Ultrasound Safety with Midfrequency Transcranial Sonothrombolysis: Preliminary Study on Normal Macaca Monkey Brain

Shimizu, Jun; Fukuda, Takahiro; Abe, Toshiaki; Ogihara, Makoto; Kubota, Jun; Sasaki, Akira; Azuma, Takashi; Sasaki, Kohsuke; Shimizu, Keiko; Oishi, Takao; Umemura, Shin Ichiro; Furuhata, Hiroshi

doi:10.1016/j.ultrasmedbio.2012.02.009

Cited by 21 publications

(23 citation statements)

References 28 publications

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“…A dual-frequency array capable of performing 2.5-MHz TCCS and emitting a 500-kHz sonothrombolysis beam was developed for transcranial insonation (Azuma et al 2010). The transcranial ultrasound field produced by this device was evaluated in-vitro and the safety of this approach was demonstrated in a healthy primate model (Shimizu et al 2012). Bouchoux et al (2014) simulated 120 and 500-kHz transcranial ultrasound fields from the head CT scans of 20 ischemic stroke patients using a validated acoustic propagation numerical model (Bouchoux et al 2012).…”

Section: 2 Mechanisms Of Thrombolytic Enhancementmentioning

confidence: 99%

“…Small animal models, such as rodent (Daffertshofer et al 2004) and rabbit (Hölscher et al 2012), are used in sonothrombolysis due to their low cost, ease of handling, and accumulation of data from previous studies. Large animal models, such as swine (Culp 2004) and primates (Shimizu et al 2012), are needed to model the propagation of ultrasound through the skull and brain architecture. Thrombus formation can be initiated by incubation of autologous blood within a stenotic artery (Culp 2004; Damianou et al 2014).…”

Section: 3 Experimental Evidence For Ultrasound-enhanced Efficacymentioning

confidence: 99%

See 1 more Smart Citation

Sonothrombolysis

Bader¹,

Bouchoux²,

Holland³

2016

Advances in Experimental Medicine and Biology

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Thrombo-occlusive disease is a leading cause of morbidity and mortality. In this chapter, the use of ultrasound to accelerate clot breakdown alone or in combination with thrombolytic drugs will be reported. Primary thrombus formation during cardiovascular disease and standard treatment methods will be discussed. Mechanisms for ultrasound enhancement of thrombolysis, including thermal heating, radiation force, and cavitation, will be reviewed. Finally, in-vitro, in-vivo and clinical evidence of enhanced thrombolytic efficacy with ultrasound will be presented and discussed.

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Section: 2 Mechanisms Of Thrombolytic Enhancementmentioning

confidence: 99%

Section: 3 Experimental Evidence For Ultrasound-enhanced Efficacymentioning

confidence: 99%

Sonothrombolysis

Bader¹,

Bouchoux²,

Holland³

2016

Advances in Experimental Medicine and Biology

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“…In this sense, ultrasound safety is actually a dose control issue [12][13][14][15]. Some authors found that at 1.2 W/cm 2 , ultrasonic sound exposure can lead to open of the blood-brain barrier [21].…”

Section: Discussionmentioning

confidence: 99%

“…Currently, studies on ultrasound caused tissue injury focus on aspects of therapeutic ultrasound or TCD and the observations include pathological changes in tissue, thermal effects and impact of ultrasound on the blood-brain barrier caused [12][13][14][15][16][17][18][19][20]. In our previous http://dx.doi.org/10.1016/j.clineuro.2015.01.011 0303-8467/© 2015 Elsevier B.V. All rights reserved.…”

Section: Introductionmentioning

confidence: 99%

Safety of thrombolytic therapy with rt-PA and transcranial color Doppler ultrasound (TCCS) combined with microbubbles: A histopathologic study on rabbit brain tissues

Ren

Wang

et al. 2015

Clinical Neurology and Neurosurgery

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“…Because of the risk of cerebral hemorrhage [2], a transcranial ultrasonic treatment device that uses a frequency $500 kHz is under development [3,4] to lower mechanical and thermal risks. Development of such a device requires knowledge of the transmissivity of ultrasound through the temporal bone, which is a thin part of the human skull ($a few millimeters thick).…”

mentioning

confidence: 99%

Reduction of ultrasound transmissivity through a bone-phantom plate resulting from shear wave excitation

Saito

2014

Acoust. Sci. & Tech.

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The results of clinical trials have suggested that ultrasound irradiation can enhance the effectiveness of thrombolytic agents and increase the recanalization rate for acute ischemic stroke patients [1]. Because of the risk of cerebral hemorrhage [2], a transcranial ultrasonic treatment device that uses a frequency $500 kHz is under development [3,4] to lower mechanical and thermal risks. Development of such a device requires knowledge of the transmissivity of ultrasound through the temporal bone, which is a thin part of the human skull ($a few millimeters thick). To clarify the transmissivity dependence on bone thickness, we experimentally measured transmissivity through a bone-phantom plate in water (which has acoustic properties similar to those of soft tissue). Although our experimental results were almost consistent with those of a model calculation based on normal incident plane waves, we discerned a definitive discrepancy between them. In this Short Note, we report on a process for pursuing the cause of this discrepancy.In the case of normal incidence of a plane wave to a bonephantom plate in water, the energy transmissivity is given by the formulawhere k b is the wave number in the bone-phantom plate, d is the thickness of the bone-phantom plate, Z w is the acoustic impedance of water, and Z b is the acoustic impedance of the bone-phantom plate (for the derivation, see, for example, [5]). The effect of absorption by the bone-phantom plate was taken into account by the substitution k b ! k b À i f , where is the absorption coefficient and f is the frequency. Figure 1 shows the transmissivity calculated by using the above formula as a function of bone-phantom plate thickness. There is a peak around 3 mm, which corresponds to half the wavelength of a 500 kHz wave in the bone-phantom plate.In our experiment, we used 20 bone-phantom plates (of sound speed = 2,884 m/s, density = 1,664 kg/m 3 , and absorption coefficient = 46.3 Np/m/MHz), ranging from 0.6 to 4.4 mm by 0.2 mm steps. Almost all Japanese temporal bones are considered to be within this range. The plates were special order products, and the acoustic parameters were measured by the manufacture. The parameters of the plate were similar to those of human skull [6]. A transducer, whose surface is a disk of 24 mm in diameter, was located 12 mm from the bonephantom plate in a water-filled tank. Ultrasound entered the bone-phantom plate almost normally. The transmitted wave was measured by a needle-type hydrophone (Onda Corporation, Sunnyvale, CA, USA) at a position 60 mm away from the transducer surface on the central axis of the disk. Figure 2(a) shows the experimental result. There is a peak around 3 mm, as expected. Equation (1) can explain the overall tendency. However, we found a dip at 3.2 mm, which is not expected by using Eq. (1).We repeated the experiment several times, and the 3.2 mm dip appeared each time. We investigated the reason for this reproducible 3.2 mm dip. At first, we suspected the quality of the material; one 3.2 mm plate might diff...

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Ultrasound Safety with Midfrequency Transcranial Sonothrombolysis: Preliminary Study on Normal Macaca Monkey Brain

Cited by 21 publications

References 28 publications

Sonothrombolysis

Sonothrombolysis

Safety of thrombolytic therapy with rt-PA and transcranial color Doppler ultrasound (TCCS) combined with microbubbles: A histopathologic study on rabbit brain tissues

Reduction of ultrasound transmissivity through a bone-phantom plate resulting from shear wave excitation

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