Kasra Naftchi-Ardebili
Postdoctoral Scholar, Anesthesiology, Perioperative and Pain Medicine
Professional Education
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Bachelor of Arts, University of Chicago (2012)
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Doctor of Philosophy, Stanford University, BIOE-PHD (2025)
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Master of Science, Stanford University, BIOE-MS (2021)
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MS, University of California, San Diego, Bioengineering (2017)
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BS, The University of Chicago, Biochemistry (2012)
All Publications
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A deep-learning model for one-shot transcranial ultrasound simulation and phase aberration correction.
Medical physics
2026; 53 (1): e70259
Abstract
Transcranial ultrasound is a promising non-invasive neuromodulation technique with applications, including neuronal activity modulation, blood-brain barrier opening, targeted drug delivery, and thermal ablation. Its ability to deliver focused ultrasound waves to precise brain regions has led to over 50 clinical trials targeting conditions such as opioid addiction, Alzheimer's disease, dementia, epilepsy, and glioblastoma. However, skull heterogeneity complicates accurate focal spot prediction and energy delivery, requiring rapid yet precise phase aberration correction in clinical workflows.To address the trade-off between computational efficiency and accuracy in current focus prediction methods, we introduce TUSNet, a deep learning framework for rapid and accurate transcranial ultrasound pressure field and phase aberration correction computation.TUSNet, an end-to-end neural network, was trained to predict both 2D transcranial ultrasound pressure fields and phase corrections. TUSNet was trained on 180432 synthetic skull Computed Tomography (CT) segments, and tested on 1232 real skull CT segments. Its performance was benchmarked against k-Wave, a MATLAB-based acoustic simulation package, evaluating computation speed, focal spot accuracy, phase correction accuracy, and pressure magnitude estimation.TUSNet computed pressure fields and phase corrections in 21 ms, which is over 1200 × $\times$ faster than k-Wave, while achieving 98.3% accuracy in peak pressure magnitude estimation and a mean focal positioning error of only 0.18 mm relative to k-Wave ground truth. End-to-end training took approximately 8 h on 4x NVIDIA A100 80 GB GPUs.TUSNet demonstrates that deep learning can provide accurate and rapid estimates of phase aberrations and transcranial pressure fields, offering a promising direction for accelerating ultrasound treatment planning. While the present validation is based on simulated, noise-free ultrasound fields, the results establish a foundation that future experimental studies can build on to assess performance under real-world clinical conditions.
View details for DOI 10.1002/mp.70259
View details for PubMedID 41474058
View details for PubMedCentralID PMC12754752
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Biophysical effects and neuromodulatory dose of transcranial ultrasonic stimulation.
Brain stimulation
2025
Abstract
Transcranial ultrasonic stimulation (TUS) has the potential to usher in a new era for human neuroscience by allowing spatially precise and high-resolution non-invasive targeting of both deep and superficial brain regions. Currently, fundamental research on the mechanisms of interaction between ultrasound and neural tissues is progressing in parallel with application-focused research. However, a major hurdle in the wider use of TUS is the selection of optimal parameters to enable safe and effective neuromodulation in humans. In this paper, we will discuss the major factors that determine the efficacy of TUS. We will discuss the thermal and mechanical biophysical effects of ultrasound, which underlie its biological effects, in the context of their relationships with tunable parameters. Based on this knowledge of biophysical effects, and drawing on concepts from radiotherapy, we propose a framework for conceptualising TUS dose.
View details for DOI 10.1016/j.brs.2025.02.019
View details for PubMedID 40054576
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Focal Volume, Acoustic Radiation Force, and Strain in Two-Transducer Regimes
IEEE TRANSACTIONS ON ULTRASONICS FERROELECTRICS AND FREQUENCY CONTROL
2024; 71 (10): 1199-1216
Abstract
Transcranial ultrasound stimulation (TUS) holds promise for noninvasive neural modulation in treating neurological disorders. Most clinically relevant targets are deep within the brain (near or at its geometric center), surrounded by other sensitive regions that need to be spared clinical intervention. However, in TUS, increasing frequency with the goal of improving spatial resolution reduces the effective penetration depth. We show that by using a pair of 1-MHz orthogonally arranged transducers, we improve the spatial resolution afforded by each of the transducers individually, by nearly 40 folds, achieving a subcubic millimeter target volume of [Formula: see text]. We show that orthogonally placed transducers generate highly localized standing waves with acoustic radiation force (ARF) arranged into periodic regions of compression and tension near the target. We further present an extended capability of the orthogonal setup, which is to impart selective pressures-either positive or negative, but not both-on the target. Finally, we share our preliminary findings that strain can arise from both particle motion (PM) and ARF with the former reaching its maximum value at the focus and the latter remaining null at the focus and reaching its maximum around the focus. As the field is investigating the mechanism of interaction in TUS by way of elucidating the mapping between ultrasound parameters and neural response, orthogonal transducers expand our toolbox by making it possible to conduct these investigations at much finer spatial resolutions, with localized and directed (compression versus tension) ARF and the capability of applying selective pressures at the target.
View details for DOI 10.1109/TUFFC.2024.3456048
View details for Web of Science ID 001338565700012
View details for PubMedID 39240744
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Biophysical effects and neuromodulatory dose of transcranial ultrasonic stimulation.
ArXiv
2024
Abstract
Transcranial ultrasonic stimulation (TUS) has the potential to usher in a new era for human neuroscience by allowing spatially precise and high-resolution non-invasive targeting of both deep and superficial brain regions. Currently, fundamental research on the mechanisms of interaction between ultrasound and neural tissues is progressing in parallel with application-focused research. However, a major hurdle in the wider use of TUS is the selection of optimal parameters to enable safe and effective neuromodulation in humans. In this paper, we will discuss the major factors that determine both the safety and efficacy of TUS. We will discuss the thermal and mechanical biophysical effects of ultrasound, which underlie its biological effects, in the context of their relationships with tunable parameters. Based on this knowledge of biophysical effects, and drawing on concepts from radiotherapy, we propose a framework for conceptualising TUS dose.
View details for PubMedID 39010872
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Rank restriction for the variational calculation of two-electron reduced density matrices of many-electron atoms and molecules
PHYSICAL REVIEW A
2011; 84 (5)
View details for DOI 10.1103/PhysRevA.84.052506
View details for Web of Science ID 000296850500003