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Ghigo N, Ramos-Palacios G, Bourquin C, Xing P, Wu A, Cortés N, Ladret H, Ikan L, Casanova C, Porée J, Sadikot A, Provost J. Dynamic Ultrasound Localization Microscopy Without ECG-Gating. ULTRASOUND IN MEDICINE & BIOLOGY 2024; 50:1436-1448. [PMID: 38969526 DOI: 10.1016/j.ultrasmedbio.2024.05.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 05/04/2024] [Accepted: 05/22/2024] [Indexed: 07/07/2024]
Abstract
OBJECTIVE Dynamic Ultrasound Localization Microscopy (DULM) has first been developed for non-invasive Pulsatility measurements in the rodent brain. DULM relies on the localization and tracking of microbubbles (MBs) injected into the bloodstream, to obtain highly resolved velocity and density cine-loops. Previous DULM techniques required ECG-gating, limiting its application to specific datasets, and increasing acquisition time. The objective of this study is to eliminate the need for ECG-gating in DULM experiments by introducing a motion-matching method for time registration. METHODS We developed a motion-matching algorithm based on tissue Doppler that leverages the cyclic tissue motion within the brain. Tissue Doppler was estimated for each group of frames in the acquisitions, at multiple locations identified as local maxima in the skin above the skull. Subsequently, each group of frames was time-registered to a reference group by delaying it based on the maximum correlation value between their respective tissue Doppler signals. This synchronization ensured that each group of frames aligned with the brain tissue motion of the reference group, and consequently, with its cardiac cycle. As a result, velocities of MBs could be averaged to retrieve flow velocity variations over time. RESULTS Initially validated in ECG-gated acquisitions in a rat model (n = 1), the proposed method was successfully applied in a mice model in 2D (n = 3) and in a feline model in 3D (n = 1). Performing time-registration with the proposed motion-matching method or by using ECG-gating leads to similar results. For the first time, dynamic velocity and density cine-loops were extracted without the need for any information on the animal ECG, and complex dynamic markers such as the Pulsatility index were estimated. CONCLUSION Results suggest that DULM can be performed without external gating, enabling the use of DULM on any ULM dataset where enough MBs are detectable. Time registration by motion-matching represents a significant advancement in DULM techniques, making DULM more accessible by simplifying its experimental complexity.
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Affiliation(s)
- Nin Ghigo
- Department of Engineering Physics, Polytechnique Montréal, Montréal, Quebec, Canada.
| | | | - Chloé Bourquin
- Department of Engineering Physics, Polytechnique Montréal, Montréal, Quebec, Canada
| | - Paul Xing
- Department of Engineering Physics, Polytechnique Montréal, Montréal, Quebec, Canada
| | - Alice Wu
- Department of Engineering Physics, Polytechnique Montréal, Montréal, Quebec, Canada
| | - Nelson Cortés
- School of Optometry, University of Montreal, Montréal, Quebec, Canada
| | - Hugo Ladret
- School of Optometry, University of Montreal, Montréal, Quebec, Canada; Institut de Neurosciences de la Timone, UMR 7289, CNRS and Aix-Marseille Université, Marseille, France
| | - Lamyae Ikan
- School of Optometry, University of Montreal, Montréal, Quebec, Canada
| | | | - Jonathan Porée
- Department of Engineering Physics, Polytechnique Montréal, Montréal, Quebec, Canada
| | - Abbas Sadikot
- Montreal Neurological Institute, McGill University, Montréal, Quebec, Canada
| | - Jean Provost
- Department of Engineering Physics, Polytechnique Montréal, Montréal, Quebec, Canada; Montreal Heart Institute, Montréal, Quebec, Canada
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2
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Yan J, Huang B, Tonko J, Toulemonde M, Hansen-Shearer J, Tan Q, Riemer K, Ntagiantas K, Chowdhury RA, Lambiase PD, Senior R, Tang MX. Transthoracic ultrasound localization microscopy of myocardial vasculature in patients. Nat Biomed Eng 2024; 8:689-700. [PMID: 38710839 PMCID: PMC11250254 DOI: 10.1038/s41551-024-01206-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Accepted: 03/30/2024] [Indexed: 05/08/2024]
Abstract
Myocardial microvasculature and haemodynamics are indicative of potential microvascular diseases for patients with symptoms of coronary heart disease in the absence of obstructive coronary arteries. However, imaging microvascular structure and flow within the myocardium is challenging owing to the small size of the vessels and the constant movement of the patient's heart. Here we show the feasibility of transthoracic ultrasound localization microscopy for imaging myocardial microvasculature and haemodynamics in explanted pig hearts and in patients in vivo. Through a customized data-acquisition and processing pipeline with a cardiac phased-array probe, we leveraged motion correction and tracking to reconstruct the dynamics of microcirculation. For four patients, two of whom had impaired myocardial function, we obtained super-resolution images of myocardial vascular structure and flow using data acquired within a breath hold. Myocardial ultrasound localization microscopy may facilitate the understanding of myocardial microcirculation and the management of patients with cardiac microvascular diseases.
