatment Monitoring
Presentations covered the assessment of focused ultrasound-induced thermal lesion size using multi-frequency single transducer harmonic motion imaging and monitoring tissue coagulation with pulse inversion shear wave elastography.
Session A5L-01: Invited Session: Advances in Clinical Ultrasound
Nir Lipsman discussed lessons learned from early clinical trials of MR-guided focused ultrasound in the human brain.
Session A5L-03: MTH: Cavitation Based Therapy
This session explored degrading blood clots by histotripsy, volumetric nanodroplets-enhanced ultrasound surgery combined with immunotherapy, ultrasonic cavitation–enhanced stem cells transplantation, grey and white matter focused ultrasound–mediated blood-brain barrier opening, and transcriptomic investigation of bioeffects from microbubble and focused ultrasound–assisted blood-brain barrier disruption.
Session B1L-03: MTH: Drug Delivery
Presentations included ultrasound-enhanced delivery of Urolithin A, focused acoustic vortex–mediated sonochemotherapy, evaluation of immune activation of drug-loaded oxygen microbubbles, LIPUS promoting nanoparticle absorption for tissue elasticity recovery, and noninvasive pulsed ultrasound–enhanced exogenous nucleic acid delivery.
Session B1L-05: PGP: General Physical Acoustics II
This session discussed passive and active cavitation detection methods.
Session B3L-03: MBE: Stimulatory and Therapeutic Bioeffects
Lectures covered focused ultrasound–mediated effects on the blood–cerebrospinal fluid barrier, low-intensity pulsed ultrasound stimulation as a disruptive liquid biopsy approach, in vivo two-photon microscopy imaging of focused ultrasound–mediated glymphatic transportation, induction of a torpor-like hypothermic state using ultrasound, and histotripsy immunotherapy combination for the treatment of murine pancreatic tumors.
Session B3L-07: TMU: Capacitive Micromachined Ultrasonic Transducers
A key presentation in this session focused on experimental validation of a dual-mode ultrasound-guided HIFU (USgHIFU) CMUT probe developed for targeted endocavitary focal therapies. This highlights the ongoing advancements in probe technology for precise therapeutic applications.
Session B4L-03: MTH: Neuromodulation
This session explored high-throughput ultrasound neuromodulation, non-invasive ultrasound stimulation of the sciatic nerve for pain treatment, displacement and cavitation monitoring during focused ultrasound neuromodulation, investigation of hemodynamic responses induced by focused ultrasound stimulation, and exploration of biomechanisms regulating single-pulse focused ultrasound–evoked Ca2+ signaling.
Session B6L-03: MTN: Image-Guided Theranostics
Presentations covered evaluating the accuracy of blood-brain barrier opening, first-in-human prospective trial of sonobiopsy in glioblastoma patients, combination of lateral beam steering and axial focusing for blood-brain barrier opening, real-time guidance of transcranial focused ultrasound exposure, and a single linear array for simultaneous blood-brain barrier opening and cavitation mapping.
Session C1L-07: MSD: Systems for Imaging and Therapy Monitoring
This session discussed passive acoustic detection systems for focused ultrasound device quality assurance and treatment monitoring.
Session C3L-03: MPA: Imaging Therapy
Presentations covered ultrasound and photoacoustic image-guided micro-histotripsy for non-invasive surgery.
Session C4L-01: MBB: Novel Beamforming Approaches
This session focused on ultrasound monitoring of simultaneous high-intensity focused ultrasound therapy.
Session C4L-03: MTN: Novel Theranostic Agents
A presentation highlighted results from a prospective phase I clinical trial of MR-guided focused ultrasound stimulated microbubbles treatment for breast cancer.
Session C6L-07: TTT: Miniaturized Therapeutic and Interventional Ultrasound Transducers
Presentations included the acoustic lightsaber, an 8-mm endoscope with high-resolution imaging and electronically rasterized histotripsy.
Session D2L-04: NAI: Acoustic Imaging and Microscopy
This session discussed a focused ultrasound spectroscopic study on the effects of local mechanical stimulation on living cells.
Session D2L-07: MTH: Therapy Devices
Presentations included intra-operative high intensity focused ultrasound in patients with colorectal liver metastases, focused ultrasound hyperthermia mediated control of thermal responsive Car T cell activity, low-intensity pulsed ultrasound attenuating body weight and insulin resistance, in vivo intraoperative HIFU ablation of the pancreas, focused ultrasound ablation of uterine fibroids, and hologram-assisted bilateral blood-brain barrier opening.
Posters of Interest
Numerous posters presented at the symposium covered a wide range of topics related to focused ultrasound.
