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Anastasiadis P, Mohammadabadi A, Fishman MJ, Smith JA, Nguyen BA, Hersh DS, Frenkel V. Design, characterization and evaluation of a laser-guided focused ultrasound system for preclinical investigations. Biomed Eng Online 2019; 18:36. [PMID: 30922312 PMCID: PMC6440155 DOI: 10.1186/s12938-019-0656-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Accepted: 03/19/2019] [Indexed: 01/29/2023] Open
Abstract
Background The clinical applications of transcranial focused ultrasound continue to expand and include ablation as well as drug delivery applications in the brain, where treatments are typically guided by MRI. Although MRI-guided focused ultrasound systems are also preferred for many preclinical investigations, they are expensive to purchase and operate, and require the presence of a nearby imaging center. For many basic mechanistic studies, however, MRI is not required. The purpose of this study was to design, construct, characterize and evaluate a portable, custom, laser-guided focused ultrasound system for noninvasive, transcranial treatments in small rodents. Methods The system comprised an off-the-shelf focused ultrasound transducer and amplifier, with a custom cone fabricated for direct coupling of the transducer to the head region. A laser-guidance apparatus was constructed with a 3D stage for accurate positioning to 1 mm. Pressure field simulations were performed to demonstrate the effects of the coupling cone and the sealing membrane, as well as for determining the location of the focus and acoustic transmission across rat skulls over a range of sizes. Hydrophone measurements and exposures in hydrogels were used to assess the accuracy of the simulations. In vivo treatments were performed in rodents for opening the blood–brain barrier and to assess the performance and accuracy of the system. The effects of varying the acoustic pressure, microbubble dose and animal size were evaluated in terms of efficacy and safety of the treatments. Results The simulation results were validated by the hydrophone measurements and exposures in the hydrogels. The in vivo treatments demonstrated the ability of the system to open the blood–brain barrier. A higher acoustic pressure was required in larger-sized animals, as predicted by the simulations and transmission measurements. In a particular sized animal, the degree of blood–brain barrier opening, and the safety of the treatments were directly associated with the microbubble dose. Conclusion The focused ultrasound system that was developed was found to be a cost-effective alternative to MRI-guided systems as an investigational device that is capable of accurately providing noninvasive, transcranial treatments in rodents.
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Affiliation(s)
- Pavlos Anastasiadis
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, 22 S. Greene St., Baltimore, MD, 21201, USA.,Marlene and Stewart Greenebaum Comprehensive Cancer Center, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Ali Mohammadabadi
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, 22 S. Greene St., Baltimore, MD, 21201, USA
| | - Meyer J Fishman
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, 22 S. Greene St., Baltimore, MD, 21201, USA
| | - Jesse A Smith
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, 22 S. Greene St., Baltimore, MD, 21201, USA
| | - Ben A Nguyen
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, 22 S. Greene St., Baltimore, MD, 21201, USA
| | - David S Hersh
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Victor Frenkel
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, 22 S. Greene St., Baltimore, MD, 21201, USA. .,Marlene and Stewart Greenebaum Comprehensive Cancer Center, University of Maryland School of Medicine, Baltimore, MD, USA.
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Wei Y, Shang N, Jin H, He Y, Pan Y, Xiao N, Wei J, Xiao S, Chen L, Liu J. Penetration of different molecule sizes upon ultrasound combined with microbubbles in a superficial tumour model. J Drug Target 2019; 27:1068-1075. [PMID: 30892098 DOI: 10.1080/1061186x.2019.1588279] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Yingli Wei
- Department of Ultrasound, Guangdong Women and Children Hospital, Guangzhou, China
| | - Ning Shang
- Department of Ultrasound, Guangdong Women and Children Hospital, Guangzhou, China
| | - Hai Jin
- Department of Medical Ultrasound, Guangzhou First People’s Hospital, Guangzhou, China
| | - Yan He
- Department of Medical Ultrasound, Guangzhou First People’s Hospital, Guangzhou, China
| | - Yuwei Pan
- Department of Medical Ultrasound, Guangzhou First People’s Hospital, Guangzhou, China
| | - Nina Xiao
- Department of Medical Ultrasound, Guangzhou First People’s Hospital, Guangzhou, China
| | - Jinglu Wei
- Department of Medical Ultrasound, Guangzhou First People’s Hospital, Guangzhou, China
| | - Shuyi Xiao
- Department of Medical Ultrasound, Guangzhou First People’s Hospital, Guangzhou, China
| | - Liping Chen
- Department of Medical Ultrasound, Guangzhou First People’s Hospital, Guangzhou, China
| | - Jianhua Liu
- Department of Medical Ultrasound, Guangzhou First People’s Hospital, Guangzhou, China
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53
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Himes BT, Zhang L, Daniels DJ. Treatment Strategies in Diffuse Midline Gliomas With the H3K27M Mutation: The Role of Convection-Enhanced Delivery in Overcoming Anatomic Challenges. Front Oncol 2019; 9:31. [PMID: 30800634 PMCID: PMC6375835 DOI: 10.3389/fonc.2019.00031] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Accepted: 01/11/2019] [Indexed: 12/30/2022] Open
Abstract
Diffuse midline gliomas harboring the H3 K27M mutation—including the previously named diffuse intrinsic pontine glioma (DIPG)—are lethal high-grade pediatric brain tumors that are inoperable and without cure. Despite numerous clinical trials, the prognosis remains poor, with a median survival of ~1 year from diagnosis. Systemic administration of chemotherapeutic agents is often hindered by the blood brain barrier (BBB), and even drugs that successfully cross the barrier may suffer from unpredictable distributions. The challenge in treating this deadly disease relies on effective delivery of a therapeutic agent to the bulk tumor as well as infiltrating cells. Therefore, methods that can enhance drug delivery to the brain are of great interest. Convection-enhanced delivery (CED) is a strategy that bypasses the BBB entirely and enhances drug distribution by applying hydraulic pressure to deliver agents directly and evenly into a target region. This technique reliably distributes infusate homogenously through the interstitial space of the target region and achieves high local drug concentrations in the brain. Moreover, recent studies have also shown that continuous delivery of drug over an extended period of time is safe, feasible, and more efficacious than standard single session CED. Therefore, CED represents a promising technique for treating midline tumors with the H3K27M mutation.
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Affiliation(s)
- Benjamin T Himes
- Department of Neurosurgery, Mayo Clinic, Rochester, MN, United States
| | - Liang Zhang
- Department of Neurosurgery, Mayo Clinic, Rochester, MN, United States
| | - David J Daniels
- Department of Neurosurgery, Mayo Clinic, Rochester, MN, United States.,Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, United States
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McMahon D, Poon C, Hynynen K. Evaluating the safety profile of focused ultrasound and microbubble-mediated treatments to increase blood-brain barrier permeability. Expert Opin Drug Deliv 2019; 16:129-142. [PMID: 30628455 DOI: 10.1080/17425247.2019.1567490] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
INTRODUCTION Treatment of several diseases of the brain are complicated by the presence of the skull and the blood-brain barrier (BBB). Focused ultrasound (FUS) and microbubble (MB)-mediated BBB treatment is a minimally invasive method to transiently increase the permeability of blood vessels in targeted brain areas. It can be used as a general delivery system to increase the concentration of therapeutic agents in the brain parenchyma. AREAS COVERED Over the past two decades, the safety of using FUS+MBs to deliver agents across the BBB has been interrogated through various methods of imaging, histology, biochemical assays, and behavior analyses. Here we provide an overview of the factors that affect the safety profile of these treatments, describe methods by which FUS+MB treatments are controlled, and discuss data that have informed the assessment of treatment risks. EXPERT OPINION There remains a need to assess the risks associated with clinically relevant treatment strategies, specifically repeated FUS+MB treatments, with and without therapeutic agent delivery. Additionally, efforts to develop metrics by which FUS+MB treatments can be easily compared across studies would facilitate a more rapid consensus on the risks associated with this intervention.
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Affiliation(s)
- Dallan McMahon
- a Physical Sciences Platform , Sunnybrook Research Institute , Toronto , ON , Canada.,b Department of Medical Biophysics , University of Toronto , Toronto , ON , Canada
| | - Charissa Poon
- a Physical Sciences Platform , Sunnybrook Research Institute , Toronto , ON , Canada.,c Institute of Biomaterials and Biomedical Engineering , University of Toronto , Toronto , ON , Canada
| | - Kullervo Hynynen
- a Physical Sciences Platform , Sunnybrook Research Institute , Toronto , ON , Canada.,b Department of Medical Biophysics , University of Toronto , Toronto , ON , Canada.,c Institute of Biomaterials and Biomedical Engineering , University of Toronto , Toronto , ON , Canada
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55
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Visscher M, Lajoinie G, Blazejewski E, Veldhuis G, Versluis M. Laser-activated microparticles for multimodal imaging: ultrasound and photoacoustics. Phys Med Biol 2019; 64:034001. [PMID: 30523821 DOI: 10.1088/1361-6560/aaf4a2] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The increasing personalization of medical treatment demands refined imaging and increased monitoring capabilities, as well as an improved efficacy through targeted drug delivery. Such a transition in health care can be facilitated by the use of multimodal contrast agents. In this paper, we present a novel type of multimodal contrast agents, that enhances contrast both in ultrasound and in photoacoustic imaging, while at the same time being capable of triggered drug delivery. Upon pulsed laser irradiation, polymeric microparticles-containing a dye and an oil core-can create a cavitation bubble that subsequently emits a strong acoustic wave. We investigated different formulations of these particles, by changing the oil content, dye concentration and probing conditions using a combination of pulsed laser excitation and an ultrasound chirp. We demonstrated that capsules with a core containing a low boiling point oil give the highest photoacoustic and acoustic response. The laser activation threshold for this system is high in the visible range, but within the near infrared medical limits. The same system also produces a stable bubble. US scattering by these stable bubbles results in medically relevant frequencies, making the particles of interest for biomedical and pre-clinical imaging. Finally, the system has potential to carry a functional drug-load, and a route to these applications is discussed.
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Affiliation(s)
- Mirjam Visscher
- Physics of Fluids Group, Technical Medical (TechMed) Centre and MESA+ Institute for Nanotechnology, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands. Department of Biomedical Engineering, Thorax Center, Erasmus University Medical Center, PO Box 2040, 3000 CA Rotterdam, The Netherlands
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Lee EJ, Fomenko A, Lozano AM. Magnetic Resonance-Guided Focused Ultrasound : Current Status and Future Perspectives in Thermal Ablation and Blood-Brain Barrier Opening. J Korean Neurosurg Soc 2018; 62:10-26. [PMID: 30630292 PMCID: PMC6328789 DOI: 10.3340/jkns.2018.0180] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Accepted: 11/13/2018] [Indexed: 02/06/2023] Open
Abstract
Magnetic resonance-guided focused ultrasound (MRgFUS) is an emerging new technology with considerable potential to treat various neurological diseases. With refinement of ultrasound transducer technology and integration with magnetic resonance imaging guidance, transcranial sonication of precise cerebral targets has become a therapeutic option. Intensity is a key determinant of ultrasound effects. High-intensity focused ultrasound can produce targeted lesions via thermal ablation of tissue. MRgFUS-mediated stereotactic ablation is non-invasive, incision-free, and confers immediate therapeutic effects. Since the US Food and Drug Administration approval of MRgFUS in 2016 for unilateral thalamotomy in medication-refractory essential tremor, studies on novel indications such as Parkinson's disease, psychiatric disease, and brain tumors are underway. MRgFUS is also used in the context of blood-brain barrier (BBB) opening at low intensities, in combination with intravenously-administered microbubbles. Preclinical studies show that MRgFUS-mediated BBB opening safely enhances the delivery of targeted chemotherapeutic agents to the brain and improves tumor control as well as survival. In addition, BBB opening has been shown to activate the innate immune system in animal models of Alzheimer's disease. Amyloid plaque clearance and promotion of neurogenesis in these studies suggest that MRgFUS-mediated BBB opening may be a new paradigm for neurodegenerative disease treatment in the future. Here, we review the current status of preclinical and clinical trials of MRgFUS-mediated thermal ablation and BBB opening, described their mechanisms of action, and discuss future prospects.
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Affiliation(s)
- Eun Jung Lee
- Toronto Western Research Institute, University Health Network, Toronto, Canada
| | - Anton Fomenko
- Toronto Western Research Institute, University Health Network, Toronto, Canada
| | - Andres M Lozano
- Toronto Western Research Institute, University Health Network, Toronto, Canada.,Division of Neurosurgery, Department of Surgery, Toronto Western Hospital, University of Toronto, Toronto, Canada
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57
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Souza RMDCE, da Silva ICS, Delgado ABT, da Silva PHV, Costa VRX. Focused ultrasound and Alzheimer's disease A systematic review. Dement Neuropsychol 2018; 12:353-359. [PMID: 30546844 PMCID: PMC6289486 DOI: 10.1590/1980-57642018dn12-040003] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Alzheimer’s disease (AD) affects millions of people, however, there is still no effective treatment. The use of focused ultrasound with microbubbles (FUS-MB) for the opening of the blood-brain barrier has been recently studied and may become a promising therapeutic target.