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Affiliation(s)
- Jipeng Yan
- Ultrasound Lab for Imaging and Sensing, Department of Bioengineering, Imperial College London, London, UK
| | - Biao Huang
- Ultrasound Lab for Imaging and Sensing, Department of Bioengineering, Imperial College London, London, UK
| | - Johanna Tonko
- Institute of Cardiovascular Science, University College London, London, UK
| | - Matthieu Toulemonde
- Ultrasound Lab for Imaging and Sensing, Department of Bioengineering, Imperial College London, London, UK
| | - Joseph Hansen-Shearer
- Ultrasound Lab for Imaging and Sensing, Department of Bioengineering, Imperial College London, London, UK
| | - Qingyuan Tan
- Ultrasound Lab for Imaging and Sensing, Department of Bioengineering, Imperial College London, London, UK
| | - Kai Riemer
- Ultrasound Lab for Imaging and Sensing, Department of Bioengineering, Imperial College London, London, UK
| | | | - Rasheda A Chowdhury
- Faculty of Medicine, National Heart and Lung Institute, Imperial College London, London, UK
| | - Pier D Lambiase
- Institute of Cardiovascular Science, University College London, London, UK
| | - Roxy Senior
- Faculty of Medicine, National Heart and Lung Institute, Imperial College London, London, UK
- Royal Brompton Hospital, London, UK
- Northwick Park Hospital, Harrow, UK
| | - Meng-Xing Tang
- Ultrasound Lab for Imaging and Sensing, Department of Bioengineering, Imperial College London, London, UK.
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Shin Y, Lowerison MR, Wang Y, Chen X, You Q, Dong Z, Anastasio MA, Song P. Context-aware deep learning enables high-efficacy localization of high concentration microbubbles for super-resolution ultrasound localization microscopy. Nat Commun 2024; 15:2932. [PMID: 38575577 PMCID: PMC10995206 DOI: 10.1038/s41467-024-47154-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Accepted: 03/20/2024] [Indexed: 04/06/2024] Open
Abstract
Ultrasound localization microscopy (ULM) enables deep tissue microvascular imaging by localizing and tracking intravenously injected microbubbles circulating in the bloodstream. However, conventional localization techniques require spatially isolated microbubbles, resulting in prolonged imaging time to obtain detailed microvascular maps. Here, we introduce LOcalization with Context Awareness (LOCA)-ULM, a deep learning-based microbubble simulation and localization pipeline designed to enhance localization performance in high microbubble concentrations. In silico, LOCA-ULM enhanced microbubble detection accuracy to 97.8% and reduced the missing rate to 23.8%, outperforming conventional and deep learning-based localization methods up to 17.4% in accuracy and 37.6% in missing rate reduction. In in vivo rat brain imaging, LOCA-ULM revealed dense cerebrovascular networks and spatially adjacent microvessels undetected by conventional ULM. We further demonstrate the superior localization performance of LOCA-ULM in functional ULM (fULM) where LOCA-ULM significantly increased the functional imaging sensitivity of fULM to hemodynamic responses invoked by whisker stimulations in the rat brain.