Session A2P-09: MBE-P: LIPUS and Neuro
Posters included research on low-intensity pulsed ultrasound improving cognitive performance in AD mice, LIPUS alleviating muscle atrophy, and focused ultrasound blood-brain barrier opening altering the murine microbiome.
Session A2P-21: MTH-P: Therapy I
This session included posters on mechanisms limiting bubble density in cavitation clouds, multi-modal confirmation of thermosensitive liposome delivery, development of optically transparent histotripsy phantoms, shockwave evolutions during volumetric histotripsy treatment, time-resolved passive acoustic mapping in transcranial histotripsy, histotripsy-induced fractionation in collagenous tissues, assessment of histotripsy and thrombolytic in a porcine model of venous thrombosis, and MRI-guided focused ultrasound blood-brain barrier opening increasing drug delivery in a glioma mouse model.
Session A2P-22: MTH-P: Therapy II
Posters covered focused ultrasound-mediated brain drug delivery, ultrasound-activated eradication of root canal biofilm, optimization of in vitro sonoporation protocol, evaluation of BBB permeability induced by focused ultrasound, focused ultrasound–mediated blood-brain barrier opening for lipid nanoparticle delivery, evaluation of ultrasound-triggered vancomycin release, double emulsion perfluorocarbon nanodroplets for US/Pa-guided drug delivery, focused ultrasound–mediated delivery of anti-PD-L1 antibody to the brain, and enhanced ultrasound neurostimulation using piezoelectric molybdenum disulfide nanosheets.
Session A2P-23: MTN-P: Treatment Monitoring
This session included posters on ultrasonic Nakagami imaging for monitoring histotripsy-inducing tissue erosion, monitoring continuous HIFU therapy, phase modulation-based harmonic suppression in CMUT transmitters, and doppler-based assessment of boiling histotripsy progression.
Session B2P-08: MBB-P: Adaptive and 3D Beamforming
Posters discussed evaluation of advanced passive acoustic mapping beamformers for high-duty-cycle HIFU.
Session B2P-09: MBE-P: Mechanisms and Dosimetry
Research included blood biopsy-based screening of prostate cancer via detection of high-intensity focused ultrasound–induced release of miRNA.
Session B2P-22: MTH-P: Therapy III
A poster focused on focused ultrasound fracture of calcified atherosclerotic plaque.
Session B2P-23: MTN-P: Theranostic Agents
Posters covered enhanced delivery of antidepressant-liposome-loaded microbubbles and measuring MRI signal of Gd-labeled antibodies for confirming ultrasound-mediated delivery into the brain.
Session C2P-10: MCA-P: PAM and Microbubble Production
This session included passive cavitation imaging using Pth root delay add sum beamforming for histotripsy guidance.
Session C2P-12: MEL-P: Advances in Elastography Methods
A poster presented passive elastography using a CMUT-based device developed for endocavitary ultrasound-guided HIFU.
Session C2P-15: MIM-P: US Simulations and US-based Modeling
This session discussed evaluation of HIFU focus prediction using acoustic radiation force imaging.
Session C2P-22: MTH-P: Therapy IV
Posters included boundary recognition of HIFU lesions, measurement of HIFU pressures, MR-guided rodent histotripsy system, a nine-French dual-mode catheter for interstitial ultrasound-guided directional HIFU, and assessment of focused ultrasound drug delivery efficacy in brain tumors with liquid biopsy.
Session C2P-23: MTN-P: Image Guidance
Presentations covered high-intensity focused ultrasound ablation monitoring using ultrafast Doppler imaging, real-time thermal strain imaging for guidance and monitoring of HIFU treatment, and low-intensity pulsed ultrasound accelerating glucose uptake in skeletal muscle.
Session C2P-32: TMI-P: Biomedical Transducers
This session included transcranial focused ultrasound stimulation of periaqueductal gray for analgesia.
Student Paper Competition
Matthew Mallay from Dalhousie University, Canada, presented “The Acoustic Lightsaber: An 8-mm Endoscope with High-Resolution Imaging and Electronically Rasterized Histotripsy.”
Conclusion
The 61st IEEE International Ultrasonics Symposium showcased significant advancements in ultrasound technology and its therapeutic applications. Discussions on targeted drug delivery, tissue ablation, and neuromodulation highlighted the potential of focused ultrasound in treating various conditions. The presentation on a CMUT probe for ultrasound-guided focused ultrasound targeted therapy exemplifies the ongoing innovations aimed at improving the precision and efficacy of ultrasound-based treatments.
Next Meeting
The IEEE Ultrasonics, Ferroelectrics, and Frequency Control (UFFC) Joint Symposium will take place September 22–26, 2024, in Taipei, Taiwan.