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Affiliation(s)
- Rodrigo Marmo da Costa E Souza
- Neurosurgeon. Departamento de Psicologia, Programa de Neurociências Cognitiva e do Comportamento, Universidade Federal da Paraíba, João Pessoa, Paraíba, Brazil.,Departamento de Medicina, Liga de Neurologia e Neurocirurgia Funcional da Paraíba, Cabedelo, PB, Brazil
| | - Inaê Carolline Silveira da Silva
- Medical student. Departamento de Medicina, Universidade Federal da Paraíba, João Pessoa, PB, Brazil.,Departamento de Medicina, Liga de Neurologia e Neurocirurgia Funcional da Paraíba, Cabedelo, PB, Brazil
| | - Anna Beatriz Temoteo Delgado
- Medical student. Departamento de Medicina, Faculdade de Ciências Médicas da Paraíba, Cabedelo, PB, Brazil.,Departamento de Medicina, Liga de Neurologia e Neurocirurgia Funcional da Paraíba, Cabedelo, PB, Brazil
| | - Pedro Hugo Vieira da Silva
- Medical student. Departamento de Medicina, Faculdade de Ciências Médicas da Paraíba, Cabedelo, PB, Brazil.,Departamento de Medicina, Liga de Neurologia e Neurocirurgia Funcional da Paraíba, Cabedelo, PB, Brazil
| | - Victor Ribeiro Xavier Costa
- Medical student. Departamento de Medicina, Faculdade de Ciências Médicas da Paraíba, Cabedelo, PB, Brazil.,Departamento de Medicina, Liga de Neurologia e Neurocirurgia Funcional da Paraíba, Cabedelo, PB, Brazil
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58
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Enhanced microbubble contrast agent oscillation following 250 kHz insonation. Sci Rep 2018; 8:16347. [PMID: 30397280 PMCID: PMC6218550 DOI: 10.1038/s41598-018-34494-5] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Accepted: 10/18/2018] [Indexed: 12/22/2022] Open
Abstract
Microbubble contrast agents are widely used in ultrasound imaging and therapy, typically with transmission center frequencies in the MHz range. Currently, an ultrasound center frequency near 250 kHz is proposed for clinical trials in which ultrasound combined with microbubble contrast agents is applied to open the blood brain barrier, since at this low frequency focusing through the human skull to a predetermined location can be performed with reduced distortion and attenuation compared to higher frequencies. However, the microbubble vibrational response has not yet been carefully evaluated at this low frequency (an order of magnitude below the resonance frequency of these contrast agents). In the past, it was assumed that encapsulated microbubble expansion is maximized near the resonance frequency and monotonically decreases with decreasing frequency. Our results indicated that microbubble expansion was enhanced for 250 kHz transmission as compared with the 1 MHz center frequency. Following 250 kHz insonation, microbubble expansion increased nonlinearly with increasing ultrasonic pressure, and was accurately predicted by either the modified Rayleigh-Plesset equation for a clean bubble or the Marmottant model of a lipid-shelled microbubble. The expansion ratio reached 30-fold with 250 kHz at a peak negative pressure of 400 kPa, as compared to a measured expansion ratio of 1.6 fold for 1 MHz transmission at a similar peak negative pressure. Further, the range of peak negative pressure yielding stable cavitation in vitro was narrow (~100 kPa) for the 250 kHz transmission frequency. Blood brain barrier opening using in vivo transcranial ultrasound in mice followed the same trend as the in vitro experiments, and the pressure range for safe and effective treatment was 75-150 kPa. For pressures above 150 kPa, inertial cavitation and hemorrhage occurred. Therefore, we conclude that (1) at this low frequency, and for the large oscillations, lipid-shelled microbubbles can be approximately modeled as clean gas microbubbles and (2) the development of safe and successful protocols for therapeutic delivery to the brain utilizing 250 kHz or a similar center frequency requires consideration of the narrow pressure window between stable and inertial cavitation.
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59
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Furtado D, Björnmalm M, Ayton S, Bush AI, Kempe K, Caruso F. Overcoming the Blood-Brain Barrier: The Role of Nanomaterials in Treating Neurological Diseases. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2018; 30:e1801362. [PMID: 30066406 DOI: 10.1002/adma.201801362] [Citation(s) in RCA: 327] [Impact Index Per Article: 54.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 04/09/2018] [Indexed: 05/24/2023]
Abstract
Therapies directed toward the central nervous system remain difficult to translate into improved clinical outcomes. This is largely due to the blood-brain barrier (BBB), arguably the most tightly regulated interface in the human body, which routinely excludes most therapeutics. Advances in the engineering of nanomaterials and their application in biomedicine (i.e., nanomedicine) are enabling new strategies that have the potential to help improve our understanding and treatment of neurological diseases. Herein, the various mechanisms by which therapeutics can be delivered to the brain are examined and key challenges facing translation of this research from benchtop to bedside are highlighted. Following a contextual overview of the BBB anatomy and physiology in both healthy and diseased states, relevant therapeutic strategies for bypassing and crossing the BBB are discussed. The focus here is especially on nanomaterial-based drug delivery systems and the potential of these to overcome the biological challenges imposed by the BBB. Finally, disease-targeting strategies and clearance mechanisms are explored. The objective is to provide the diverse range of researchers active in the field (e.g., material scientists, chemists, engineers, neuroscientists, and clinicians) with an easily accessible guide to the key opportunities and challenges currently facing the nanomaterial-mediated treatment of neurological diseases.
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Affiliation(s)
- Denzil Furtado
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, and the Department of Chemical Engineering, The University of Melbourne, Parkville, Victoria, 3010, Australia
| | - Mattias Björnmalm
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, and the Department of Chemical Engineering, The University of Melbourne, Parkville, Victoria, 3010, Australia
- Department of Materials, Department of Bioengineering, and the Institute of Biomedical Engineering, Imperial College London, London, SW7 2AZ, UK
| | - Scott Ayton
- Melbourne Dementia Research Centre, The Florey Institute for Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, 3052, Australia
| | - Ashley I Bush
- Melbourne Dementia Research Centre, The Florey Institute for Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, 3052, Australia
- Cooperative Research Center for Mental Health, Parkville, Victoria, 3052, Australia
| | - Kristian Kempe
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, and Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, 3052, Australia
| | - Frank Caruso
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, and the Department of Chemical Engineering, The University of Melbourne, Parkville, Victoria, 3010, Australia
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60
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Bretsztajn L, Gedroyc W. Brain-focussed ultrasound: what's the "FUS" all about? A review of current and emerging neurological applications. Br J Radiol 2018; 91:20170481. [PMID: 29419328 PMCID: PMC6221771 DOI: 10.1259/bjr.20170481] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Revised: 01/12/2018] [Accepted: 02/01/2018] [Indexed: 11/05/2022] Open
Abstract
MR-guided focussed ultrasound surgery (MRgFUS) allows for precise non-invasive thermal ablation of target tissues for a wide range of clinical applications. It is an innovative and rapidly expanding technology, which has already established itself as an effective and safe incisionless alternative in the treatment of various soft tissue tumours, with many more research studies underway to extend its therapeutic envelope. The non-invasiveness of the procedure makes FUS particularly attractive in functional neurosurgery, where existing treatment options are not suitable for all patients. Several clinical trials have demonstrated the feasibility and favourable safety profile of MR-guided focused ultrasound surgery in essential tremor, Parkinson's disease and other neurological conditions. This article reviews the existing evidence base for the neurological applications of FUS and the evidence for its emerging roles in the treatment of a range of brain disorders.
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Affiliation(s)
- Laure Bretsztajn
- Radiology Department, Imperial College Healthcare NHS Trust, London, United Kingdom
| | - Wladyslaw Gedroyc
- Radiology Department, Imperial College Healthcare NHS Trust, London, United Kingdom
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61
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Acoustic Emission-Feedback Planar Ultrasound System for Localized Blood–Brain Barrier Opening Monitoring. J Med Biol Eng 2018. [DOI: 10.1007/s40846-018-0406-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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62
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Ye D, Sultan D, Zhang X, Yue Y, Heo GS, Kothapalli SVVN, Luehmann H, Tai YC, Rubin JB, Liu Y, Chen H. Focused ultrasound-enabled delivery of radiolabeled nanoclusters to the pons. J Control Release 2018; 283:143-150. [PMID: 29864474 DOI: 10.1016/j.jconrel.2018.05.039] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Revised: 03/15/2018] [Accepted: 05/31/2018] [Indexed: 01/17/2023]
Abstract
The goal of this study was to establish the feasibility of integrating focused ultrasound (FUS)-mediated delivery of 64Cu-integrated gold nanoclusters (64Cu-AuNCs) to the pons for in vivo quantification of the nanocluster brain uptake using positron emission tomography (PET) imaging. FUS was targeted at the pons for the blood-brain barrier (BBB) disruption in the presence of systemically injected microbubbles, followed by the intravenous injection of 64Cu-AuNCs. The spatiotemporal distribution of the 64Cu-AuNCs in the brain was quantified using in vivo microPET/CT imaging at different time points post injection. Following PET imaging, the accumulation of radioactivity in the pons was further confirmed using autoradiography and gamma counting, and the gold concentration was quantified using inductively coupled plasma-mass spectrometry (ICP-MS). We found that the noninvasive and localized BBB opening by the FUS successfully delivered the 64Cu-AuNCs to the pons. We also demonstrated that in vivo real-time microPET/CT imaging was a reliable method for monitoring and quantifying the brain uptake of 64Cu-AuNCs delivered by the FUS. This drug delivery platform that integrates FUS, radiolabeled nanoclusters, and PET imaging provides a new strategy for noninvasive and localized nanoparticle delivery to the pons with concurrent in vivo quantitative imaging to evaluate delivery efficiency. The long-term goal is to apply this drug delivery platform to the treatment of pontine gliomas.
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Affiliation(s)
- Dezhuang Ye
- Department of Mechanical Engineering and Material Science, Washington University in St. Louis, Saint Louis, MO 63130, USA
| | - Deborah Sultan
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Xiaohui Zhang
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Yimei Yue
- Department of Biomedical Engineering, Washington University in St. Louis, Saint Louis, MO 63130, USA
| | - Gyu Seong Heo
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Satya V V N Kothapalli
- Department of Biomedical Engineering, Washington University in St. Louis, Saint Louis, MO 63130, USA
| | - Hannah Luehmann
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Yuan-Chuan Tai
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Joshua B Rubin
- Department of Pediatrics, Department of Neuroscience, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Yongjian Liu
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA.
| | - Hong Chen
- Department of Biomedical Engineering, Washington University in St. Louis, Saint Louis, MO 63130, USA; Department of Radiation Oncology, Washington University School of Medicine, Saint Louis, MO 63108, USA.
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Yoon K, Lee W, Croce P, Cammalleri A, Yoo SS. Multi-resolution simulation of focused ultrasound propagation through ovine skull from a single-element transducer. Phys Med Biol 2018; 63:105001. [PMID: 29658494 DOI: 10.1088/1361-6560/aabe37] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Transcranial focused ultrasound (tFUS) is emerging as a non-invasive brain stimulation modality. Complicated interactions between acoustic pressure waves and osseous tissue introduce many challenges in the accurate targeting of an acoustic focus through the cranium. Image-guidance accompanied by a numerical simulation is desired to predict the intracranial acoustic propagation through the skull; however, such simulations typically demand heavy computation, which warrants an expedited processing method to provide on-site feedback for the user in guiding the acoustic focus to a particular brain region. In this paper, we present a multi-resolution simulation method based on the finite-difference time-domain formulation to model the transcranial propagation of acoustic waves from a single-element transducer (250 kHz). The multi-resolution approach improved computational efficiency by providing the flexibility in adjusting the spatial resolution. The simulation was also accelerated by utilizing parallelized computation through the graphic processing unit. To evaluate the accuracy of the method, we measured the actual acoustic fields through ex vivo sheep skulls with different sonication incident angles. The measured acoustic fields were compared to the simulation results in terms of focal location, dimensions, and pressure levels. The computational efficiency of the presented method was also assessed by comparing simulation speeds at various combinations of resolution grid settings. The multi-resolution grids consisting of 0.5 and 1.0 mm resolutions gave acceptable accuracy (under 3 mm in terms of focal position and dimension, less than 5% difference in peak pressure ratio) with a speed compatible with semi real-time user feedback (within 30 s). The proposed multi-resolution approach may serve as a novel tool for simulation-based guidance for tFUS applications.
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Affiliation(s)
- Kyungho Yoon
- Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States of America
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Jones RM, Deng L, Leung K, McMahon D, O'Reilly MA, Hynynen K. Three-dimensional transcranial microbubble imaging for guiding volumetric ultrasound-mediated blood-brain barrier opening. Am J Cancer Res 2018; 8:2909-2926. [PMID: 29896293 PMCID: PMC5996357 DOI: 10.7150/thno.24911] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Accepted: 03/05/2018] [Indexed: 01/08/2023] Open
Abstract
Focused ultrasound (FUS)-mediated blood-brain barrier (BBB) opening recently entered clinical testing for targeted drug delivery to the brain. Sources of variability exist in the current procedures, motivating the development of real-time monitoring and control techniques to improve treatment safety and efficacy. Here we used three-dimensional (3D) transcranial microbubble imaging to calibrate FUS exposure levels for volumetric BBB opening. Methods: Using a sparse hemispherical transmit/receive ultrasound phased array, pulsed ultrasound was focused transcranially into the thalamus of rabbits during microbubble infusion and multi-channel 3D beamforming was performed online with receiver signals captured at the subharmonic frequency. Pressures were increased pulse-by-pulse until subharmonic activity was detected on acoustic imaging (psub), and tissue volumes surrounding the calibration point were exposed at 50-100%psub via rapid electronic beam steering. Results: Spatially-coherent subharmonic microbubble activity was successfully reconstructed transcranially in vivo during calibration sonications. Multi-point exposures induced volumetric regions of elevated BBB permeability assessed via contrast-enhanced magnetic resonance imaging (MRI). At exposure levels ≥75%psub, MRI and histological examination occasionally revealed tissue damage, whereas sonications at 50%psub were performed safely. Substantial intra-grid variability of FUS-induced bioeffects was observed via MRI, prompting future development of multi-point calibration schemes for improved treatment consistency. Receiver array sparsity and sensor configuration had substantial impacts on subharmonic detection sensitivity, and are factors that should be considered when designing next-generation clinical FUS brain therapy systems. Conclusion: Our findings suggest that 3D subharmonic imaging can be used to calibrate exposure levels for safe FUS-induced volumetric BBB opening, and should be explored further as a method for cavitation-mediated treatment guidance.