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Affiliation(s)
- YiRang Shin
- Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, IL, USA
- Department of Electrical and Computer Engineering, University of Illinois Urbana-Champaign, Urbana, IL, USA
| | - Matthew R Lowerison
- Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, IL, USA
- Department of Electrical and Computer Engineering, University of Illinois Urbana-Champaign, Urbana, IL, USA
| | - Yike Wang
- Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, IL, USA
- Department of Electrical and Computer Engineering, University of Illinois Urbana-Champaign, Urbana, IL, USA
| | - Xi Chen
- Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, IL, USA
- Department of Electrical and Computer Engineering, University of Illinois Urbana-Champaign, Urbana, IL, USA
| | - Qi You
- Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, IL, USA
- Department of Bioengineering, University of Illinois Urbana-Champaign, Urbana, IL, USA
| | - Zhijie Dong
- Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, IL, USA
- Department of Electrical and Computer Engineering, University of Illinois Urbana-Champaign, Urbana, IL, USA
| | - Mark A Anastasio
- Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, IL, USA
- Department of Electrical and Computer Engineering, University of Illinois Urbana-Champaign, Urbana, IL, USA
- Department of Bioengineering, University of Illinois Urbana-Champaign, Urbana, IL, USA
- Carle Illinois College of Medicine, University of Illinois Urbana-Champaign, Urbana, IL, USA
| | - Pengfei Song
- Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, IL, USA.
- Department of Electrical and Computer Engineering, University of Illinois Urbana-Champaign, Urbana, IL, USA.
- Department of Bioengineering, University of Illinois Urbana-Champaign, Urbana, IL, USA.
- Carle Illinois College of Medicine, University of Illinois Urbana-Champaign, Urbana, IL, USA.
- Neuroscience Program, University of Illinois Urbana-Champaign, Urbana, IL, USA.
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Jin T, Li B, Li L, Qi W, Xi L. High spatiotemporal mapping of cortical blood flow velocity with an enhanced accuracy. BIOMEDICAL OPTICS EXPRESS 2024; 15:2419-2432. [PMID: 38633086 PMCID: PMC11019678 DOI: 10.1364/boe.520886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 03/04/2024] [Accepted: 03/04/2024] [Indexed: 04/19/2024]
Abstract
Cerebral blood flow velocity is one of the most essential parameters related to brain functions and diseases. However, most existing mapping methods suffer from either inaccuracy or lengthy sampling time. In this study, we propose a particle-size-related calibration method to improve the measurement accuracy and a random-access strategy to suppress the sampling time. Based on the proposed methods, we study the long-term progress of cortical vasculopathy and abnormal blood flow caused by glioma, short-term variations of blood flow velocity under different anesthetic depths, and cortex-wide connectivity of the rapid fluctuation of blood flow velocities during seizure onset. The experimental results demonstrate that the proposed calibration method and the random-access strategy can improve both the qualitative and quantitative performance of velocimetry techniques and are also beneficial for understanding brain functions and diseases from the perspective of cerebral blood flow.
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Affiliation(s)
- Tian Jin
- Department of Biomedical Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
| | - Baochen Li
- Department of Biomedical Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
| | - Linyang Li
- Department of Biomedical Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
| | - Weizhi Qi
- Department of Biomedical Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
| | - Lei Xi
- Department of Biomedical Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
- Guangdong Provincial Key Laboratory of Advanced Biomaterials, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
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5
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Bourquin C, Porée J, Rauby B, Perrot V, Ghigo N, Belgharbi H, Bélanger S, Ramos-Palacios G, Cortes N, Ladret H, Ikan L, Casanova C, Lesage F, Provost J. Quantitative pulsatility measurements using 3D dynamic ultrasound localization microscopy. Phys Med Biol 2024; 69:045017. [PMID: 38181421 DOI: 10.1088/1361-6560/ad1b68] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 01/05/2024] [Indexed: 01/07/2024]
Abstract
A rise in blood flow velocity variations (i.e. pulsatility) in the brain, caused by the stiffening of upstream arteries, is associated with cognitive impairment and neurodegenerative diseases. The study of this phenomenon requires brain-wide pulsatility measurements, with large penetration depth and high spatiotemporal resolution. The development of dynamic ultrasound localization microscopy (DULM), based on ULM, has enabled pulsatility measurements in the rodent brain in 2D. However, 2D imaging accesses only one slice of the brain and measures only 2D-projected and hence biased velocities . Herein, we present 3D DULM: using a single ultrasound scanner at high frame rate (1000-2000 Hz), this method can produce dynamic maps of microbubbles flowing in the bloodstream and extract quantitative pulsatility measurements in the cat brain with craniotomy and in the mouse brain through the skull, showing a wide range of flow hemodynamics in both large and small vessels. We highlighted a decrease in pulsatility along the vascular tree in the cat brain, which could be mapped with ultrasound down to a few tens of micrometers for the first time. We also performed an intra-animal validation of the method by showing consistent measurements between the two sides of the Willis circle in the mouse brain. Our study provides the first step towards a new biomarker that would allow the detection of dynamic abnormalities in microvessels in the brain, which could be linked to early signs of neurodegenerative diseases.
