High performance computing for linear acoustic wave simulation

Butt, Fouad

doi:10.32920/ryerson.14662569

“…As the model consists of several physics modules, each is compared separately with the previously published experimental or computational results to confirm the accuracy of numerical calculation and computational approach. As shown in Figure 5(a) and (b) , we first compared our results for a geometry filled with water to LATS, a previously developed accurate software for linear acoustic and thermal simulations (Butt, 2011 ; Butt et al., 2011 ; Shaswary et al., 2021 ). Results show excellent agreement (with roughly a 1.33% discrepancy).…”

Section: Validation Of the Computational Modelmentioning

confidence: 99%

A spatiotemporal computational model of focused ultrasound heat-induced nano-sized drug delivery system in solid tumors

Kashkooli

¹

,

Souri²,

Tavakkoli

³

et al. 2023

View full text Add to dashboard Cite

Focused Ultrasound (FUS)-triggered nano-sized drug delivery, as a smart stimuli-responsive system for treating solid tumors, is computationally investigated to enhance localized delivery of drug and treatment efficacy. Integration of thermosensitive liposome (TSL), as a doxorubicin (DOX)-loaded nanocarrier, and FUS, provides a promising drug delivery system. A fully coupled partial differential system of equations, including the Helmholtz equation for FUS propagation, bio-heat transfer, interstitial fluid flow, drug transport in tissue and cellular spaces, and a pharmacodynamic model is first presented for this treatment approach. Equations are then solved by finite element methods to calculate intracellular drug concentration and treatment efficacy. The main objective of this study is to present a multi-physics and multi-scale model to simulate drug release, transport, and delivery to solid tumors, followed by an analysis of how FUS exposure time and drug release rate affect these processes. Our findings not only show the capability of model to replicate this therapeutic approach, but also confirm the benefits of this treatment with an improvement of drug aggregation in tumor and reduction of drug delivery in healthy tissue. For instance, the survival fraction of tumor cells after this treatment dropped to 62.4%, because of a large amount of delivered drugs to cancer cells. Next, a combination of three release rates (ultrafast, fast, and slow) and FUS exposure times (10, 30, and 60 min) was examined. Area under curve (AUC) results show that the combination of 30 min FUS exposure and rapid drug release leads to a practical and effective therapeutic response.

show abstract

“…Further, LATS (Linear Acoustic and Temperature Simulator), an acoustic field simulation tool, previously developed in our lab (Butt and Tavakkoli, 2011) was used to simulate acoustic field generated by pHIFU transducer to obtain 2D acoustic pressure and intensity profiles at the focal point.…”

Section: Imagej Image Processing Toolmentioning

confidence: 99%

“…As shown in Figure 2.12, simulating transducer's geometry using LATS, a detailed 1-D and 2-D pressure and intensity profiles can be obtained at its focal point. The Rayleigh-Sommerfield diffraction integral (Eq (2.1)) in frequency domain is used to determine the Laplace transform of velocity potential Φ(r,s) at an external field point P located in a homogeneous, isotropic, non-dissipative medium for a source vibrating with uniform velocity in xy-plane at a distance of r from the origin (Butt and Tavakkoli, 2011). Here integration is performed over surface S. Vn is particle velocity perpendicular to the transducer surface, R is the spatial distance of external point from an infinitesimal element dS and ro is the distance of dS from the origin.…”

Section: 32a Acoustic Field Simulationsmentioning

confidence: 99%

“…Here integration is performed over surface S. Vn is particle velocity perpendicular to the transducer surface, R is the spatial distance of external point from an infinitesimal element dS and ro is the distance of dS from the origin. c is the speed of sound in medium Further, acoustic pressure can be approximated by dividing the source into small incremental areas and doing summation of all individual pressures generated by them (Butt & Tavakkoli, 2011):…”

Section: 32a Acoustic Field Simulationsmentioning

confidence: 99%

See 1 more Smart Citation

Use of pulsed high intensity focused ultrasound to study the response of brain endothelial cells to mechanical injury