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65
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Izadifar Z, Babyn P, Chapman D. Ultrasound Cavitation/Microbubble Detection and Medical Applications. J Med Biol Eng 2018. [DOI: 10.1007/s40846-018-0391-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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66
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He Q, Liu J, Liang J, Liu X, Li W, Liu Z, Ding Z, Tuo D. Towards Improvements for Penetrating the Blood-Brain Barrier-Recent Progress from a Material and Pharmaceutical Perspective. Cells 2018; 7:cells7040024. [PMID: 29570659 PMCID: PMC5946101 DOI: 10.3390/cells7040024] [Citation(s) in RCA: 152] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 03/18/2018] [Accepted: 03/21/2018] [Indexed: 02/07/2023] Open
Abstract
The blood–brain barrier (BBB) is a critical biological structure that prevents damage to the brain and maintains its bathing microenvironment. However, this barrier is also the obstacle to deliver beneficial drugs to treat CNS (central nervous system) diseases. Many efforts have been made for improvement of delivering drugs across the BBB in recent years to treat CNS diseases. In this review, the anatomical and functional structure of the BBB is comprehensively discussed. The mechanisms of BBB penetration are summarized, and the methods and effects on increasing BBB permeability are investigated in detail. It also elaborates on the physical, chemical, biological and nanocarrier aspects to improve drug delivery penetration to the brain and introduces some specific drug delivery effects on BBB permeability.
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Affiliation(s)
- Quanguo He
- School of Life Science and Chemistry, Hunan University of Technology, Zhuzhou 412007, China.
| | - Jun Liu
- School of Life Science and Chemistry, Hunan University of Technology, Zhuzhou 412007, China.
| | - Jing Liang
- School of Life Science and Chemistry, Hunan University of Technology, Zhuzhou 412007, China.
| | - Xiaopeng Liu
- School of Life Science and Chemistry, Hunan University of Technology, Zhuzhou 412007, China.
| | - Wen Li
- School of Life Science and Chemistry, Hunan University of Technology, Zhuzhou 412007, China.
| | - Zhi Liu
- School of Life Science and Chemistry, Hunan University of Technology, Zhuzhou 412007, China.
| | - Ziyu Ding
- School of Life Science and Chemistry, Hunan University of Technology, Zhuzhou 412007, China.
| | - Du Tuo
- School of Life Science and Chemistry, Hunan University of Technology, Zhuzhou 412007, China.
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67
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Meng Y, Voisin MR, Suppiah S, Kalia SK, Kalia LV, Hamani C, Lipsman N. Is there a role for MR-guided focused ultrasound in Parkinson's disease? Mov Disord 2018; 33:575-579. [PMID: 29476631 DOI: 10.1002/mds.27308] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 12/13/2017] [Accepted: 12/17/2017] [Indexed: 01/17/2023] Open
Affiliation(s)
- Ying Meng
- Division of Neurosurgery, Sunnybrook Health Sciences Centre, Toronto, ON, Canada.,Department of Surgery, University of Toronto, Toronto, ON, Canada
| | - Mathew R Voisin
- Division of Neurosurgery, Sunnybrook Health Sciences Centre, Toronto, ON, Canada.,Department of Surgery, University of Toronto, Toronto, ON, Canada
| | - Suganth Suppiah
- Division of Neurosurgery, Sunnybrook Health Sciences Centre, Toronto, ON, Canada.,Department of Surgery, University of Toronto, Toronto, ON, Canada
| | - Suneil K Kalia
- Division of Neurosurgery, Toronto Western Hospital, Toronto, ON, Canada.,Department of Surgery, University of Toronto, Toronto, ON, Canada
| | - Lorraine V Kalia
- Krembil Research Institute, Toronto Western Hospital, University Health Network, 60 Leonard Ave Toronto, ON, Canada.,Morton and Gloria Shulman Movement Disorders Clinic and the Edmond J. Safra Program in Parkinson's Disease, Division of Neurology, Department of Medicine, Toronto Western Hospital, University Health Network, Toronto, ON, Canada.,Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada.,Division of Neurology, Department of Medicine, University of Toronto, Toronto, ON, Canada
| | - Clement Hamani
- Division of Neurosurgery, Sunnybrook Health Sciences Centre, Toronto, ON, Canada.,Department of Surgery, University of Toronto, Toronto, ON, Canada
| | - Nir Lipsman
- Division of Neurosurgery, Sunnybrook Health Sciences Centre, Toronto, ON, Canada.,Department of Surgery, University of Toronto, Toronto, ON, Canada
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Shekhar H, Smith NJ, Raymond JL, Holland CK. Effect of Temperature on the Size Distribution, Shell Properties, and Stability of Definity ®. ULTRASOUND IN MEDICINE & BIOLOGY 2018; 44:434-446. [PMID: 29174045 PMCID: PMC5759968 DOI: 10.1016/j.ultrasmedbio.2017.09.021] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 09/28/2017] [Accepted: 09/29/2017] [Indexed: 05/08/2023]
Abstract
Physical characterization of an ultrasound contrast agent (UCA) aids in its safe and effective use in diagnostic and therapeutic applications. The goal of this study was to investigate the impact of temperature on the size distribution, shell properties, and stability of Definity®, a U.S. Food and Drug Administration-approved UCA used for left ventricular opacification. A Coulter counter was modified to enable particle size measurements at physiologic temperatures. The broadband acoustic attenuation spectrum and size distribution of Definity® were measured at room temperature (25 °C) and physiologic temperature (37 °C) and were used to estimate the viscoelastic shell properties of the agent at both temperatures. Attenuation and size distribution was measured over time to assess the effect of temperature on the temporal stability of Definity®. The attenuation coefficient of Definity® at 37 °C was as much as 5 dB higher than the attenuation coefficient measured at 25 °C. However, the size distributions of Definity® at 25 °C and 37 °C were similar. The estimated shell stiffness and viscosity decreased from 1.76 ± 0.18 N/m and 0.21 × 10-6 ± 0.07 × 10-6 kg/s at 25 °C to 1.01 ± 0.07 N/m and 0.04 × 10-6 ± 0.04 × 10-6 kg/s at 37 °C, respectively. Size-dependent differences in dissolution rates were observed within the UCA population at both 25 °C and 37 °C. Additionally, cooling the diluted UCA suspension from 37 °C to 25 °C accelerated the dissolution rate. These results indicate that although temperature affects the shell properties of Definity® and can influence the stability of Definity®, the size distribution of this agent is not affected by a temperature increase from 25 °C to 37 °C.
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Affiliation(s)
- Himanshu Shekhar
- Division of Cardiovascular Health and Disease, Department of Internal Medicine, University of Cincinnati, Cincinnati, Ohio, USA.
| | - Nathaniel J Smith
- Division of Cardiovascular Health and Disease, Department of Internal Medicine, University of Cincinnati, Cincinnati, Ohio, USA
| | - Jason L Raymond
- Department of Engineering Science, University of Oxford, Oxford, UK
| | - Christy K Holland
- Division of Cardiovascular Health and Disease, Department of Internal Medicine, University of Cincinnati, Cincinnati, Ohio, USA; Department of Biomedical Engineering, University of Cincinnati, Cincinnati, Ohio, USA
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Fu BM. Transport Across the Blood-Brain Barrier. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1097:235-259. [PMID: 30315549 DOI: 10.1007/978-3-319-96445-4_13] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The blood-brain barrier (BBB) is a dynamic barrier essential for maintaining the microenvironment of the brain. Although the special anatomical features of the BBB determine its protective role for the central nervous system (CNS) from blood-borne neurotoxins, however, the BBB extremely limits the therapeutic efficacy of drugs into the CNS, which greatly hinders the treatment of major brain diseases. This chapter summarized the unique structures of the BBB; described a variety of in vivo and in vitro experimental methods for determining the transport properties of the BBB and the permeability of the BBB to water, ions, and solutes including nutrients, therapeutic agents, and drug carriers; and presented recently developed mathematical models which quantitatively correlate the anatomical structures of the BBB with its barrier functions. Recent findings for modulation of the BBB permeability by chemical and physical stimuli were described. Finally, drug delivery strategies through specific trans-BBB routes were discussed.
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Affiliation(s)
- Bingmei M Fu
- Department of Biomedical Engineering, The City College of the City University of New York, New York, NY, USA.
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70
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Alecou T, Giannakou M, Damianou C. Amyloid β Plaque Reduction With Antibodies Crossing the Blood-Brain Barrier, Which Was Opened in 3 Sessions of Focused Ultrasound in a Rabbit Model. JOURNAL OF ULTRASOUND IN MEDICINE : OFFICIAL JOURNAL OF THE AMERICAN INSTITUTE OF ULTRASOUND IN MEDICINE 2017; 36:2257-2270. [PMID: 28543446 DOI: 10.1002/jum.14256] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Revised: 01/18/2017] [Accepted: 02/08/2017] [Indexed: 05/28/2023]
Abstract
OBJECTIVES The main objective of this study was to remove amyloid β plaques by applying multiple sessions of focused ultrasound (US)-induced blood-brain barrier (BBB) opening using microbubbles with and without delivery of antibodies in a rabbit model. METHODS The animal model was achieved by feeding a high-cholesterol diet to rabbits for 4 months. Fifty-two New Zealand White rabbits were divided into treatment groups: untreated control, high-cholesterol diet only, antibodies only, focused US only, and focused US and antibodies. Three sessions of focused US were administered to the treatment groups. RESULTS It was shown that with this animal model, the plaques were 30 μm in diameter. By increasing the number of sessions, the number of plaques decreased (both for focused US only and focused US and antibodies). Without the application of focused US, the average number of plaques dropped from 200/cm2 (before treatment) to 170/cm2 (after treatment). The effect of treatment with focused US with antibodies was more drastic. With 3 BBB opening sessions, the average number of plaques was reduced from 200 to 78/cm2 . CONCLUSIONS This feasibility study had demonstrated that by opening the BBB, it will be possible to deliver exogenous antibodies to the brain, thus eliminating amyloid β plaques. More importantly with repeated opening of the BBB (3 times in this study), the reduction in the number of plaques was increased.
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Affiliation(s)
- Tereza Alecou
- Department of Electrical Engineering, Cyprus University of Technology, Limassol, Cyprus
| | - Marinos Giannakou
- Department of Electrical Engineering, Cyprus University of Technology, Limassol, Cyprus
| | - Christakis Damianou
- Department of Electrical Engineering, Cyprus University of Technology, Limassol, Cyprus
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71
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Volz KR, Evans KD, Kanner CD, Buford JA, Freimer M, Sommerich CM, Basso DM. Molecular Ultrasound Imaging for the Detection of Neural Inflammation: A Longitudinal Dosing Pilot Study. JOURNAL OF DIAGNOSTIC MEDICAL SONOGRAPHY 2017. [DOI: 10.1177/8756479317736250] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Molecular ultrasound imaging provides the ability to detect physiologic processes noninvasively by targeting a variety of biomarkers in vivo. The current study was performed by exploiting an inflammatory biomarker, P-selectin, known to be present following spinal cord injury. Using a murine model (n = 6), molecular ultrasound imaging was performed using contrast microbubbles modified to target and adhere to P-selectin, prior to spinal cord injury (0D), acute stage postinjury (7D), and chronic stage (42D). Additionally, two imaging sessions were performed on each subject at specific time points, using doses of 30 μL and 100 μL. Upon analysis, targeted contrast analysis parameters were appreciably increased during the 7D scan compared with the 42D scan, without statistical significance. When examining the dose levels, the 30-μL dose demonstrated greater values than the 100-μL dose but lacked statistical significance. These findings provide additional preclinical evidence for the use of molecular ultrasound imaging for the possible detection of inflammation.