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Affiliation(s)
- Chloé Bourquin
- Department of Engineering Physics, Polytechnique Montréal, Montréal, QC H3T 1J4, Canada
| | - Jonathan Porée
- Department of Engineering Physics, Polytechnique Montréal, Montréal, QC H3T 1J4, Canada
| | - Brice Rauby
- Department of Engineering Physics, Polytechnique Montréal, Montréal, QC H3T 1J4, Canada
| | - Vincent Perrot
- Department of Engineering Physics, Polytechnique Montréal, Montréal, QC H3T 1J4, Canada
| | - Nin Ghigo
- Department of Engineering Physics, Polytechnique Montréal, Montréal, QC H3T 1J4, Canada
| | - Hatim Belgharbi
- Department of Engineering Physics, Polytechnique Montréal, Montréal, QC H3T 1J4, Canada
- Department of Biomedical Engineering, University of North Carolina, Chapel Hill, NC 27599, United States of America
| | | | | | - Nelson Cortes
- School of Optometry, University of Montreal, Montréal, QC H3T 1P1, Canada
| | - Hugo Ladret
- School of Optometry, University of Montreal, Montréal, QC H3T 1P1, Canada
- Institut de Neurosciences de la Timone, UMR 7289, CNRS and Aix-Marseille Université, Marseille, F-13005, France
| | - Lamyae Ikan
- School of Optometry, University of Montreal, Montréal, QC H3T 1P1, Canada
| | - Christian Casanova
- School of Optometry, University of Montreal, Montréal, QC H3T 1P1, Canada
| | - Frédéric Lesage
- Department of Electrical Engineering, Polytechnique Montréal, Montréal, QC H3T 1J4, Canada
- Montreal Heart Institute, Montréal, QC H1T 1C8, Canada
| | - Jean Provost
- Department of Engineering Physics, Polytechnique Montréal, Montréal, QC H3T 1J4, Canada
- Montreal Heart Institute, Montréal, QC H1T 1C8, Canada
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6
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Yan J, Wang B, Riemer K, Hansen-Shearer J, Lerendegui M, Toulemonde M, Rowlands CJ, Weinberg PD, Tang MX. Fast 3D Super-Resolution Ultrasound With Adaptive Weight-Based Beamforming. IEEE Trans Biomed Eng 2023; 70:2752-2761. [PMID: 37015124 PMCID: PMC7614997 DOI: 10.1109/tbme.2023.3263369] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/01/2023]
Abstract
OBJECTIVE Super-resolution ultrasound (SRUS) imaging through localising and tracking sparse microbubbles has been shown to reveal microvascular structure and flow beyond the wave diffraction limit. Most SRUS studies use standard delay and sum (DAS) beamforming, where high side lobes and broad main lobes make isolation and localisation of densely distributed bubbles challenging, particularly in 3D due to the typically small aperture of matrix array probes. METHOD This study aimed to improve 3D SRUS by implementing a new fast 3D coherence beamformer based on channel signal variance. Two additional fast coherence beamformers, that have been implemented in 2D were implemented in 3D for the first time as comparison: a nonlinear beamformer with p-th root compression and a coherence factor beamformer. The 3D coherence beamformers, together with DAS, were compared in computer simulation, on a microflow phantom and in vivo. RESULTS Simulation results demonstrated that all three adaptive weight-based beamformers can narrow the main lobe, suppress the side lobes, while maintaining the weaker scatter signals. Improved 3D SRUS images of microflow phantom and a rabbit kidney within a 3-second acquisition were obtained using the adaptive weight-based beamformers, when compared with DAS. CONCLUSION The adaptive weight-based 3D beamformers can improve the SRUS and the proposed variance-based beamformer performs best in simulations and experiments. SIGNIFICANCE Fast 3D SRUS would significantly enhance the potential utility of this emerging imaging modality in a broad range of biomedical applications.
