scholarly journals BOT-01 BLOOD-BRAIN BARRIER OPENING USING 220-KHZ TRANSCRANIAL MRI-GUIDED FOCUSED ULTRASOUND AND MICROBUBBLES IN MOUSE AND RAT

2019 ◽  
Vol 1 (Supplement_2) ◽  
pp. ii12-ii12
Author(s):  
Michiharu Yoshida ◽  
Kazuo Maruyama ◽  
Yasutaka Kato ◽  
Rachmilevitch Itay ◽  
Syuji Suzuki ◽  
...  

Abstract OBJECTIVE In neuro-oncology, it is believed that one major obstacle to effective chemotherapy is the high vascularity and heterogenous permeability of brain tumors. Focused ultrasound (FUS) exposure with the microbubbles has been shown to transiently open the blood-brain barrier (BBB) without depositing thermal energy, and thus may enhance the delivery of various therapeutic drugs into brain tumors. The aim of this study was to evaluate the BBB opening using 220-kHz transcranial MRI-guided FUS (TcMRgFUS) device and microbubbles in mouse and rat. METHODS The experiments were performed with the 220-kHz ExAblate Neuro TcMRgFUS system (InSightec) and novel lipid bubbles (LB, Teikyo Univ.). Normal mouse and rat brains were irradiated with TcMRgFUS (output power, 5W; duration of irradiation, 30 s; duty cycle 100%) following intravenous injection of 6x107 LB per mouse and rat, respectively. On irradiation, target temperature rise & cavitation signal were monitored by MR thermometry and cavitation receiver, respectively. Immediately after irradiation, BBB opening and complications were detected based on T1, T2, T2*, and Gadolinium (Gd) enhanced T1-weighted images. RESULTS The maximum temperature of brain tissue was under 42 C. There were no risky-cavitation signals causing hemorrhage. The FUS-LB exposure induced successful BBB opening effect in both mouse and rat, confirmed by Gd enhancement in the target region, lateral ventricles, and sulcus. In addition, there were no complications such as edema, coagulation, and hemorrhage. CONCLUSIONS Although there remain many conditions to be optimized, BBB opening using a 220-kHz TcMRgFUS device and LB can offer a non-invasive and feasible drug delivery for brain malignancies.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Antonios N. Pouliopoulos ◽  
Nancy Kwon ◽  
Greg Jensen ◽  
Anna Meaney ◽  
Yusuke Niimi ◽  
...  

AbstractAn emerging approach with potential in improving the treatment of neurodegenerative diseases and brain tumors is the use of focused ultrasound (FUS) to bypass the blood–brain barrier (BBB) in a non-invasive and localized manner. A large body of pre-clinical work has paved the way for the gradual clinical implementation of FUS-induced BBB opening. Even though the safety profile of FUS treatments in rodents has been extensively studied, the histological and behavioral effects of clinically relevant BBB opening in large animals are relatively understudied. Here, we examine the histological and behavioral safety profile following localized BBB opening in non-human primates (NHPs), using a neuronavigation-guided clinical system prototype. We show that FUS treatment triggers a short-lived immune response within the targeted region without exacerbating the touch accuracy or reaction time in visual-motor cognitive tasks. Our experiments were designed using a multiple-case-study approach, in order to maximize the acquired data and support translation of the FUS system into human studies. Four NHPs underwent a single session of FUS-mediated BBB opening in the prefrontal cortex. Two NHPs were treated bilaterally at different pressures, sacrificed on day 2 and 18 post-FUS, respectively, and their brains were histologically processed. In separate experiments, two NHPs that were earlier trained in a behavioral task were exposed to FUS unilaterally, and their performance was tracked for at least 3 weeks after BBB opening. An increased microglia density around blood vessels was detected on day 2, but was resolved by day 18. We also detected signs of enhanced immature neuron presence within areas that underwent BBB opening, compared to regions with an intact BBB, confirming previous rodent studies. Logistic regression analysis showed that the NHP cognitive performance did not deteriorate following BBB opening. These preliminary results demonstrate that neuronavigation-guided FUS with a single-element transducer is a non-invasive method capable of reversibly opening the BBB, without substantial histological or behavioral impact in an animal model closely resembling humans. Future work should confirm the observations of this multiple-case-study work across animals, species and tasks.