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Affiliation(s)
- Kevin R. Volz
- College of Medicine, The Ohio State University, Columbus, OH, USA
| | - Kevin D. Evans
- College of Medicine, The Ohio State University, Columbus, OH, USA
| | | | - John A. Buford
- College of Medicine, The Ohio State University, Columbus, OH, USA
| | - Miriam Freimer
- College of Medicine, The Ohio State University, Columbus, OH, USA
| | | | - D. Michele Basso
- College of Medicine, The Ohio State University, Columbus, OH, USA
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Liu M, Jevtic S, Markham-Coultes K, Ellens NPK, O'Reilly MA, Hynynen K, Aubert I, McLaurin J. Investigating the efficacy of a combination Aβ-targeted treatment in a mouse model of Alzheimer's disease. Brain Res 2017; 1678:138-145. [PMID: 29066368 DOI: 10.1016/j.brainres.2017.10.015] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Revised: 09/28/2017] [Accepted: 10/15/2017] [Indexed: 11/28/2022]
Abstract
Amyloid-beta peptide (Aβ) plays a critical role in the pathogenesis of Alzheimer's disease (AD). Here, we explored the use of a combination treatment to reduce amyloid load through microglial phagocytosis in a mouse model of AD. We hypothesized that using an initial treatment of magnetic resonance image guided focused ultrasound (MRIgFUS) to transiently increase the blood-brain barrier (BBB) permeability and enhance the delivery of an Aβ-antibody (BAM-10), followed by scyllo-inositol treatment would result in accelerated clearance. TgCRND8 mice expressing both Swedish (KM670/671NL) and Indiana (V717F) APP mutations under the hamster prion (PrP) promoter at 5 months of age were either treated with scyllo-inositol or received an initial MRIgFUS treatment delivering BAM-10 prior to scyllo-inositol treatment for one month. Treated animals and untreated TgCRND8 littermates were then sacrificed at 6 months of age, and their brains were processed for immunohistochemistry and immunofluorescence. Amyloid load was quantified and analyzed through immunohistochemical staining. Astrocyte and microglial activation were quantified and analyzed through immunofluorescent staining. We found that both the scyllo-inositol treatment and combination treatment, MRIgFUS/BAM10+scyllo-inositol, significantly reduced amyloid load and astrocyte activation in the hippocampus and the cortex. Furthermore, in both treatment paradigms microglial activation and phagocytosis was increased in comparison to the untreated mice. There were no differences detected between the two treatment paradigms. We propose that the 30-day scyllo-inositol treatment saturated the early benefit of the MRIgFUS/BAM-10 treatment. In the future, multiple FUS treatments combined with BAM-10 throughout the duration of scyllo-inositol treatment may lead to more effective amyloid clearance.
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Affiliation(s)
- Mingzhe Liu
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada; Hurvitz Brain Sciences Research Program, Biological Sciences, Sunnybrook Research Institute, Toronto, ON, Canada
| | - Stefan Jevtic
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada; Hurvitz Brain Sciences Research Program, Biological Sciences, Sunnybrook Research Institute, Toronto, ON, Canada
| | - Kelly Markham-Coultes
- Hurvitz Brain Sciences Research Program, Biological Sciences, Sunnybrook Research Institute, Toronto, ON, Canada
| | - Nicholas P K Ellens
- Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada; Physical Sciences, Sunnybrook Research Institute, Toronto, ON, Canada
| | - Meaghan A O'Reilly
- Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada; Physical Sciences, Sunnybrook Research Institute, Toronto, ON, Canada
| | - Kullervo Hynynen
- Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada; Physical Sciences, Sunnybrook Research Institute, Toronto, ON, Canada
| | - Isabelle Aubert
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada; Hurvitz Brain Sciences Research Program, Biological Sciences, Sunnybrook Research Institute, Toronto, ON, Canada
| | - JoAnne McLaurin
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada; Hurvitz Brain Sciences Research Program, Biological Sciences, Sunnybrook Research Institute, Toronto, ON, Canada.
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Meng Y, Suppiah S, Mithani K, Solomon B, Schwartz ML, Lipsman N. Current and emerging brain applications of MR-guided focused ultrasound. J Ther Ultrasound 2017; 5:26. [PMID: 29034095 PMCID: PMC5629772 DOI: 10.1186/s40349-017-0105-z] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Accepted: 09/28/2017] [Indexed: 12/30/2022] Open
Abstract
MRI guided focused ultrasound is an emerging technique that uses acoustic energy to noninvasively treat intracranial disorders. At high frequencies, it can be used to raise tissue temperatures and ablate discrete brain targets with sub-millimeter accuracy. This application is currently under investigation for a broad range of clinical applications, including brain tumors, movement disorders, and psychiatric conditions. At low frequencies MRI guided focused ultrasound can be used to modulate neuronal activity and in conjunction with injected microbubbles, can open the blood-brain barrier to enhance the delivery of therapeutic compounds. The last decade has seen dramatic advances in the science of MRI guided focused ultrasound, helping elucidate both its mechanisms and potential in pre-clinical models, and its translational promise across myriad clinical applications. This review provides an update of current and emerging MRI guided focused ultrasound applications for intracranial disorders and describes future directions and challenges for the field.
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Affiliation(s)
- Ying Meng
- Division of Neurosurgery, Department of Surgery, Sunnybrook Health Sciences Centre, University of Toronto, 2075 Bayview Avenue, Toronto, ON Canada
| | - Suganth Suppiah
- Division of Neurosurgery, Department of Surgery, Sunnybrook Health Sciences Centre, University of Toronto, 2075 Bayview Avenue, Toronto, ON Canada
| | - Karim Mithani
- Physical Sciences Platform, Sunnybrook Research Institute, Toronto, ON Canada
| | - Benjamin Solomon
- Physical Sciences Platform, Sunnybrook Research Institute, Toronto, ON Canada
| | - Michael L Schwartz
- Division of Neurosurgery, Department of Surgery, Sunnybrook Health Sciences Centre, University of Toronto, 2075 Bayview Avenue, Toronto, ON Canada
| | - Nir Lipsman
- Division of Neurosurgery, Department of Surgery, Sunnybrook Health Sciences Centre, University of Toronto, 2075 Bayview Avenue, Toronto, ON Canada.,Physical Sciences Platform, Sunnybrook Research Institute, Toronto, ON Canada
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Askoxylakis V, Arvanitis CD, Wong CSF, Ferraro GB, Jain RK. Emerging strategies for delivering antiangiogenic therapies to primary and metastatic brain tumors. Adv Drug Deliv Rev 2017. [PMID: 28648712 DOI: 10.1016/j.addr.2017.06.011] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Five-year survival rates have not increased appreciably for patients with primary and metastatic brain tumors. Nearly 17,000 patients die from primary brain tumors, whereas approximately 200,000 cases are diagnosed with brain metastasis every year in the US alone. At the same time, with improved control of systemic disease, the incidence of brain metastasis is increasing. Thus, novel approaches for improving the treatment outcome for these uniformly fatal diseases are needed urgently. In the review, we summarize the challenges in the treatment of these diseases using antiangiogenic therapies alone or in combination with radio-, chemo- and immuno-therapies. We also discuss the emerging strategies to improve the treatment outcome using both pharmacological approaches to normalize the tumor microenvironment and physical approaches (e.g., focused ultrasound) to modulate the blood-tumor-barrier, along with limitations of each approach. Finally, we offer some new avenues of future research.
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Affiliation(s)
- Vasileios Askoxylakis
- Edwin L. Steele Laboratories, Department of Radiation Oncology, Massachusetts General Hospital (MGH), Harvard Medical School (HMS), Boston, MA, 02114, USA
| | - Costas D Arvanitis
- School of Mechanical Engineering, Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Christina S F Wong
- Edwin L. Steele Laboratories, Department of Radiation Oncology, Massachusetts General Hospital (MGH), Harvard Medical School (HMS), Boston, MA, 02114, USA
| | - Gino B Ferraro
- Edwin L. Steele Laboratories, Department of Radiation Oncology, Massachusetts General Hospital (MGH), Harvard Medical School (HMS), Boston, MA, 02114, USA
| | - Rakesh K Jain
- Edwin L. Steele Laboratories, Department of Radiation Oncology, Massachusetts General Hospital (MGH), Harvard Medical School (HMS), Boston, MA, 02114, USA.
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Hsu YH, Liu RS, Lin WL, Yuh YS, Lin SP, Wong TT. Transcranial pulsed ultrasound facilitates brain uptake of laronidase in enzyme replacement therapy for Mucopolysaccharidosis type I disease. Orphanet J Rare Dis 2017; 12:109. [PMID: 28595620 PMCID: PMC5465581 DOI: 10.1186/s13023-017-0649-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Accepted: 05/11/2017] [Indexed: 12/31/2022] Open
Abstract
Background Mucopolysaccharidosis type I (MPS I) is a debilitating hereditary disease characterized by alpha-L-iduronidase (IDUA) deficiency and consequent inability to degrade glycosaminoglycans. The pathological accumulation of glycosaminoglycans systemically results in severe mental retardation and multiple organ dysfunction. Enzyme replacement therapy with recombinant human alpha-L-iduronidase (rhIDU) improves the function of some organs but not neurological deficits owing to its exclusion from the brain by the blood-brain barrier (BBB). Methods We divided MPS I mice into control group, enzyme replacement group with rhIDU 2.9 mg/kg injection, enzyme replacement with one-spot ultrasound treatment group, and enzyme replacement with two-spot ultrasound treatment group, and compare treatment effectiveness between groups. All ultrasound treatments were applied on left side brain. Evans blue was used to simulate the distribution of rhIDU in the brain. Results Transcranial pulsed weakly focused ultrasound combined with microbubbles facilitates brain rhIDU delivery in MPS I mice receiving systemic enzyme replacement therapy. With intravenously injected rhIDU 2.9 mg/kg, the IDUA enzyme activity on the ultrasound treated side of the cerebral hemisphere raised to 7.81-fold that on the untreated side and to 75.84% of its normal value. Evans blue simulation showed the distribution of the delivered drug was extensive, involving a large volume of the treated cerebral hemisphere. Two-spot ultrasound treatment scheme is more efficient for brain rhIDU delivery than one-spot ultrasound treatment scheme. Conclusions Transcranial pulsed weakly focused ultrasound can open BBB extensively and facilitates brain rhIDU delivery. This novel technology may provide a new MPS I treatment strategy.
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Affiliation(s)
- Yu-Hone Hsu
- Institute of Biomedical Engineering, College of Medicine and College of Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei, 10617, Taiwan.,Department of Neurosurgery, Cheng-Hsin General Hospital, Taipei, Taiwan
| | - Ren-Shyan Liu
- Biomedical Imaging and Radiological Sciences, National Yang-Ming University, No.155, Sec.2, Linong Street, Taipei, 112, Taiwan.,National PET/Cyclotron Center, Department of Nuclear Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.,Molecular and Genetic Imaging Core/Taiwan Mouse Clinic, National Comprehensive Mouse Phenotyping and Drug Testing Center, Taipei, Taiwan
| | - Win-Li Lin
- Institute of Biomedical Engineering, College of Medicine and College of Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei, 10617, Taiwan.,Institute of Biomedical Engineering and Nanomedicine, National Health Research Institutes, Miaoli, Taiwan
| | - Yeong-Seng Yuh
- Department of Pediatrics, Cheng-Hsin General Hospital, No.45, Cheng Hsin St., Pai-Tou, Taipei, 112, Taiwan.,Department of Pediatrics, National Defense Medical Center, Taipei, Taiwan
| | - Shuan-Pei Lin
- Department of Medicine, MacKay Medical College, New Taipei City, Taiwan.,Department of Pediatrics, MacKay Memorial Hospital, No. 92, Sec. 2 Chung-Shan North Road, Taipei, 10449, Taiwan.,Department of Medical Research, MacKay Memorial Hospital, No. 92, Sec. 2 Chung-Shan North Road, Taipei, 10449, Taiwan.,Department of Early Childhood Care, National Taipei University of Nursing and Health Sciences, Taipei, Taiwan
| | - Tai-Tong Wong
- Division of Pediatric Neurosurgery, Neurological Institute, Taipei Veterans General Hospital, Taipei, Taiwan. .,Institutes of Clinical Medicine, Taipei Medical University, Taipei, Taiwan. .,Division of Pediatric Neurosurgery, Department of Neurosurgery, Taipei Medical University Hospital, Taipei Medical University, 252 Wuxing St, Taipei, 11031, Taiwan. .,Joint Biobank, Office of Human Research, Taipei Medical University, Taipei, Taiwan.
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Chakroun RW, Zhang P, Lin R, Schiapparelli P, Quinones-Hinojosa A, Cui H. Nanotherapeutic systems for local treatment of brain tumors. WILEY INTERDISCIPLINARY REVIEWS-NANOMEDICINE AND NANOBIOTECHNOLOGY 2017; 10. [PMID: 28544801 DOI: 10.1002/wnan.1479] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 04/14/2017] [Accepted: 04/18/2017] [Indexed: 12/31/2022]
Abstract
Malignant brain tumor, including the most common type glioblastoma, are histologically heterogeneous and invasive tumors known as the most devastating neoplasms with high morbidity and mortality. Despite multimodal treatment including surgery, radiotherapy, chemotherapy, and immunotherapy, the disease inevitably recurs and is fatal. This lack of curative options has motivated researchers to explore new treatment strategies and to develop new drug delivery systems (DDSs); however, the unique anatomical, physiological, and pathological features of brain tumors greatly limit the effectiveness of conventional chemotherapy. In this context, we review the recent progress in the development of nanoparticle-based DDSs aiming to address the key challenges in transporting sufficient amount of therapeutic agents into the brain tumor areas while minimizing the potential side effects. We first provide an overview of the standard treatments currently used in the clinic for the management of brain cancers, discussing the effectiveness and limitations of each therapy. We then provide an in-depth review of nanotherapeutic systems that are intended to bypass the blood-brain barrier, overcome multidrug resistance, infiltrate larger tumorous tissue areas, and/or release therapeutic agents in a controlled manner. WIREs Nanomed Nanobiotechnol 2018, 10:e1479. doi: 10.1002/wnan.1479 This article is categorized under: Implantable Materials and Surgical Technologies > Nanomaterials and Implants Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.