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Affiliation(s)
- Jipeng Yan
- Ultrasound Lab for Imaging and Sensing, Department of Bioengineering, Imperial College London, London, UK, SW7 2AZ
| | - Bingxue Wang
- Ultrasound Lab for Imaging and Sensing, Department of Bioengineering, Imperial College London, London, UK, SW7 2AZ
| | - Kai Riemer
- Ultrasound Lab for Imaging and Sensing, Department of Bioengineering, Imperial College London, London, UK, SW7 2AZ
| | - Joseph Hansen-Shearer
- Ultrasound Lab for Imaging and Sensing, Department of Bioengineering, Imperial College London, London, UK, SW7 2AZ
| | - Marcelo Lerendegui
- Ultrasound Lab for Imaging and Sensing, Department of Bioengineering, Imperial College London, London, UK, SW7 2AZ
| | - Matthieu Toulemonde
- Ultrasound Lab for Imaging and Sensing, Department of Bioengineering, Imperial College London, London, UK, SW7 2AZ
| | | | - Peter D. Weinberg
- Department of Bioengineering, Imperial College London, London, UK, SW7 2AZ
| | - Meng-Xing Tang
- Ultrasound Lab for Imaging and Sensing, Department of Bioengineering, Imperial College London, London, UK, SW7 2AZ
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7
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Song P, Rubin JM, Lowerison MR. Super-resolution ultrasound microvascular imaging: Is it ready for clinical use? Z Med Phys 2023; 33:309-323. [PMID: 37211457 PMCID: PMC10517403 DOI: 10.1016/j.zemedi.2023.04.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 03/31/2023] [Accepted: 04/01/2023] [Indexed: 05/23/2023]
Abstract
The field of super-resolution ultrasound microvascular imaging has been rapidly growing over the past decade. By leveraging contrast microbubbles as point targets for localization and tracking, super-resolution ultrasound pinpoints the location of microvessels and measures their blood flow velocity. Super-resolution ultrasound is the first in vivo imaging modality that can image micron-scale vessels at a clinically relevant imaging depth without tissue destruction. These unique capabilities of super-resolution ultrasound provide structural (vessel morphology) and functional (vessel blood flow) assessments of tissue microvasculature on a global and local scale, which opens new doors for many enticing preclinical and clinical applications that benefit from microvascular biomarkers. The goal of this short review is to provide an update on recent advancements in super-resolution ultrasound imaging, with a focus on summarizing existing applications and discussing the prospects of translating super-resolution imaging to clinical practice and research. In this review, we also provide brief introductions of how super-resolution ultrasound works, how does it compare with other imaging modalities, and what are the tradeoffs and limitations for an audience who is not familiar with the technology.
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Affiliation(s)
- Pengfei Song
- Department of Electrical and Computer Engineering, University of Illinois Urbana-Champaign, United States; Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, United States; Department of Bioengineering, University of Illinois Urbana-Champaign, United States; Carle Illinois College of Medicine, University of Illinois Urbana-Champaign, United States.
| | - Jonathan M Rubin
- Department of Radiology, University of Michigan, Ann Arbor, United States
| | - Matthew R Lowerison
- Department of Electrical and Computer Engineering, University of Illinois Urbana-Champaign, United States; Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, United States
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8
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Guo X, Ta D, Xu K. Frame rate effects and their compensation on super-resolution microvessel imaging using ultrasound localization microscopy. ULTRASONICS 2023; 132:107009. [PMID: 37060620 DOI: 10.1016/j.ultras.2023.107009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 03/21/2023] [Accepted: 04/07/2023] [Indexed: 05/29/2023]
Abstract
Ultrasound localization microscopy (ULM) breaks the diffraction limit and allows imaging microvasculature at micrometric resolution while preserving the penetration depth. Frame rate plays an important role for high-quality ULM imaging, but there is still a lack of review and investigation of the frame rate effects on ULM. This work aims to clarify how frame rate influences the performance of ULM, including the effects of microbubble detection, localization and tracking. The performance of ULM was evaluated using an in vivo rat brain dataset (15.6 MHz, 3 tilted plane waves (-5°, 0°, +5°), at a compounded frame rate of 1000 Hz) with different frame rates. Quantification methods, including Fourier ring correlation and saturation parameter, were applied to analyze the spatial resolution and reconstruction efficiency, respectively. In addition, effects on each crucial step in ULM processing were further analyzed. Results showed that when frame rates dropped from 1000 Hz to 250 Hz, the spatial resolution deteriorated from 9.9 μm to 15.0 μm. Applying a velocity constraint was able to improve the ULM performance, but inappropriate constraint may artificially result in high apparent resolution. For the dataset, compared with the results of 1000 Hz frame rate, the velocity was underestimated at 100 Hz with 47.18% difference and the saturation was reduced from 55.00% at 1000 Hz to 43.34% at 100 Hz. Analysis showed that inadequate frame rate generated unreliable microbubble detection, localization and tracking as well as incomplete track reconstruction, resulting in the deterioration in spatial resolution, the underestimation in velocity measurement and the decrease in saturation. Finally, a guidance of determining the frame rate requirement was discussed by considering the required spatial sampling points based on vessel morphology, clutter filtering method, tracking algorithm and acquisition time, which provides indications for future clinical application of ULM method.