2014 ◽  
Vol 189 ◽  
pp. 123-132 ◽  
Author(s):  
Elizabeth Nance ◽  
Kelsie Timbie ◽  
G. Wilson Miller ◽  
Ji Song ◽  
Cameron Louttit ◽  
...  

2021 ◽  
Vol 118 (37) ◽  
pp. e2103280118
Author(s):  
Pavlos Anastasiadis ◽  
Dheeraj Gandhi ◽  
Yutong Guo ◽  
Abdul-Kareem Ahmed ◽  
Soren M. Bentzen ◽  
...  

Pharmacological treatment of gliomas and other brain-infiltrating tumors remains challenging due to limited delivery of most therapeutics across the blood–brain barrier (BBB). Transcranial MRI-guided focused ultrasound (FUS), an emerging technology for noninvasive brain treatments, enables transient opening of the BBB through acoustic activation of circulating microbubbles. Here, we evaluate the safety and utility of transcranial microbubble-enhanced FUS (MB-FUS) for spatially targeted BBB opening in patients with infiltrating gliomas. In this Phase 0 clinical trial (NCT03322813), we conducted comparative and quantitative analyses of FUS exposures (sonications) and their effects on gliomas using MRI, histopathology, microbubble acoustic emissions (harmonic dose [HD]), and fluorescence-guided surgery metrics. Contrast-enhanced MRI and histopathology indicated safe and reproducible BBB opening in all patients. These observations occurred using a power cycling closed feedback loop controller, with the power varying by nearly an order of magnitude on average. This range underscores the need for monitoring and titrating the exposure on a patient-by-patient basis. We found a positive correlation between microbubble acoustic emissions (HD) and MR-evident BBB opening (P = 0.07) and associated interstitial changes (P < 0.01), demonstrating the unique capability to titrate the MB-FUS effects in gliomas. Importantly, we identified a 2.2-fold increase of fluorescein accumulation in MB-FUS–treated compared to untreated nonenhancing tumor tissues (P < 0.01) while accounting for vascular density. Collectively, this study demonstrates the capabilities of MB-FUS for safe, localized, controlled BBB opening and highlights the potential of this technology to improve the surgical and pharmacologic treatment of brain tumors.


2018 ◽  
Author(s):  
C. Constans ◽  
H. Ahnine ◽  
M. D. Santin ◽  
S. Lehericy ◽  
M. Tanter ◽  
...  

AbstractWe demonstrate the feasibility of non-invasively modulating the visual cortex activity of non-human primates by local ultrasound-induced delivery of an inhibitory neurotransmitter (GABA). GABA was injected intravenously after the blood brain barrier (BBB) was transiently disrupted with focused ultrasound (FUS) coupled with ultrasound contrast agents (UCA). Visual evoked potentials exhibited a significant and progressive decrease of the activity. Combined effects of neuromodulation and BBB opening were shown to be 8.7 times less important than GABA-induced inhibition. During the sonication, the UCA harmonic response was monitored to estimate the level of stable cavitation (signature of BBB opening efficiency) and to avoid damages due to inertial cavitation (automatic shutdown of the sonication when detected). As recent developments in beam forming have shown that ultrasound beams can be focused non-invasively in deep-seated human brain locations, our results hold promise to explore and treat the brain with a non-invasive, controllable, repeatable and reversible method.


2021 ◽  
Vol 10 (1) ◽  
Author(s):  
So Hee Park ◽  
Kyoungwon Baik ◽  
Seun Jeon ◽  
Won Seok Chang ◽  
Byoung Seok Ye ◽  
...  