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Affiliation(s)
- Rami Walid Chakroun
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Pengcheng Zhang
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Ran Lin
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD, USA
| | | | | | - Honggang Cui
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD, USA
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Güvener N, Appold L, de Lorenzi F, Golombek SK, Rizzo LY, Lammers T, Kiessling F. Recent advances in ultrasound-based diagnosis and therapy with micro- and nanometer-sized formulations. Methods 2017; 130:4-13. [PMID: 28552267 DOI: 10.1016/j.ymeth.2017.05.018] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 05/11/2017] [Accepted: 05/21/2017] [Indexed: 01/15/2023] Open
Abstract
Ultrasound (US) is one of the most frequently used imaging methods in the clinic. The broad spectrum of its applications can be increased by the use of gas-filled microbubbles (MB) as ultrasound contrast agents (UCA). In recent years, also nanoscale UCA like nanobubbles (NB), echogenic liposomes (ELIP) and nanodroplets have been developed, which in contrast to MB, are able to extravasate from the vessels into the tissue. New disease-specific UCA have been designed for the assessment of tissue biomarkers and advanced US to a molecular imaging modality. For this purpose, specific binding moieties were coupled to the UCA surface. The vascular endothelial growth factor receptor-2 (VEGFR-2) and P-/E-selectin are prominent examples of molecular US targets to visualize tumor blood vessels and inflammatory diseases, respectively. Besides their application in contrast-enhanced imaging, MB can also be employed for drug delivery to tumors and across the blood-brain barrier (BBB). This review summarizes the development of micro- and nanoscaled UCA and highlights recent advances in diagnostic and therapeutic applications, which are ready for translation into the clinic.
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Affiliation(s)
- Nihan Güvener
- Institute for Experimental Molecular Imaging, University Clinic and Helmholtz Institute for Biomedical Engineering, RWTH Aachen University, Pauwelsstrasse 20, 52074 Aachen, Germany
| | - Lia Appold
- Institute for Experimental Molecular Imaging, University Clinic and Helmholtz Institute for Biomedical Engineering, RWTH Aachen University, Pauwelsstrasse 20, 52074 Aachen, Germany
| | - Federica de Lorenzi
- Institute for Experimental Molecular Imaging, University Clinic and Helmholtz Institute for Biomedical Engineering, RWTH Aachen University, Pauwelsstrasse 20, 52074 Aachen, Germany
| | - Susanne K Golombek
- Institute for Experimental Molecular Imaging, University Clinic and Helmholtz Institute for Biomedical Engineering, RWTH Aachen University, Pauwelsstrasse 20, 52074 Aachen, Germany
| | - Larissa Y Rizzo
- Institute for Experimental Molecular Imaging, University Clinic and Helmholtz Institute for Biomedical Engineering, RWTH Aachen University, Pauwelsstrasse 20, 52074 Aachen, Germany
| | - Twan Lammers
- Institute for Experimental Molecular Imaging, University Clinic and Helmholtz Institute for Biomedical Engineering, RWTH Aachen University, Pauwelsstrasse 20, 52074 Aachen, Germany
| | - Fabian Kiessling
- Institute for Experimental Molecular Imaging, University Clinic and Helmholtz Institute for Biomedical Engineering, RWTH Aachen University, Pauwelsstrasse 20, 52074 Aachen, Germany.
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78
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Biological effects of blood-brain barrier disruption using a focused ultrasound. Biomed Eng Lett 2017; 7:115-120. [PMID: 30603158 DOI: 10.1007/s13534-017-0025-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 02/19/2017] [Accepted: 03/24/2017] [Indexed: 01/06/2023] Open
Abstract
With focused ultrasound (FUS) and microbubbles, BBB can be transiently disrupted with a localized and non-invasive approach. BBB disruption induced by FUS has made progressions to move forward on delivery of therapeutic agents into a brain in a specific area of brain for better treatment of neurological diseases. In addition to be used as an improvement of drug delivery, BBB disruption has been found to induce biological effects such as a clearance of protein aggregation which cause Alzheimer's disease, regulation of proteins which facilitate drug uptake, and modulation of neuronal function and neurogenesis. In this review, we discuss overview about the principles of BBB opening with FUS and milestones in these biological effects of FUS-induced BBB disruption.
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79
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Song Z, Wang Z, Shen J, Xu S, Hu Z. Nerve growth factor delivery by ultrasound-mediated nanobubble destruction as a treatment for acute spinal cord injury in rats. Int J Nanomedicine 2017; 12:1717-1729. [PMID: 28280337 PMCID: PMC5340249 DOI: 10.2147/ijn.s128848] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Background Spinal cord injuries (SCIs) can cause severe disability or death. Treatment options include surgical intervention, drug therapy, and stem cell transplantation. However, the efficacy of these methods for functional recovery remains unsatisfactory. Purpose This study was conducted to explore the effect of ultrasound (US)-mediated destruction of poly(lactic-co-glycolic acid) (PLGA) nanobubbles (NBs) expressing nerve growth factor (NGF) (NGF/PLGA NBs) on nerve regeneration in rats following SCI. Materials and methods Adult male Sprague Dawley rats were randomly divided into four treatment groups after Allen hit models of SCI were established. The groups were normal saline (NS) group, NGF and NBs group, NGF and US group, and NGF/PLGA NBs and US group. Histological changes after SCI were observed by hematoxylin and eosin staining. Neuron viability was determined by Nissl staining. Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling staining was used to examine cell apoptosis. NGF gene and protein expressions were detected by quantitative reverse transcription polymerase chain reaction and Western blotting. Green fluorescent protein expression in the spinal cord was examined using an inverted fluorescence microscope. The recovery of neural function was determined using the Basso, Beattie, and Bresnahan test. Results NGF therapy using US-mediated NGF/PLGA NBs destruction significantly increased NGF expression, attenuated histological injury, decreased neuron loss, inhibited neuronal apoptosis in injured spinal cords, and increased BBB scores in rats with SCI. Conclusion US-mediated NGF/PLGA NBs destruction effectively transfects the NGF gene into target tissues and has a significant effect on the injured spinal cord. The combination of US irradiation and gene therapy through NGF/PLGA NBs holds great promise for the future of nanomedicine and the development of noninvasive treatment options for SCI and other diseases.
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Affiliation(s)
- Zhaojun Song
- Department of Orthopedics, The First Affiliated Hospital
| | - Zhigang Wang
- Institution of Ultrasound Imaging, The Second Affiliated Hospital, Chongqing Medical University, Chongqing, People's Republic of China
| | - Jieliang Shen
- Department of Orthopedics, The First Affiliated Hospital
| | - Shengxi Xu
- Department of Orthopedics, The First Affiliated Hospital
| | - Zhenming Hu
- Department of Orthopedics, The First Affiliated Hospital
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O'Reilly MA, Hough O, Hynynen K. Blood-Brain Barrier Closure Time After Controlled Ultrasound-Induced Opening Is Independent of Opening Volume. JOURNAL OF ULTRASOUND IN MEDICINE : OFFICIAL JOURNAL OF THE AMERICAN INSTITUTE OF ULTRASOUND IN MEDICINE 2017; 36:475-483. [PMID: 28108988 PMCID: PMC5319892 DOI: 10.7863/ultra.16.02005] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 06/03/2016] [Indexed: 05/15/2023]
Abstract
OBJECTIVES Microbubble-mediated focused ultrasound (US) opening of the blood-brain barrier (BBB) has shown promising results for the treatment of brain tumors and conditions such as Alzheimer disease. Practical clinical implementation of focused US treatments would aim to treat a substantial portion of the brain; thus, the safety of opening large volumes must be investigated. This study investigated whether the opened volume affects the time for the BBB to be restored after treatment. METHODS Sprague Dawley rats (n = 5) received bilateral focused US treatments. One hemisphere received a single sonication, and the contralateral hemisphere was targeted with 4 overlapping foci. Contrast-enhanced T1-weighted magnetic resonance imaging was used to assess the integrity of the BBB at 0, 6, and 24 hours after focused US. RESULTS At time 0, there was no significant difference in the mean enhancement between the single- and multi-point sonications (mean ± SD, 29.7% ± 18.4% versus 29.7% ± 24.1%; P = .9975). The mean cross-sectional area of the BBB opening resulting from the multi-point sonication was approximately 3.5-fold larger than that of the single-point case (14.2 ± 4.7 versus 4.1 ± 3.3 mm2 ; P < .0001). The opened volumes in 9 of 10 hemispheres were closed by 6 hours after focused US. The remaining treatment location had substantially reduced enhancement at 6 hours and was closed by 24 hours. Histologic analysis revealed small morphologic changes associated with this location. T2-weighted images at 6 and 24 hours showed no signs of edema. T2*-weighted images obtained at 6 hours also showed no signs hemorrhage in any animal. CONCLUSIONS The time for the BBB to close after focused US was independent of the opening volume on the time scale investigated. No differences in treatment effects were observable by magnetic resonance imaging follow-up between larger- and smaller-volume sonications, suggesting that larger-volume BBB opening can be performed safely.
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Affiliation(s)
- Meaghan A O'Reilly
- Physical Sciences Platform, Sunnybrook Research Institute, Toronto, Ontario, Canada
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
| | - Olivia Hough
- Physical Sciences Platform, Sunnybrook Research Institute, Toronto, Ontario, Canada
| | - Kullervo Hynynen
- Physical Sciences Platform, Sunnybrook Research Institute, Toronto, Ontario, Canada
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
- Department of Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
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81
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Fang F, Zou D, Wang W, Yin Y, Yin T, Hao S, Wang B, Wang G, Wang Y. Non-invasive approaches for drug delivery to the brain based on the receptor mediated transport. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2017; 76:1316-1327. [PMID: 28482500 DOI: 10.1016/j.msec.2017.02.056] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2016] [Revised: 12/13/2016] [Accepted: 02/14/2017] [Indexed: 10/20/2022]
Abstract
The blood brain barrier (BBB) is a physical and biochemical barrier that prevents entry of toxic compounds into brain for preserving homeostasis. However, the BBB also strictly limits influx of most therapeutic agents into the brain. One promising method for overcoming this problem to deliver drugs is receptor mediated transport (RMT) system, which employs the vesicular trafficking machinery to transport substrates across the BBB endothelium in a noninvasive manner. The conjugates of drug or drug-loaded vector linked with appropriate ligands specifically binds to the endogenous targeting receptor on the surface of the endothelial cells. Then drugs could enter the cell body by means of transcytosis and eventual releasing into the brain parenchyma. Over the past 20years, there have been significant developments of RMT targeting strategies. Here, we will review the recent advance of various promising RMT systems and discuss the capability of these approaches for drug delivery to the brain.
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Affiliation(s)
- Fei Fang
- Key Laboratory of Bio-rheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Shapingba Street 174, Chongqing 404100, China
| | - Dan Zou
- Key Laboratory of Bio-rheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Shapingba Street 174, Chongqing 404100, China
| | - Wei Wang
- Key Laboratory of Bio-rheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Shapingba Street 174, Chongqing 404100, China
| | - Ying Yin
- Key Laboratory of Bio-rheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Shapingba Street 174, Chongqing 404100, China
| | - Tieying Yin
- Key Laboratory of Bio-rheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Shapingba Street 174, Chongqing 404100, China
| | - Shilei Hao
- Key Laboratory of Bio-rheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Shapingba Street 174, Chongqing 404100, China
| | - Bochu Wang
- Key Laboratory of Bio-rheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Shapingba Street 174, Chongqing 404100, China
| | - Guixue Wang
- Key Laboratory of Bio-rheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Shapingba Street 174, Chongqing 404100, China
| | - Yazhou Wang
- Key Laboratory of Bio-rheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Shapingba Street 174, Chongqing 404100, China.
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82
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Tosi U, Marnell CS, Chang R, Cho WC, Ting R, Maachani UB, Souweidane MM. Advances in Molecular Imaging of Locally Delivered Targeted Therapeutics for Central Nervous System Tumors. Int J Mol Sci 2017; 18:ijms18020351. [PMID: 28208698 PMCID: PMC5343886 DOI: 10.3390/ijms18020351] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Revised: 12/19/2016] [Accepted: 01/26/2017] [Indexed: 12/24/2022] Open
Abstract
Thanks to the recent advances in the development of chemotherapeutics, the morbidity and mortality of many cancers has decreased significantly. However, compared to oncology in general, the field of neuro-oncology has lagged behind. While new molecularly targeted chemotherapeutics have emerged, the impermeability of the blood–brain barrier (BBB) renders systemic delivery of these clinical agents suboptimal. To circumvent the BBB, novel routes of administration are being applied in the clinic, ranging from intra-arterial infusion and direct infusion into the target tissue (convection enhanced delivery (CED)) to the use of focused ultrasound to temporarily disrupt the BBB. However, the current system depends on a “wait-and-see” approach, whereby drug delivery is deemed successful only when a specific clinical outcome is observed. The shortcomings of this approach are evident, as a failed delivery that needs immediate refinement cannot be observed and corrected. In response to this problem, new theranostic agents, compounds with both imaging and therapeutic potential, are being developed, paving the way for improved and monitored delivery to central nervous system (CNS) malignancies. In this review, we focus on the advances and the challenges to improve early cancer detection, selection of targeted therapy, and evaluation of therapeutic efficacy, brought forth by the development of these new agents.