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Affiliation(s)
- Xingyi Guo
- Center for Biomedical Engineering, School of Information Science and Technology, Fudan University, Shanghai 200438, China; State Key Laboratory of Integrated Chips and Systems, Fudan University, Shanghai 201203, China
| | - Dean Ta
- Center for Biomedical Engineering, School of Information Science and Technology, Fudan University, Shanghai 200438, China; State Key Laboratory of Integrated Chips and Systems, Fudan University, Shanghai 201203, China; Yiwu Research Institute of Fudan University, Zhejiang 322000, China
| | - Kailiang Xu
- Center for Biomedical Engineering, School of Information Science and Technology, Fudan University, Shanghai 200438, China; State Key Laboratory of Integrated Chips and Systems, Fudan University, Shanghai 201203, China; Yiwu Research Institute of Fudan University, Zhejiang 322000, China.
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9
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Andersen SB, Sørensen CM, Jensen JA, Nielsen MB. Microvascular Imaging with Super-Resolution Ultrasound. ULTRASCHALL IN DER MEDIZIN (STUTTGART, GERMANY : 1980) 2022; 43:543-547. [PMID: 36470255 DOI: 10.1055/a-1937-6868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
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10
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Functional ultrasound localization microscopy reveals brain-wide neurovascular activity on a microscopic scale. Nat Methods 2022; 19:1004-1012. [PMID: 35927475 PMCID: PMC9352591 DOI: 10.1038/s41592-022-01549-5] [Citation(s) in RCA: 36] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Accepted: 06/14/2022] [Indexed: 12/02/2022]
Abstract
The advent of neuroimaging has increased our understanding of brain function. While most brain-wide functional imaging modalities exploit neurovascular coupling to map brain activity at millimeter resolutions, the recording of functional responses at microscopic scale in mammals remains the privilege of invasive electrophysiological or optical approaches, but is mostly restricted to either the cortical surface or the vicinity of implanted sensors. Ultrasound localization microscopy (ULM) has achieved transcranial imaging of cerebrovascular flow, up to micrometre scales, by localizing intravenously injected microbubbles; however, the long acquisition time required to detect microbubbles within microscopic vessels has so far restricted ULM application mainly to microvasculature structural imaging. Here we show how ULM can be modified to quantify functional hyperemia dynamically during brain activation reaching a 6.5-µm spatial and 1-s temporal resolution in deep regions of the rat brain. Functional ultrasound localization microscopy monitors cerebrovascular blood flow by detecting the flow of injected microbubbles, providing access to brain activity at high spatiotemporal resolution.
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Super-Resolution Ultrasound Imaging Can Quantify Alterations in Microbubble Velocities in the Renal Vasculature of Rats. Diagnostics (Basel) 2022; 12:diagnostics12051111. [PMID: 35626267 PMCID: PMC9140053 DOI: 10.3390/diagnostics12051111] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 04/04/2022] [Accepted: 04/27/2022] [Indexed: 11/17/2022] Open
Abstract
Super-resolution ultrasound imaging, based on the localization and tracking of single intravascular microbubbles, makes it possible to map vessels below 100 µm. Microbubble velocities can be estimated as a surrogate for blood velocity, but their clinical potential is unclear. We investigated if a decrease in microbubble velocity in the arterial and venous beds of the renal cortex, outer medulla, and inner medulla was detectable after intravenous administration of the α1-adrenoceptor antagonist prazosin. The left kidneys of seven rats were scanned with super-resolution ultrasound for 10 min before, during, and after prazosin administration using a bk5000 ultrasound scanner and hockey-stick probe. The super-resolution images were manually segmented, separating cortex, outer medulla, and inner medulla. Microbubble tracks from arteries/arterioles were separated from vein/venule tracks using the arterial blood flow direction. The mean microbubble velocities from each scan were compared. This showed a significant prazosin-induced velocity decrease only in the cortical arteries/arterioles (from 1.59 ± 0.38 to 1.14 ± 0.31 to 1.18 ± 0.33 mm/s, p = 0.013) and outer medulla descending vasa recta (from 0.70 ± 0.05 to 0.66 ± 0.04 to 0.69 ± 0.06 mm/s, p = 0.026). Conclusively, super-resolution ultrasound imaging makes it possible to detect and differentiate microbubble velocity responses to prazosin simultaneously in the renal cortical and medullary vascular beds.