Abstract Background Focused ultrasound (FUS)-mediated blood–brain barrier (BBB) opening has shown efficacy in removal of amyloid plaque and improvement of cognitive functions in preclinical studies, but this is rarely reported in clinical studies. This study was conducted to evaluate the safety, feasibility and potential benefits of repeated extensive BBB opening. Methods In this open-label, prospective study, six patients with Alzheimer’s disease (AD) were enrolled at Severance Hospital in Korea between August 2020 and September 2020. Five of them completed the study. FUS-mediated BBB opening, targeting the bilateral frontal lobe regions over 20 cm3, was performed twice at three-month intervals. Magnetic resonance imaging, 18F-Florbetaben (FBB) positron emission tomography, Caregiver-Administered Neuropsychiatric Inventory (CGA-NPI) and comprehensive neuropsychological tests were performed before and after the procedures. Results FUS targeted a mean volume of 21.1 ± 2.7 cm3 and BBB opening was confirmed at 95.7% ± 9.4% of the targeted volume. The frontal-to-other cortical region FBB standardized uptake value ratio at 3 months after the procedure showed a slight decrease, which was statistically significant, compared to the pre-procedure value (− 1.6%, 0.986 vs1.002, P = 0.043). The CGA-NPI score at 2 weeks after the second procedure significantly decreased compared to baseline (2.2 ± 3.0 vs 8.6 ± 6.0, P = 0.042), but recovered after 3 months (5.2 ± 5.8 vs 8.6 ± 6.0, P = 0.89). No adverse effects were observed. Conclusions The repeated and extensive BBB opening in the frontal lobe is safe and feasible for patients with AD. In addition, the BBB opening is potentially beneficial for amyloid removal in AD patients.


2013 ◽  
Vol 39 (5) ◽  
pp. S26
Author(s):  
W. Feng ◽  
S. Yu ◽  
L. Lin ◽  
L. Li ◽  
C. Youli ◽  
...  

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Agessandro Abrahao ◽  
Ying Meng ◽  
Maheleth Llinas ◽  
Yuexi Huang ◽  
Clement Hamani ◽  
...  

Abstract MR-guided focused ultrasound (MRgFUS) is an emerging technology that can accurately and transiently permeabilize the blood-brain barrier (BBB) for targeted drug delivery to the central nervous system. We conducted a single-arm, first-in-human trial to investigate the safety and feasibility of MRgFUS-induced BBB opening in eloquent primary motor cortex in four volunteers with amyotrophic lateral sclerosis (ALS). Here, we show successful BBB opening using MRgFUS as demonstrated by gadolinium leakage at the target site immediately after sonication in all subjects, which normalized 24 hours later. The procedure was well-tolerated with no serious clinical, radiologic or electroencephalographic adverse events. This study demonstrates that non-invasive BBB permeabilization over the motor cortex using MRgFUS is safe, feasible, and reversible in ALS subjects. In future, MRgFUS can be coupled with promising therapeutics providing a targeted delivery platform in ALS.


2014 ◽  
Vol 34 (7) ◽  
pp. 1197-1204 ◽  
Author(s):  
Hong Chen ◽  
Elisa E Konofagou

Focused ultrasound (FUS) in combination with microbubbles (MBs) has been successfully used in the delivery of various-size therapeutic agents across the blood–brain barrier (BBB). This study revealed that FUS-induced BBB opening size, defined by the size of the largest molecule that can permeate through the BBB, can be controlled by the acoustic pressure as dictated by cavitational mechanisms. Focused ultrasound was applied onto the mouse hippocampus in the presence of systemically administered MBs for trans-BBB delivery of fluorescently labeled dextrans with molecular weights 3 to 2,000 kDa (hydrodynamic diameter: 2.3 to 54.4 nm). The dextran delivery outcomes were evaluated using ex vivo fluorescence imaging. Cavitation detection was employed to monitor the MB cavitation activity associated with the delivery of these agents. It was found that the BBB opening size was smaller than 3 kDa (2.3 nm) at 0.31 MPa, up to 70 kDa (10.2 nm) at 0.51 MPa, and up to 2,000 kDa (54.4 nm) at 0.84 MPa. Relatively smaller opening size (up to 70 kDa) was achieved with stable cavitation only; however, inertial cavitation was associated with relatively larger BBB opening size (above 500 kDa). These findings indicate that the BBB opening size can be controlled by the acoustic pressure and predicted using cavitation detection.


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