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Affiliation(s)
- Umberto Tosi
- Department of Neurological Surgery, Weill Cornell Medical College, New York, NY 10065, USA.
| | - Christopher S Marnell
- Department of Neurological Surgery, Weill Cornell Medical College, New York, NY 10065, USA.
| | - Raymond Chang
- Department of Neurological Surgery, Weill Cornell Medical College, New York, NY 10065, USA.
| | - William C Cho
- Department of Clinical Oncology, Queen Elizabeth Hospital, Kowloon, Hong Kong, China.
| | - Richard Ting
- Department of Radiology, Molecular Imaging Innovations Institute, Weill Cornell Medicine, New York, NY 10065, USA.
| | - Uday B Maachani
- Department of Neurological Surgery, Weill Cornell Medical College, New York, NY 10065, USA.
| | - Mark M Souweidane
- Department of Neurological Surgery, Weill Cornell Medical College, New York, NY 10065, USA.
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83
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Payne AH, Hawryluk GW, Anzai Y, Odéen H, Ostlie MA, Reichert EC, Stump AJ, Minoshima S, Cross DJ. Magnetic resonance imaging-guided focused ultrasound to increase localized blood-spinal cord barrier permeability. Neural Regen Res 2017; 12:2045-2049. [PMID: 29323044 PMCID: PMC5784353 DOI: 10.4103/1673-5374.221162] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Spinal cord injury (SCI) affects thousands of people every year in the USA, and most patients are left with some permanent paralysis. Therapeutic options are limited and only modestly affect outcome. To address this issue, we used magnetic resonance imaging-guided focused ultrasound (MRgFUS) as a non-invasive approach to increase permeability in the blood-spinal cord barrier (BSCB). We hypothesize that localized, controlled sonoporation of the BSCB by MRgFUS will aid delivery of therapeutics to the injury. Here, we report our preliminary findings for the ability of MRgFUS to increase BSCB permeability in the thoracic spinal cord of a normal rat model. First, an excised portion of normal rat spinal column was used to characterize the acoustic field and to estimate the insertion losses that could be expected in an MRgFUS blood spinal cord barrier opening. Then, in normal rats, MRgFUS was applied in combination with intravenously administered microbubbles to the spinal cord region. Permeability of the BSCB was indicated as signal enhancement by contrast administered prior to T1-weighted magnetic resonance imaging and verified by Evans blue dye. Neurological testing using the Basso, Beattie, and Breshnahan scale and the ladder walk was normal in 8 of 10 rats tested. Two rats showed minor impairment indicating need for further refinement of parameters. No gross tissue damage was evident by histology. In this study, we have opened successfully the blood spinal cord barrier in the thoracic region of the normal rat spine using magnetic resonance-guided focused ultrasound combined with microbubbles.
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Affiliation(s)
- Allison H Payne
- Department of Radiology and Imaging Sciences, University of Utah, Salt Lake City, UT, USA
| | | | - Yoshimi Anzai
- Department of Radiology and Imaging Sciences, University of Utah, Salt Lake City, UT, USA
| | - Henrik Odéen
- Department of Radiology and Imaging Sciences, University of Utah, Salt Lake City, UT, USA
| | - Megan A Ostlie
- Department of Radiology and Imaging Sciences, University of Utah, Salt Lake City, UT, USA
| | - Ethan C Reichert
- Department of Neurosurgery, University of Utah, Salt Lake City, UT, USA
| | - Amanda J Stump
- Department of Radiology and Imaging Sciences, University of Utah, Salt Lake City, UT, USA
| | - Satoshi Minoshima
- Department of Radiology and Imaging Sciences, University of Utah, Salt Lake City, UT, USA
| | - Donna J Cross
- Department of Radiology and Imaging Sciences, University of Utah, Salt Lake City, UT, USA
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84
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Lelu S, Afadzi M, Berg S, Aslund AKO, Torp SH, Sattler W, de L Davies C. Primary Porcine Brain Endothelial Cells as In Vitro Model to Study Effects of Ultrasound and Microbubbles on Blood-Brain Barrier Function. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2017; 64:281-290. [PMID: 27529871 DOI: 10.1109/tuffc.2016.2597004] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Focused ultrasound (FUS) in the presence of microbubbles transiently and reversibly opens the blood-brain barrier (BBB) in rodents and humans, thereby providing a time window for increased drug delivery into brain tissue. To get insight into the underlying mechanisms that govern ultrasound (US)-mediated opening of the BBB, in vitro models are a useful alternative. In this paper, we have utilized an in vitro BBB model that consists of primary porcine brain endothelial cells (PBECs). PBEC monolayers are grown on permeable membranes, which allow assessment of key features of BBB function as well as US treatment. This experimental model is characterized by low permeability for both small molecules and proteins, has a high transendothelial electrical resistance, and expresses tight junctions and efflux pumps. Here, we compare the effects of inertial and stable cavitation in the presence of SonoVue microbubbles on PBEC monolayers' electrical resistance and permeability properties. Our results point out the fragility of PBEC monolayers, which enhances results variability. In particular, we show that handling of the inserts, such as medium change and transfer to the US setup, modifies the cellular response, and immunostaining of the monolayers introduces damage and cell detachment within the US-exposed monolayers. Our results indicate that stable cavitation might have a more pronounced impact on cell permeability as compared with inertial cavitation in vitro. This paper might contribute to further development of experimental setups that are suitable to characterize the impact of FUS and microbubbles on BBB properties in vitro.
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85
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Ellens NPK, Partanen A. Preclinical MRI-Guided Focused Ultrasound: A Review of Systems and Current Practices. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2017; 64:291-305. [PMID: 27662675 DOI: 10.1109/tuffc.2016.2609238] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Effective preclinical research is a vital component in the development of MRI-guided focused ultrasound (MRgFUS) and its translation to clinic. In this review, we seek to outline the challenges at hand for effective preclinical research, survey different solutions, and underline best practices. Furthermore, we summarize efforts to build and characterize dedicated preclinical MRgFUS equipment, including lab prototypes and available commercial products. Finally, we discuss constraints and considerations specific to using clinical MRgFUS equipment in preclinical research. Specifically, we examine additional hardware that has been used to adapt clinical MRgFUS equipment to better position, constrain, and image preclinical subjects, as well as software solutions that have been used to extend the potential and capabilities of clinical devices.
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86
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Kim HJ, Kim YW, Choi SH, Cho BM, Bandu R, Ahn HS, Kim KP. Triolein Emulsion Infusion Into the Carotid Artery Increases Brain Permeability to Anticancer Agents. Neurosurgery 2016; 78:726-33. [PMID: 26540353 DOI: 10.1227/neu.0000000000001104] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Triolein emulsion infusion into the carotid artery has been reported to induce temporary and reversible opening of the blood-brain barrier by increasing vascular permeability. OBJECTIVE To evaluate the effect of triolein emulsion infusion on brain permeance by anticancer agents. METHODS In the doxorubicin study. 2.4 mg/kg doxorubicin was injected immediately after triolein emulsion (1%, 1.5%, and 2%) infusion into rabbit carotid arteries. Two hours later, bilateral hemispheres and eyeballs were harvested, and doxorubicin concentrations were measured fluorometrically. Doxorubicin ratios of ipsilateral/contralateral hemispheres were compared with those of doxorubicin controls by use of the Kruskal-Wallis test followed by the Dunn test. In the cisplatin study, 10 mg/kg cisplatin was injected immediately after 2% triolein emulsion infusion into rat carotid arteries. Ipsilateral hemispheres were harvested 2, 6, 12, 24, and 36 hours after treatment. Time-dependent cisplatin concentrations were determined by liquid chromatography/electrospray ionization-tandem mass spectrometry/mass spectrometry. RESULTS Doxorubicin concentrations were significantly higher in ipsilateral hemispheres and eyeballs in all 3 triolein treatment groups than in doxorubicin controls. In the cisplatin study, cisplatin concentrations in the ipsilateral hemispheres peaked at 6 hours after infusion of cisplatin. CONCLUSION Brain permeance to anticancer agents was increased by triolein emulsion infusion, which suggests that triolein infusion might be a useful adjuvant treatment for brain tumors.
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Affiliation(s)
- Hak Jin Kim
- *Department of Radiology, College of Medicine, Pusan National University, Biomedical Research Institute, Pusan National University Hospital, Pusan, South Korea;‡Department of Preventive Medicine, College of Medicine, Pusan National University, Yangsan, South Korea;§Department of Applied Chemistry and Institute of Natural Sciences, Kyung Hee University, Yong-in, South Korea
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87
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Crake C, Owen J, Smart S, Coviello C, Coussios CC, Carlisle R, Stride E. Enhancement and Passive Acoustic Mapping of Cavitation from Fluorescently Tagged Magnetic Resonance-Visible Magnetic Microbubbles In Vivo. ULTRASOUND IN MEDICINE & BIOLOGY 2016; 42:3022-3036. [PMID: 27666788 DOI: 10.1016/j.ultrasmedbio.2016.08.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Revised: 07/24/2016] [Accepted: 08/01/2016] [Indexed: 05/05/2023]
Abstract
Previous work has indicated the potential of magnetically functionalized microbubbles to localize and enhance cavitation activity under focused ultrasound exposure in vitro. The aim of this study was to investigate magnetic targeting of microbubbles for promotion of cavitation in vivo. Fluorescently labelled magnetic microbubbles were administered intravenously in a murine xenograft model. Cavitation was induced using a 0.5-MHz focused ultrasound transducer at peak negative focal pressures of 1.2-2.0 MPa and monitored in real-time using B-mode imaging and passive acoustic mapping. Magnetic targeting was found to increase the amplitude of the cavitation signal by approximately 50% compared with untargeted bubbles. Post-exposure magnetic resonance imaging indicated deposition of magnetic nanoparticles in tumours. Magnetic targeting was similarly associated with increased fluorescence intensity in the tumours after the experiments. These results suggest that magnetic targeting could potentially be used to improve delivery of cavitation-mediated therapy and that passive acoustic mapping could be used for real-time monitoring of this process.
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Affiliation(s)
- Calum Crake
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, UK
| | - Joshua Owen
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, UK
| | - Sean Smart
- Gray Institute for Radiation Oncology and Biology, Radiobiology Research Institute, Churchill Hospital, Oxford, UK
| | - Christian Coviello
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, UK
| | - Constantin-C Coussios
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, UK
| | - Robert Carlisle
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, UK
| | - Eleanor Stride
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, UK.
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88
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Su WS, Tsai ML, Huang SL, Liu SH, Yang FY. Controllable permeability of blood-brain barrier and reduced brain injury through low-intensity pulsed ultrasound stimulation. Oncotarget 2016; 6:42290-9. [PMID: 26517350 PMCID: PMC4747225 DOI: 10.18632/oncotarget.5978] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2015] [Accepted: 10/05/2015] [Indexed: 11/25/2022] Open
Abstract
It has been shown that the blood-brain barrier (BBB) can be locally disrupted by focused ultrasound (FUS) in the presence of microbubbles (MB) while sustaining little damage to the brain tissue. Thus, the safety issue associated with FUS-induced BBB disruption (BBBD) needs to be investigated for future clinical applications. This study demonstrated the neuroprotective effects induced by low-intensity pulsed ultrasound (LIPUS) against brain injury in the sonicated brain. Rats subjected to a BBB disruption injury received LIPUS exposure for 5 min after FUS/MB application. Measurements of BBB permeability, brain water content, and histological analysis were then carried out to evaluate the effects of LIPUS. The permeability and time window of FUS-induced BBBD can be effectively modulated with LIPUS. LIPUS also significantly reduced brain edema, neuronal death, and apoptosis in the sonicated brain. Our results show that brain injury in the FUS-induced BBBD model could be ameliorated by LIPUS and that LIPUS may be proposed as a novel treatment modality for controllable release of drugs into the brain.