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12
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Qiu L, Zhang J, Yang Y, Zhang H, Lee FF, He Q, Huang C, Huang L, Qian L, Luo J. In Vivo assessment of hypertensive nephrosclerosis using ultrasound localization microscopy. Med Phys 2022; 49:2295-2308. [PMID: 35218672 DOI: 10.1002/mp.15583] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 01/27/2022] [Accepted: 02/21/2022] [Indexed: 11/07/2022] Open
Abstract
PURPOSE As a typical chronic kidney disease (CKD), hypertensive nephrosclerosis (HN) is a common syndrome of hypertension, characterized by chronic kidney microvascular damage. Early diagnosis of microvascular damage using conventional ultrasound imaging encounters challenges in sensitivity and specificity owing to the inherent diffraction limit. Ultrasound localization microscopy (ULM) has been developed to obtain microvasculature and microvascular hemodynamics within the kidney, and would be a promising tool for early diagnosis of CKD. METHODS In this study, the advantage of quantitative indexes obtained by using ULM (mean arterial blood flow speeds of different segments of interlobular arteries) over indexes obtained using conventional clinical serum (β2-microglobulin, serum urea nitrogen and creatinine) and urine (24-hour urine volume and urine protein) tests and ultrasound Doppler imaging [peak systolic velocity (PSV), end-diastolic velocity (EDV) and resistance index (RI)] and contrast-enhanced ultrasound imaging [CEUS; rise time (RT), peak intensity (IMAX), mean transit time (mTT) and area under the time-intensity curve (AUC)] for early diagnosis of HN was investigated. Examinations were carried out on 6 spontaneously hypertensive rats (SHR) and 5 normal Wistar-Kyoto (WKY) rats at the age of 10 weeks. RESULTS The experimental results showed that the indicators derived from conventional clinical inspections (serum and urine tests) and ultrasound imaging (PSV, EDV, RI, RT, IMAX, mTT and AUC) did not show significant difference between hypertensive and healthy rats (p > 0.05), while the TTP of the SHR group (28.52 ± 5.52 s) derived from CEUS is significantly higher than that of the WKY group (18.68 ± 7.32 s; p < 0.05). The mean blood flow speed in interlobular artery of SHR (12.47 ± 1.06 mm/s) derived from ULM is significantly higher than that of WKY rats (10.13 ± 1.17 mm/s; p < 0.01). CONCLUSION The advantages of ULM over conventional clinical inspections and ultrasound imaging methods for early diagnosis of HN were validated. The quantitative results showed that ULM can effectively diagnose HN at the early stage by detecting the blood flow speed changes of interlobular arteries. ULM may promise a reliable technique for early diagnosis of HN in the future. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Lanyan Qiu
- Department of Ultrasound, Beijing Friendship Hospital, Capital Medical University, Beijing, 100050, China
| | - Jingke Zhang
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, 100084, China
| | - Yi Yang
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, 100084, China
| | - Hong Zhang
- Department of Ultrasound, Beijing Friendship Hospital, Capital Medical University, Beijing, 100050, China
| | - Fu-Feng Lee
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, 100084, China
| | - Qiong He
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, 100084, China.,Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Chengwu Huang
- Department of Radiology, Mayo Clinic College of Medicine and Science, Rochester, MN, 55905, USA
| | - Lijie Huang
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, 100084, China
| | - Linxue Qian
- Department of Ultrasound, Beijing Friendship Hospital, Capital Medical University, Beijing, 100050, China
| | - Jianwen Luo
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, 100084, China
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