A5080715771- Acute Ischemic Stroke Management
- Cerebrovascular and Carotid Artery Diseases
- Advanced NMR Techniques and Applications
- Stroke Rehabilitation and Recovery
- Advanced MRI Techniques and Applications
- Peripheral Artery Disease Management
- Medical Imaging Techniques and Applications
- Intracranial Aneurysms: Treatment and Complications
- Radiomics and Machine Learning in Medical Imaging
- Electron Spin Resonance Studies
- 3D Printing in Biomedical Research
- Enzyme Structure and Function
- Microfluidic and Capillary Electrophoresis Applications
- Boron Compounds in Chemistry
- Nanoplatforms for cancer theranostics
- Nuclear Physics and Applications
- Metastasis and carcinoma case studies
- Biochemical effects in animals
- Traumatic Brain Injury and Neurovascular Disturbances
- Ultrasound and Hyperthermia Applications
- Pickering emulsions and particle stabilization
- MRI in cancer diagnosis
- Mechanisms of cancer metastasis
- Microfluidic and Bio-sensing Technologies
- Atomic and Subatomic Physics Research
University of California, San Francisco
2021-2024
University of California, Berkeley
2021-2022
University of Michigan
2016-2021
Berkeley College
2021
Oxford University Press (United Kingdom)
2020
This study's purpose was to improve understanding of the forces driving complex mechanical interaction between embolic material and current stroke thrombectomy devices by analyzing histological composition strength emboli retrieved from patients evaluating necessary for retrieval such in a middle cerebral artery (MCA) bifurcation model.
This study aimed to develop and demonstrate the in vivo feasibility of a 3D stack-of-spiral balanced steady-state free precession(3D-bSSFP) urea sequence, interleaved with metabolite-specific gradient echo (GRE) sequence for pyruvate metabolic products, improving SNR spatial resolution first hyperpolarized 13 C-MRI human injection co-hyperpolarized [1-13 C]pyruvate [13 C,15 N2 ]urea.A bSSFP imaging was designed using urea-specific excitation pulse, optimized TR, readouts. Simulations phantom...
The development of new endovascular technologies and techniques for mechanical thrombectomy in stroke has greatly relied on benchtop simulators. This paper presents an affordable, versatile, realistic simulation model stroke.
Various micro-engineered tools or platforms have been developed recently for cell mechanics studies based on acoustic, magnetic, and optical actuations. Compared with other techniques single manipulations, microfluidics has the advantages simple working principles device implementations. In this work, we develop a multi-layer microfluidic pipette aspiration integrated pneumatically actuated control valves. This configuration enables decoupling of trapping aspiration, hence causes less...
<h3>BACKGROUND AND PURPOSE:</h3> Aspiration thrombectomy has become a preferred approach to recanalize large-vessel occlusion in stroke with growing trend toward using larger-bore catheters and stronger vacuum pumps. However, the mechanical response of delicate cerebral arteries aspiration force not been evaluated. Here, we provide preclinical clinical evidence intracranial arterial collapse thrombectomy. <h3>MATERIALS METHODS:</h3> We presented case previously implanted flow diverters. then...
Despite advancement of thrombectomy technologies for large-vessel occlusion (LVO) stroke and increased user experience, complete recanalization rates linger around 50%, one-third patients who have undergone successful still experience poor neurological outcomes. To enhance the understanding biomechanics failure modes, authors conducted an experimental analysis interaction emboli/artery/devices in first human brain test platform LVO described to date.In 12 fresh brains, 105 LVOs were...
Endovascular removal of emboli causing large vessel occlusion (LVO)-related stroke utilizing suction catheter and/or stent retriever technologies or thrombectomy is a new standard care. Despite high recanalization rates, 40% patients still experience poor neurological outcomes as many cases cannot be fully reopened after the first attempt. The development endovascular and techniques for mechanical requires more sophisticated testing platforms that overcome limitations phantom-based...
Purpose To develop techniques and establish a workflow using hyperpolarized carbon‐13 ( 13 C) MRI the pyruvate‐to‐lactate conversion rate (k PL ) biomarker to guide MR‐transrectal ultrasound fusion prostate biopsies. Methods The integrated multiparametric (mpMRI) exam consisted of 1‐min C‐pyruvate EPI acquisition added conventional mpMRI exam. Maps k values were calculated, uploaded picture archiving communication system targeting platform, displayed as color overlays on T 2 ‐weighted...
e15059 Background: Hyperpolarized 13 C (HP C) MRI is a novel molecular imaging approach that detects aberrant aerobic metabolism, namely elevated rates of pyruvate-to-lactate conversion (k PL ), in patients with advanced malignancies. Higher k has been shown to correlate higher tumor grade among localized prostate cancer (PC). This research sought evaluate the correlation between and clinical outcome measures PC. Methods: Patients metastatic or locally PC (castration sensitive resistant)...
[13C,15N2]urea and [1-13C]pyruvate were polarized together using dynamic nuclear polarization simultaneously injected into healthy volunteers for simultaneous imaging of metabolism perfusion in the abdomen. Whole-abdomen images successfully obtained distribution urea was compared to pyruvate its metabolites. While relative intensity various organs similar between pyruvate, temporal courses different. This represents first use co-polarized human abdomen, will be a powerful potential tool...