Kaur

2023

Preprint

0

View full text Add to dashboard Cite

<p>This work investigated the significance of a sublethal primary mechanical injury induced by pulsed high intensity focused ultrasound (pHIFU) and mechanical stretching techniques to mouse brain endothelial cell (bEND.3) nuclei in vitro followed by secondary hypoxia. The lateral size of the pHIFU beam’s focal spot (~ 1.7 mm) was obtained by characterizing the pHIFU system, and the transparency of the membrane on which the cells were to be cultured was determined theoretically and experimentally. Preliminary assessment of injury using a MTT assay (3-(4,5dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) at high acoustic pressures (3.15 MPa and 1.04 MPa for 50 ms) demonstrated cell damage. In the subsequent experiments, the cells were sublethally exposed to either pHIFU (0.57 MPa for 50ms) or stretch injuries (0.012 – 0.014 MPa for 50 ms). After each primary injury, the cells were either fully normoxic for 24 h or were subjected to a 6 h hypoxic environment followed by an 18 h recovery under normoxic conditions. The morphological parameters (area and circularity) of bEND.3 nuclei post-treatment were measured using an image analysis tool (ImageJ) for three primary treatments (control, pHIFU and stretch) and evaluated by plotting the scatterplots. Compared to the control group, a statistically significant decrease in circularity of bEND.3 nuclei was observed when the cells were subjected to 6 h hypoxia following a primary injury whereas nuclear area remained unchanged. The percentage of deformed nuclei also increased to ~ 19 % for pHIFU and stretch injury groups after 18 h normoxia following primary and secondary insult (6 h hypoxia), demonstrating cells’ inability to recover due to injury. However, when this hypoxic-normoxic regimen was not preceded by a pHIFU (or mechanical stretch) primary injury, nuclei recovered their original shape successfully. In conclusion, as shown in this study, cells became more susceptible to secondary hypoxic injury after being exposed to an initial mechanical insult. </p>

show abstract

“…Further, LATS (Linear Acoustic and Temperature Simulator), an acoustic field simulation tool, previously developed in our lab (Butt and Tavakkoli, 2011) was used to simulate acoustic field generated by pHIFU transducer to obtain 2D acoustic pressure and intensity profiles at the focal point.…”

Section: Imagej Image Processing Toolmentioning

confidence: 99%

Use of pulsed high intensity focused ultrasound to study the response of brain endothelial cells to mechanical injury

Kaur

2023

Preprint

0

View full text Add to dashboard Cite

<p>This work investigated the significance of a sublethal primary mechanical injury induced by pulsed high intensity focused ultrasound (pHIFU) and mechanical stretching techniques to mouse brain endothelial cell (bEND.3) nuclei in vitro followed by secondary hypoxia. The lateral size of the pHIFU beam’s focal spot (~ 1.7 mm) was obtained by characterizing the pHIFU system, and the transparency of the membrane on which the cells were to be cultured was determined theoretically and experimentally. Preliminary assessment of injury using a MTT assay (3-(4,5dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) at high acoustic pressures (3.15 MPa and 1.04 MPa for 50 ms) demonstrated cell damage. In the subsequent experiments, the cells were sublethally exposed to either pHIFU (0.57 MPa for 50ms) or stretch injuries (0.012 – 0.014 MPa for 50 ms). After each primary injury, the cells were either fully normoxic for 24 h or were subjected to a 6 h hypoxic environment followed by an 18 h recovery under normoxic conditions. The morphological parameters (area and circularity) of bEND.3 nuclei post-treatment were measured using an image analysis tool (ImageJ) for three primary treatments (control, pHIFU and stretch) and evaluated by plotting the scatterplots. Compared to the control group, a statistically significant decrease in circularity of bEND.3 nuclei was observed when the cells were subjected to 6 h hypoxia following a primary injury whereas nuclear area remained unchanged. The percentage of deformed nuclei also increased to ~ 19 % for pHIFU and stretch injury groups after 18 h normoxia following primary and secondary insult (6 h hypoxia), demonstrating cells’ inability to recover due to injury. However, when this hypoxic-normoxic regimen was not preceded by a pHIFU (or mechanical stretch) primary injury, nuclei recovered their original shape successfully. In conclusion, as shown in this study, cells became more susceptible to secondary hypoxic injury after being exposed to an initial mechanical insult. </p>

show abstract

High performance computing for linear acoustic wave simulation

Cited by 3 publications

References 13 publications

A spatiotemporal computational model of focused ultrasound heat-induced nano-sized drug delivery system in solid tumors

A spatiotemporal computational model of focused ultrasound heat-induced nano-sized drug delivery system in solid tumors

Use of pulsed high intensity focused ultrasound to study the response of brain endothelial cells to mechanical injury

Use of pulsed high intensity focused ultrasound to study the response of brain endothelial cells to mechanical injury

Contact Info

Product

Resources

About