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Affiliation(s)
- Wei-Shen Su
- Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, Taiwan
| | - Min-Lan Tsai
- Department of Pediatrics, Cheng Hsin General Hospital, Taipei, Taiwan
| | - Sin-Luo Huang
- Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, Taiwan
| | - Shing-Hwa Liu
- Institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Taiwan.,Department of Medical Research, China Medical University Hospital, China Medical University, Taichung, Taiwan
| | - Feng-Yi Yang
- Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, Taiwan.,Biophotonics and Molecular Imaging Research Center, National Yang-Ming University, Taipei, Taiwan.,Biomedical Engineering Research and Development Center, National Yang-Ming University, Taipei, Taiwan
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89
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Focused Ultrasound-Induced Blood-Brain Barrier Opening: Association with Mechanical Index and Cavitation Index Analyzed by Dynamic Contrast-Enhanced Magnetic-Resonance Imaging. Sci Rep 2016; 6:33264. [PMID: 27630037 PMCID: PMC5024096 DOI: 10.1038/srep33264] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2016] [Accepted: 08/22/2016] [Indexed: 01/07/2023] Open
Abstract
Focused ultrasound (FUS) with microbubbles can temporally open the blood-brain barrier (BBB), and the cavitation activities of microbubbles play a key role in the BBB-opening process. Previous attempts used contrast-enhanced magnetic resonance imaging (CE-MRI) to correlate the mechanical index (MI) with the scale of BBB-opening, but MI only partially gauged acoustic activities, and CE-MRI did not fully explore correlations of pharmacodynamic/pharmacokinetic behaviors. Recently, the cavitation index (CI) has been derived to serve as an indicator of microbubble-ultrasound stable cavitation, and may also serve as a valid indicator to gauge the level of FUS-induced BBB opening. This study investigates the feasibility of gauging FUS-induced BBB opened level via the two indexes, MI and CI, through dynamic contrast-enhanced (DCE)-MRI analysis as well as passive cavitation detection (PCD) analysis. Pharmacodynamic/pharmacokinetic parameters derived from DCE-MRI were characterized to identify the scale of FUS-induced BBB opening. Our results demonstrated that DCE-MRI can successfully access pharmacodynamic/pharmacokinetic BBB-opened behavior, and was highly correlated both with MI and CI, implying the feasibility in using these two indices to gauge the scale of FUS-induced BBB opening. The proposed finding may facilitate the design toward using focused ultrasound as a safe and reliable noninvasive CNS drug delivery.
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90
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Unilateral Opening of Rat Blood-Brain Barrier Assisted by Diagnostic Ultrasound Targeted Microbubbles Destruction. BIOMED RESEARCH INTERNATIONAL 2016; 2016:4759750. [PMID: 27579317 PMCID: PMC4989062 DOI: 10.1155/2016/4759750] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Revised: 05/31/2016] [Accepted: 06/08/2016] [Indexed: 12/23/2022]
Abstract
Objective. Blood-brain barrier (BBB) is a key obstacle that prevents the medication from blood to the brain. Microbubble-enhanced cavitation by focused ultrasound can open the BBB and proves to be valuable in the brain drug delivery. The study aimed to explore the feasibility, efficacy, and safety of unilateral opening of BBB using diagnostic ultrasound targeted microbubbles destruction in rats. Methods. A transtemporal bone irradiation of diagnostic ultrasound and intravenous injection of lipid-coated microbubbles were performed at unilateral hemisphere. Pathological changes were monitored. Evans Blue extravasation grades, extraction from brain tissue, and fluorescence optical density were quantified. Lanthanum nitrate was traced by transmission electron microscopy. Results. After diagnostic ultrasound mediated microbubbles destruction, Evans Blue extravasation and fluorescence integrated optical density were significantly higher in the irradiated hemisphere than the contralateral side (all p < 0.01). Erythrocytes extravasations were demonstrated in the ultrasound-exposed hemisphere (4 ± 1, grade 2) while being invisible in the control side. Lanthanum nitrate tracers leaked through interendothelial cleft and spread to the nerve fiber existed in the irradiation side. Conclusions. Transtemporal bone irradiation under DUS mediated microbubble destruction provides us with a more accessible, safer, and higher selective BBB opening approach in rats, which is advantageous in brain targeted drugs delivery.
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91
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Huang Y, Alkins R, Schwartz ML, Hynynen K. Opening the Blood-Brain Barrier with MR Imaging-guided Focused Ultrasound: Preclinical Testing on a Trans-Human Skull Porcine Model. Radiology 2016; 282:123-130. [PMID: 27420647 DOI: 10.1148/radiol.2016152154] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Purpose To develop and test a protocol in preparation for a clinical trial on opening the blood-brain barrier (BBB) with magnetic resonance (MR) imaging-guided focused ultrasound for the delivery of chemotherapy drugs to brain tumors. Materials and Methods The procedures were approved by the institutional animal care committee. A trans-human skull porcine model was designed for the preclinical testing. Wide craniotomies were applied in 11 pigs (weight, approximately 15 kg). A partial human skull was positioned over the animal's brain. A modified clinical MR imaging-guided focused ultrasound brain system was used with a 3.0-T MR unit. The ultrasound beam was steered during sonications over a 3 × 3 grid at 3-mm spacing. Acoustic power levels of 3-20 W were tested. Bolus injections of microbubbles at 4 μL/kg were tested for each sonication. Levels of BBB opening, hemorrhage, and cavitation signal were measured with MR imaging, histologic examination, and cavitation receivers, respectively. A cavitation safety algorithm was developed on the basis of logistic regression of the measurements and tested to minimize the risk of hemorrhage. Results BBB openings of approximately 1 cm3 in volume were visualized with gadolinium-enhanced MR imaging after sonication at an acoustic power of approximately 5 W. Gross examination of histologic specimens helped confirm Evans blue (bound to macromolecule albumin) extravasation, and hematoxylin-eosin staining helped detect only scattered extravasation of red blood cells. In cases where cavitation signals were higher than thresholds, sonications were terminated immediately without causing hemorrhage. Conclusion With a trans-human skull porcine model, this study demonstrated BBB opening with a 230-kHz system in preparation for a clinical trial. © RSNA, 2016 Online supplemental material is available for this article.
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Affiliation(s)
- Yuexi Huang
- From the Department of Physical Sciences, Sunnybrook Research Institute, 2075 Bayview Ave, C713, Toronto, ON, Canada M4N 3M5 (Y.H., R.A., K.H.); Department of Medical Biophysics, University of Toronto, Toronto, Ont, Canada (R.A., K.H.); and Division of Neurosurgery, Sunnybrook Health Sciences Centre, Toronto, Ont, Canada (M.L.S.)
| | - Ryan Alkins
- From the Department of Physical Sciences, Sunnybrook Research Institute, 2075 Bayview Ave, C713, Toronto, ON, Canada M4N 3M5 (Y.H., R.A., K.H.); Department of Medical Biophysics, University of Toronto, Toronto, Ont, Canada (R.A., K.H.); and Division of Neurosurgery, Sunnybrook Health Sciences Centre, Toronto, Ont, Canada (M.L.S.)
| | - Michael L Schwartz
- From the Department of Physical Sciences, Sunnybrook Research Institute, 2075 Bayview Ave, C713, Toronto, ON, Canada M4N 3M5 (Y.H., R.A., K.H.); Department of Medical Biophysics, University of Toronto, Toronto, Ont, Canada (R.A., K.H.); and Division of Neurosurgery, Sunnybrook Health Sciences Centre, Toronto, Ont, Canada (M.L.S.)
| | - Kullervo Hynynen
- From the Department of Physical Sciences, Sunnybrook Research Institute, 2075 Bayview Ave, C713, Toronto, ON, Canada M4N 3M5 (Y.H., R.A., K.H.); Department of Medical Biophysics, University of Toronto, Toronto, Ont, Canada (R.A., K.H.); and Division of Neurosurgery, Sunnybrook Health Sciences Centre, Toronto, Ont, Canada (M.L.S.)
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92
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Horodyckid C, Canney M, Vignot A, Boisgard R, Drier A, Huberfeld G, François C, Prigent A, Santin MD, Adam C, Willer JC, Lafon C, Chapelon JY, Carpentier A. Safe long-term repeated disruption of the blood-brain barrier using an implantable ultrasound device: a multiparametric study in a primate model. J Neurosurg 2016; 126:1351-1361. [PMID: 27285538 DOI: 10.3171/2016.3.jns151635] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE The main limitation to the efficacy of chemotherapy for brain tumors is the restricted access to the brain because of the limited permeability of the blood-brain barrier (BBB). Previous animal studies have shown that the application of pulsed ultrasound (US), in combination with the intravenous injection of microbubbles, can temporarily disrupt the BBB to deliver drugs that normally cannot reach brain tissue. Although many previous studies have been performed with external focused US transducers, the device described in the current work emits US energy using an unfocused transducer implanted in the skull thickness. This method avoids distortion of the US energy by the skull bone and allows for simple, repetitive, and broad disruption of the BBB without the need for MRI monitoring. The purpose of the present study was to determine if the BBB can be safely and repeatedly disrupted using such an implantable unfocused US device in a primate model. METHODS An 11.5-mm-diameter, 1-MHz, planar US device was implanted via a bur hole into the skull of 3 primates (2 Papio anubis [olive] baboons and 1 Macaca fascicularis [macaque]) for 4 months. Pulsed US sonications were applied together with the simultaneous intravenous injection of sulfur hexafluoride microbubbles (SonoVue) every 2 weeks to temporarily disrupt the BBB. In each primate, a total of 7 sonications were performed with a 23.2-msec burst length (25,000 cycles) and a 1-Hz pulse repetition frequency at acoustic pressure levels of 0.6-0.8 MPa. Potential toxicity induced by repeated BBB opening was analyzed using MRI, PET, electroencephalography (EEG), somatosensory evoked potential (SSEP) monitoring, behavioral scales, and histopathological analysis. RESULTS The T1-weighted contrast-enhanced MR images acquired after each sonication exhibited a zone of hypersignal underneath the transducer that persisted for more than 4 hours, indicating a broad region of BBB opening in the acoustic field of the implant. Positron emission tomography images with fluorine-18-labeled fluorodeoxyglucose (FDG) did not indicate any changes in the cerebral metabolism of glucose. Neither epileptic signs nor pathological central nerve conduction was observed on EEG and SSEP recordings, respectively. Behavior in all animals remained normal. Histological analysis showed no hemorrhagic processes, no petechia, and extravasation of only a few erythrocytes. CONCLUSIONS The studies performed confirm that an implantable, 1-MHz US device can be used to repeatedly open the BBB broadly in a large-animal model without inducing any acute, subacute, or chronic lesions.
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Affiliation(s)
- Catherine Horodyckid
- CarThera Research Team, Brain and Spine Institute, Paris;,Departments of 2 Neurosurgery and
| | - Michael Canney
- CarThera Research Team, Brain and Spine Institute, Paris
| | | | | | | | - Gilles Huberfeld
- Paris VI Sorbonne University, School of Medicine, Paris.,INSERM U1129 "Infantile Epilepsies and Brain Plasticity," Paris.,Paris Descartes University, PRES Sorbonne Paris Cité.,CEA, Gif sur Yvette
| | - Chantal François
- Sorbonne Universités, UPMC Univ Paris 06, UMRS 1127, ICM, F-75013 Paris
| | - Annick Prigent
- Inserm U1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMRS 1127, Institut du Cerveau et de la Moelle épinière, ICM, F-75013, Paris
| | - Mathieu D Santin
- Centre de NeuroImagerie de Recherche-CENIR, Paris.,Institut du Cerveau et de la Moelle épinière - ICM, Inserm U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMRS 1127, Paris
| | - Clovis Adam
- Assistance Publique-Hôpitaux de Paris, Bicêtre Hospital, Pathology Department, Le Kremlin-Bicêtre, Paris; and
| | - Jean-Claude Willer
- Physiologie, Assistance Publique-Hôpitaux de Paris, Pitié-Salpêtrière Hospital, Paris.,Paris VI Sorbonne University, School of Medicine, Paris
| | - Cyril Lafon
- INSERM U1032, LabTau, University of Lyon, France
| | | | - Alexandre Carpentier
- Departments of 2 Neurosurgery and.,Paris VI Sorbonne University, School of Medicine, Paris
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93
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Sukovich J, Xu Z, Kim Y, Cao H, Nguyen TS, Pandey A, Hall T, Cain C. Targeted Lesion Generation Through the Skull Without Aberration Correction Using Histotripsy. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2016; 63:671-682. [PMID: 26890732 PMCID: PMC7371448 DOI: 10.1109/tuffc.2016.2531504] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
This study demonstrates the ability of histotripsy to generate targeted lesions through the skullcap without using aberration correction. Histotripsy therapy was delivered using a 500 kHz, 256-element hemispherical transducer with an aperture diameter of 30 cm and a focal distance of 15 cm fabricated in our lab. This transducer is theoretically capable of producing peak rarefactional pressures, based on linear estimation, (p-)LE, in the free field in excess of 200MPa with pulse durations 2 acoustic cycles. Three excised human skullcaps were used displaying attenuations of 73-81% of the acoustic pressure without aberration correction. Through all three skullcaps, compact lesions with radii less than 1mm were generated in red blood cell (RBC) agarose tissue phantoms without aberration correction, using estimated (p-)LE of 28-39MPa, a pulse repetition frequency of 1Hz, and a total number of 300 pulses. Lesion generation was consistently observed at the geometric focus of the transducer as the position of the skullcap with respect to the transducer was varied, and multiple patterned lesions were generated transcranially by mechanically adjusting the position of the skullcap with respect to the transducer to target different regions within. These results show that compact, targeted lesions with sharp boundaries can be generated through intact skullcaps using histotripsy with very short pulses without using aberration correction. Such capability has the potential to greatly simplify transcranial ultrasound therapy for non-invasive transcranial applications, as current ultrasound transcranial therapy techniques all require sophisticated aberration correction.