The first-in-human hyperpolarized [1-13C]pyruvate+[13C,15N2]urea dual-agent MRI demonstrated the safety and feasibility of simultaneous characterization prostate cancer metabolism blood flow as a two-minute addition to standard 1H-multiparametric MRI. Metabolism-perfusion mismatch (i.e. elevated pyruvate-lactate conversion decreased urea perfusion) in subregions high-grade tumor was agreement with histopathological immunochemical markers that reflected lethal phenotypes their associated...
Motivation: To address the issues with original dual-element 13C/1H endorectal coil (ERC). Goal(s): We designed and fabricated a novel ERC, validated bench testing then evaluated in 3T MRI studies. Approach: Phantoms were imaged using new ERC ERC. Acquired data was analyzed respective SNR compared. Results: The demonstrated substantially improved 13C 1H sensitivity on electronic testing. In addition, substantial improvement signal-to-noise ratio, since has successfully been used...
Motivation: Monitoring the progression or response of advanced prostate metastases is a current clinical unmet need that not reliably delineated with CT and PET. Goal(s): Here, we developed high-resolution whole abdominopelvic [1-13C]pyruvate HP MRI approach for metabolic biomarker characterization in cancer patients. Approach: A variable-resolution imaging was used to provide [1-13C]pyruvate, robust spatiotemporal denoising B1+ variation correction methods were quantify rate-constant...
Motivation: Hyperpolarized (HP) 13C-pyruvate MRI can address limitations of PSMA-PET for monitoring therapy and evaluating treatment-emergent, lethal subtypes prostate cancer. Goal(s): To establish characterize a novel radiomics framework tumor metabolism in advanced cancer based on whole abdominopelvic HP MRI. Approach: We extracted 316 metabolic features from 16 patients. Following feature selection classification, their prognostic values were evaluated using uni- multivariate survival...
Serial hyperpolarized 13 C+mpMRI and paired metabolic image-guided biopsy were employed in a new integrative active surveillance (AS) paradigm, exemplified by patient who initially enrolled AS for 5 years, but later underwent radical prostatectomy upon progression. Metabolic biomarker k PL images detected early progression preceding radiologic clinical parameters. Final whole-gland histopathology also linked PI-RADS targets to multifocal tumors, where spatially reflected intratumoral...
<h3>Introduction</h3> Cerebrovascular test beds for large vessel occlusion (LVO) stroke are widely used to evaluate and develop new thrombectomy technologies strategies. Most of the studies on described fabrication cerebrovascular phantoms but not flow circuit clot analogs, which essential components replicate LVO in patients with stroke. In addition, made from different materials techniques may result biased testing results. However, such comparison has been studied. We describe detail...
<h3>Introduction</h3> Cerebral artery phantoms are valuable tools to test recanalization strategies of large vessel occlusion (LVO). However, these artificial models do not mimic the complex angioarchitecture and hemodynamic conditions human cerebrovasculature, embolus/endothelium interaction, nor response delicate arterial walls mechanical forces. In-vivo animal also available; however, such represent geometry, structure, or cerebral arteries. To overcome inadequacies, we present a bed...
<h3>Introduction</h3> Mechanical thrombectomy using a suction catheter, stent or the combination of both has recently become standard care for large vessel occlusion (LVO) stroke. However, complete recanalization (mTICI=3) with best neurological outcome can be achieved in only 50% cases. In addition, multiple devices and passes are usually needed to recanalize, prolonging procedure times, increasing risks damage. To improve our understanding interaction between embolus devices, this study we...
Savastano, Luis E MD; Liu, Yang; Gebrezgiabhier, Daniel; Reddy, Adithya; Davis, Evan; Zheng, Yihao; Shih, Albert; Pandey, Aditya S MD Author Information
Introduction: Suction catheters and stent retrievers are based on the classical paradigm of “en bloc” removal emboli by generation tensile forces vacuum or device withdrawal. However, in this process elongate fracture leading to fragmentation. Fragments can migrate downstream remain impacted arterial wall resulting a residual occlusion. Hypothesis: Clot ingestion is biomechanically superior leads higher recanalization rates with less complications. Methods: To test hypothesis, we present...
<h3>Introduction</h3> Complete recanalization in large vessel occlusion (LVO) strokes with suction catheters and stent retrievers has remained at 50% despite improved technologies accumulating operator experience. About 40% of patients experience poor neurological outcomes many cannot be recanalized the first attempt. In this experimental study, we aimed to analyze interaction between arteries/emboli/devices human brains provide mechanistic explanations failures complications current...
<h3>Introduction</h3> New generation aspiration catheters have larger bore size and are equipped with stronger pumps to provide higher force. We analyzed the mechanical response of cerebral arteries under thrombectomy in preclinical models characterized features affecting likelihood severity arterial collapse. <h3>Materials Methods</h3> Fresh whole human brains (n=9) were harvested connected a saline flow system physiologically representative pressure rates. Aspiration (n=168, 54 M1, 52 M2,...