A Prototype Therapy System for Boiling Histotripsy in Abdominal Targets Based on a 256-Element Spiral Array

Bawiec, Christopher R.; Khokhlova, Tatiana D.; Sapozhnikov, Oleg A.; Rosnitskiy, Pavel B.; Cunitz, Bryan W.; Ghanem, Mohamed A.; Hunter, Christopher; Kreider, Wayne; Schade, George R.; Yuldashev, Petr V.; Khokhlova, Vera A.

doi:10.1109/tuffc.2020.3036580

Cited by 26 publications

(4 citation statements)

References 47 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Histotripsy is a well-characterized method, and existing literature contains many examples of histotripsy. − , The high energy used in histotripsy is well above the MI, and therefore the US focus will fractionate any tissue that it will encounter. Patient movement as a result of breathing is a challenge that can cause damage to healthy tissues near the focal spot.…”

Section: Discussionmentioning

confidence: 99%

“…Respiration-motion can lead to incomplete ablation or collateral damage and considerably alter precision and efficacy . Further, the need to fabricate high intensity focused transducers and the technological challenges associated with it are yet another limitation . In an effort to reduce the pressure threshold required for histotripsy, the combination of histotripsy with microbubbles (MB) or nanodroplets was proposed; however, in the megahertz US range, the combination resulted in a 2- to 3-fold reduction in the onset pressure to ∼10 MPa, which is still a high pressure. − The combination was also proposed in the context of brain therapy and the creation of spine injury models. , In this paper, we developed a therapeutic platform for low-energy, minimally invasive, US surgery of tumors using MBs, with an order of magnitude reduction in the required pressure compared to standard histotripsy (Figure ).…”

Section: Introductionmentioning

confidence: 99%

“…16 Further, the need to fabricate high intensity focused transducers and the technological challenges associated with it are yet another limitation. 18 In an effort to reduce the pressure threshold required for histotripsy, the combination of histotripsy with microbubbles (MB) or nanodroplets was proposed; however, in the megahertz US range, the combination resulted in a 2-to 3-fold reduction in the onset pressure to ∼10 MPa, which is still a high pressure. 19−23 The combination was also proposed in the context of brain therapy and the creation of spine injury models.…”

Section: ■ Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Acoustically Detonated Microbubbles Coupled with Low Frequency Insonation: Multiparameter Evaluation of Low Energy Mechanical Ablation

et al. 2021

View full text Add to dashboard Cite

Noninvasive ultrasound surgery can be achieved using focused ultrasound to locally affect the targeted site without damaging intervening tissues. Mechanical ablation and histotripsy use short and intense acoustic pulses to destroy the tissue via a purely mechanical effect. Here, we show that coupled with low-frequency excitation, targeted microbubbles can serve as mechanical therapeutic warheads that trigger potent mechanical effects in tumors using focused ultrasound. Upon low frequency excitation (250 kHz and below), high amplitude microbubble oscillations occur at substantially lower pressures as compared to higher MHz ultrasonic frequencies. For example, inertial cavitation was initiated at a pressure of 75 kPa for a center frequency of 80 kHz. Low frequency insonation of targeted microbubbles was then used to achieve low energy tumor cell fractionation at pressures below a mechanical index of 1.9, and in accordance with the Food and Drug Administration guidelines. We demonstrate these capabilities in vitro and in vivo. In cell cultures, cell viability was reduced to 16% at a peak negative pressure of 800 kPa at the 250 kHz frequency (mechanical index of 1.6) and to 10% at a peak negative pressure of 250 kPa at a frequency of 80 kHz (mechanical index of 0.9). Following an intratumoral injection of targeted microbubbles into tumor-bearing mice, and coupled with low frequency ultrasound application, significant tumor debulking and cancer cell death was observed. Our findings suggest that reducing the center frequency enhances microbubble-mediated mechanical ablation; thus, this technology provides a unique theranostic platform for safe low energy tumor fractionation, while reducing off-target effects.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: ■ Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Acoustically Detonated Microbubbles Coupled with Low Frequency Insonation: Multiparameter Evaluation of Low Energy Mechanical Ablation

et al. 2021

View full text Add to dashboard Cite

show abstract

“…Several tFUS technologies have been developed to overcome the skull-induced beam aberration. The most commonly used approach is to utilize phased arrays, which focus the ultrasound beam at the desired target by modulating the phase delay of each independent transducer element ( Deng et al, 2020 ; Sukovich et al, 2020 ; Adams et al, 2021 ; Bawiec et al, 2021 ; Leung et al, 2021 ). Although phased arrays have the advantage of being dynamically programmable, these arrays need a large number of transducer elements and complex electronics ( Melde et al, 2016 ).…”

Section: Introductionmentioning

confidence: 99%

Binary acoustic metasurfaces for dynamic focusing of transcranial ultrasound

Yang

et al. 2022

Front. Neurosci.

View full text Add to dashboard Cite

Transcranial focused ultrasound (tFUS) is a promising technique for non-invasive and spatially targeted neuromodulation and treatment of brain diseases. Acoustic lenses were designed to correct the skull-induced beam aberration, but these designs could only generate static focused ultrasound beams inside the brain. Here, we designed and 3D printed binary acoustic metasurfaces (BAMs) for skull aberration correction and dynamic ultrasound beam focusing. BAMs were designed by binarizing the phase distribution at the surface of the metasurfaces. The phase distribution was calculated based on time reversal to correct the skull-induced phase aberration. The binarization enabled the ultrasound beam to be dynamically steered along wave propagation direction by adjusting the operation frequency of the incident ultrasound wave. The designed BAMs were manufactured by 3D printing with two coding bits, a polylactic acid unit for bit “1” and a water unit for bit “0.” BAMs for single- and multi-point focusing through the human skull were designed, 3D printed, and validated numerically and experimentally. The proposed BAMs with subwavelength scale in thickness are simple to design, easy to fabric, and capable of correcting skull aberration and achieving dynamic beam steering.

show abstract