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94
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Tsai CH, Zhang JW, Liao YY, Liu HL. Real-time monitoring of focused ultrasound blood-brain barrier opening via subharmonic acoustic emission detection: implementation of confocal dual-frequency piezoelectric transducers. Phys Med Biol 2016; 61:2926-46. [PMID: 26988240 DOI: 10.1088/0031-9155/61/7/2926] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Burst-tone focused ultrasound exposure in the presence of microbubbles has been demonstrated to be effective at inducing temporal and local opening of the blood-brain barrier (BBB), which promises significant clinical potential to deliver therapeutic molecules into the central nervous system (CNS). Traditional contrast-enhanced imaging confirmation after focused ultrasound (FUS) exposure serves as a post-operative indicator of the effectiveness of FUS-BBB opening, however, an indicator that can concurrently report the BBB status and BBB-opening effectiveness is required to provide effective feedback to implement this treatment clinically. In this study, we demonstrate the use of subharmonic acoustic emission detection with implementation on a confocal dual-frequency piezoelectric ceramic structure to perform real-time monitoring of FUS-BBB opening. A confocal dual-frequency (0.55 MHz/1.1 MHz) focused ultrasound transducer was designed. The 1.1 MHz spherically-curved ceramic was employed to deliver FUS exposure to induce BBB-opening, whereas the outer-ring 0.55 MHz ceramic was employed to detect the subharmonic acoustic emissions originating from the target position. In stage-1 experiments, we employed spectral analysis and performed an energy spectrum density (ESD) calculation. An optimized 0.55 MHz ESD level change was shown to effectively discriminate the occurrence of BBB-opening. Wideband acoustic emissions received from 0.55 MHz ceramics were also analyzed to evaluate its correlations with erythrocyte extravasations. In stage-2 real-time monitoring experiments, we applied the predetermined ESD change as a detection threshold in PC-controlled algorithm to predict the FUS exposure intra-operatively. In stage-1 experiment, we showed that subharmonic ESD presents distinguishable dynamics between intact BBB and opened BBB, and therefore a threshold ESD change level (5.5 dB) can be identified for BBB-opening prediction. Using this ESD change threshold detection as a surrogate to on/off control the FUS exposure in stage-2 experiments, we demonstrated both excellent sensitivity (92%) and specificity (92.3%) in discriminating BBB-opening occurrence can be obtained in animal treatments, while concurrently achieving a high positive predicted value (95.8%). Wideband ESD was also highly correlated with the occurrence and level of erythrocyte extravasations (r (2) = 0.81). The proposed system configuration and corresponding analysis based on subharmonic acoustic emissions has the potential to be implemented as a real-time feedback control structure for reliable indication of intact FUS-BBB opening for CNS brain drug delivery.
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Affiliation(s)
- Chih-Hung Tsai
- Department of Electrical Engineering, Chang Gung University, Taoyuan, Taiwan
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95
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Poon C, McMahon D, Hynynen K. Noninvasive and targeted delivery of therapeutics to the brain using focused ultrasound. Neuropharmacology 2016; 120:20-37. [PMID: 26907805 DOI: 10.1016/j.neuropharm.2016.02.014] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2015] [Revised: 01/13/2016] [Accepted: 02/15/2016] [Indexed: 11/24/2022]
Abstract
The range of therapeutic treatment options for central nervous system (CNS) diseases is greatly limited by the blood-brain barrier (BBB). While a variety of strategies to circumvent the blood-brain barrier for drug delivery have been investigated, little clinical success has been achieved. Focused ultrasound (FUS) is a unique approach whereby the transcranial application of acoustic energy to targeted brain areas causes a noninvasive, safe, transient, and targeted opening of the BBB, providing an avenue for the delivery of therapeutic agents from the systemic circulation into the brain. There is a great need for viable treatment strategies for CNS diseases, and we believe that the preclinical success of this technique should encourage a rapid movement towards clinical testing. In this review, we address the versatile applications of FUS-mediated BBB opening, the safety profile of the technique, and the physical and biological mechanisms that drive this process. This article is part of the Special Issue entitled "Beyond small molecules for neurological disorders".
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Affiliation(s)
- Charissa Poon
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON, Canada.,Physical Sciences Platform, Sunnybrook Research Institute, Toronto, ON, Canada
| | - Dallan McMahon
- Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada.,Physical Sciences Platform, Sunnybrook Research Institute, Toronto, ON, Canada
| | - Kullervo Hynynen
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON, Canada.,Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada.,Physical Sciences Platform, Sunnybrook Research Institute, Toronto, ON, Canada
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96
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Kobus T, Vykhodtseva N, Pilatou M, Zhang Y, McDannold N. Safety Validation of Repeated Blood-Brain Barrier Disruption Using Focused Ultrasound. ULTRASOUND IN MEDICINE & BIOLOGY 2016; 42:481-92. [PMID: 26617243 PMCID: PMC4816071 DOI: 10.1016/j.ultrasmedbio.2015.10.009] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Revised: 09/29/2015] [Accepted: 10/14/2015] [Indexed: 05/03/2023]
Abstract
The purpose of this study was to investigate the effects on the brain of multiple sessions of blood-brain barrier (BBB) disruption using focused ultrasound (FUS) in combination with micro-bubbles over a range of acoustic exposure levels. Six weekly sessions of FUS, using acoustical pressures between 0.66 and 0.80 MPa, were performed under magnetic resonance guidance. The success and degree of BBB disruption was estimated by signal enhancement of post-contrast T1-weighted imaging of the treated area. Histopathological analysis was performed after the last treatment. The consequences of repeated BBB disruption varied from no indications of vascular damage to signs of micro-hemorrhages, macrophage infiltration, micro-scar formations and cystic cavities. The signal enhancement on the contrast-enhanced T1-weighted imaging had limited value for predicting small-vessel damage. T2-weighted imaging corresponded well with the effects on histopathology and could be used to study treatment effects over time. This study demonstrates that repeated BBB disruption by FUS can be performed with no or limited damage to the brain tissue.
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Affiliation(s)
- Thiele Kobus
- Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA; Department of Radiology and Nuclear Medicine, Radboud University Medical Center, Nijmegen, The Netherlands.
| | - Natalia Vykhodtseva
- Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Magdalini Pilatou
- Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Yongzhi Zhang
- Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Nathan McDannold
- Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
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97
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Hersh DS, Wadajkar AS, Roberts NB, Perez JG, Connolly NP, Frenkel V, Winkles JA, Woodworth GF, Kim AJ. Evolving Drug Delivery Strategies to Overcome the Blood Brain Barrier. Curr Pharm Des 2016; 22:1177-1193. [PMID: 26685681 PMCID: PMC4900538 DOI: 10.2174/1381612822666151221150733] [Citation(s) in RCA: 192] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Accepted: 12/18/2015] [Indexed: 01/10/2023]
Abstract
The blood-brain barrier (BBB) poses a unique challenge for drug delivery to the central nervous system (CNS). The BBB consists of a continuous layer of specialized endothelial cells linked together by tight junctions, pericytes, nonfenestrated basal lamina, and astrocytic foot processes. This complex barrier controls and limits the systemic delivery of therapeutics to the CNS. Several innovative strategies have been explored to enhance the transport of therapeutics across the BBB, each with individual advantages and disadvantages. Ongoing advances in delivery approaches that overcome the BBB are enabling more effective therapies for CNS diseases. In this review, we discuss: (1) the physiological properties of the BBB, (2) conventional strategies to enhance paracellular and transcellular transport through the BBB, (3) emerging concepts to overcome the BBB, and (4) alternative CNS drug delivery strategies that bypass the BBB entirely. Based on these exciting advances, we anticipate that in the near future, drug delivery research efforts will lead to more effective therapeutic interventions for diseases of the CNS.
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Affiliation(s)
| | | | | | | | | | | | | | - Graeme F. Woodworth
- Address correspondence to these authors at the Department of Neurosurgery, University of Maryland School of Medicine, 22 South Greene Street, Baltimore, MD 21201; E-mail: , Departments of Neurosurgery and Pharmaceutical Sciences, University of Maryland, Baltimore, 655 W. Baltimore Street, Baltimore, MD 21201;, E-mail:
| | - Anthony J. Kim
- Address correspondence to these authors at the Department of Neurosurgery, University of Maryland School of Medicine, 22 South Greene Street, Baltimore, MD 21201; E-mail: , Departments of Neurosurgery and Pharmaceutical Sciences, University of Maryland, Baltimore, 655 W. Baltimore Street, Baltimore, MD 21201;, E-mail:
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98
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Suzuki R, Klibanov AL. Co-administration of Microbubbles and Drugs in Ultrasound-Assisted Drug Delivery: Comparison with Drug-Carrying Particles. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 880:205-20. [PMID: 26486340 DOI: 10.1007/978-3-319-22536-4_12] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
There are two alternative approaches to ultrasound-assisted drug delivery. First, the drug can be entrapped into or attached onto the ultrasound-responsive particles and administered in the vasculature, to achieve ultrasound-triggered drug release from the particles and localized tissue deposition in response to ultrasound treatment of the target zone. Second, the drug can be co-administered with the microbubbles or other sonosensitive particles. In this case, the action of ultrasound on the particles (which act as cavitation nuclei) results in the transient improvement of permeability of the physiological barriers, so that the circulating drug can exit the bloodstream and get into the target tissues and cells. We discuss and compare both of these approaches, their characteristic advantages and disadvantages for the specific drug delivery scenarios. Clearly, the system based on the off-label use of the existing approved microbubbles and drugs (or drug carriers) will have a chance of getting to clinical trials faster and with lesser resources spent. However, if a superior curative potential of a sonosensitive drug carrier is proven, and formulation stability problems are addressed properly, this approach may find its way to practical use, especially for nucleic acid delivery scenarios.
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Affiliation(s)
- Ryo Suzuki
- Cardiovascular Division, Robert M Berne Cardiovascular Research Center, University of Virginia, 801394, Charlottesville, VA, 22908, USA.,Department of Drug and Gene Delivery System, Faculty of Pharma-Sciences, Teikyo University, Tokyo, Japan
| | - Alexander L Klibanov
- Cardiovascular Division, Robert M Berne Cardiovascular Research Center, University of Virginia, 801394, Charlottesville, VA, 22908, USA.
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99
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Burgess A, Hynynen K. Microbubble-Assisted Ultrasound for Drug Delivery in the Brain and Central Nervous System. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 880:293-308. [PMID: 26486344 DOI: 10.1007/978-3-319-22536-4_16] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The blood-brain barrier is a serious impediment to the delivery of pharmaceutical treatments for brain diseases, including cancer, neurodegenerative and neuropsychatric diseases. Focused ultrasound, when combined with microbubbles, has emerged as an effective method to transiently and locally open the blood-brain barrier to promote drug delivery to the brain. Focused ultrasound has been used to successfully deliver a wide variety of therapeutic agents to pre-clinical disease models. The requirement for clinical translation of focused ultrasound technology is considered.
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Affiliation(s)
- Alison Burgess
- Physical Sciences, Sunnybrook Research Institute, Toronto, ON, Canada
| | - Kullervo Hynynen
- Physical Sciences, Sunnybrook Research Institute, Toronto, ON, Canada. .,Medical Biophysics, University of Toronto, Toronto, ON, Canada.
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100
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Peng HH, Wu CH, Kang ST, Zhang JW, Liu HL, Chen WS, Wang CH, Yeh CK. Real-time monitoring of inertial cavitation effects of microbubbles by using MRI: In vitro experiments. Magn Reson Med 2015; 77:102-111. [PMID: 26714923 DOI: 10.1002/mrm.26082] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Revised: 11/16/2015] [Accepted: 11/19/2015] [Indexed: 12/23/2022]
Abstract
PURPOSE To investigate the feasibility of half-Fourier acquisition single-shot turbo spin-echo (HASTE) for real-time monitoring of signal changes because of water flow induced by inertial cavitation (IC) during microbubbles (MBs)-present focused ultrasound (FUS) exposure. THEORY AND METHODS Strong turbulence produced in MB solution at the onset of IC results in the difficulty to refocus signal echoes and thus the decrease in signal intensity (SI). Fundamental investigations were conducted using an agar phantom containing MB dilutions exposed to 1.85-MHz FUS. The effects of various experimental conditions including MB concentrations, imaging slice thicknesses, chamber diameters, acoustic pressures, duty cycles, and pulse repetition frequencies (PRFs) were discussed. RESULTS Continuous 2.8 MPa FUS exposure resulted in SI changed from 11% to 55% when MBs concentrations increased from 0.025% to 0.1%. When slice thickness increased from 3 mm to 6 or 8 mm, smaller SI changes were observed (84%, 59%, and 46%). Images acquired with chamber diameter of 6 and 3 mm showed SI changes of 84% and 35%, respectively. In burst modes, higher duty cycles exhibited higher SI changes, and lower PRFs exhibited smaller and longer SI decrease. CONCLUSION Under various conditions, substantial signal changes were observable, suggesting the feasibility of applying HASTE to real-time monitor IC effect under FUS exposure. Magn Reson Med 77:102-111, 2017. © 2015 Wiley Periodicals, Inc.
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Affiliation(s)
- Hsu-Hsia Peng
- Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu, Taiwan
| | - Chen-Hua Wu
- Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu, Taiwan
| | - Shih-Tsung Kang
- Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu, Taiwan
| | - Jia-Wei Zhang
- Department of Electrical Engineering, Chang Gung University, Taoyuan, Taiwan
| | - Hao-Li Liu
- Department of Electrical Engineering, Chang Gung University, Taoyuan, Taiwan
| | - Wen-Shiang Chen
- Department of Physical Medicine and Rehabilitation, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan.,Division of Medical Engineering Research, National Health Research Institutes, Miaoli, Taiwan
| | - Chung-Hsin Wang
- Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu, Taiwan
| | - Chih-Kuang Yeh
- Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu, Taiwan
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