Acoustic Radiation Force: A Review of Four Mechanisms for Biomedical Applications

Abstract

Radiation force is a universal phenomenon in any wave motion where the wave energy produces a static or transient force on the propagation medium. The theory of acoustic radiation force (ARF) dates back to the early 19th century. In recent years, there has been an increasing interest in the biomedical applications of ARF. Following a brief history of acoustic radiation force, this paper describes a concise theory of ARF under four physical mechanisms of radiation force generation in tissue-like media. These mechanisms are primarily based on the dissipation of acoustic energy of propagating waves, the reflection of the incident wave, gradients of the compressional wave speeds, and the spatial variations of energy density in standing acoustic waves.Examples describing some of the practical applications of ARF under each mechanism are presented. This paper concludes with a discussion on selected ideas for potential future applications of ARF in biomedicine.

Constrained Volume Micro- and Nanoparticle Collection Methods in Microfluidic Systems

“…The principle behind the acoustic radiation force is that an acoustic wave traveling through a particle-containing medium can impart its energy into the particles due to differing acoustic properties between the particles and the medium [ 129 ]. This is similar to light diffracting and imparting momentum when traveling between materials of differing refractive indices.…”

Feasibility of nondestructive testing using transient vibrations excited by acoustic radiation force

“…It is induced by sound waves incident on the boundary and is proportional to the square of the sound pressure amplitude. 9,34) A dynamic acoustic radiation force is generated according to its envelope for amplitudemodulated ultrasound. 14) In VA, the vibrations of an object generated by the radiation force caused by sound waves are observed.…”

“…This force is used for various applications. 9) Vibro-acoustography (VA), 10,11) applied in this study, is a non-contact measurement and imaging method that uses the vibrations of an object excited by the acoustic radiation force. Local vibrations at any point in an object can be excited by the acoustic radiation force with a frequency equal to twice the modulation frequency of focusing amplitude-modulated ultrasound.…”

2D acoustofluidic distributions in micro-chambers modulated by Sierpiński-type structural plates

“…In general, acoustofluidics aims to exploit acoustic radiation force and acoustic streaming-induced drag force in microfluidic systems for bio-sample or particle manipulation [13][14][15]. The acoustic radiation force commonly originates from the synergistic effect of ultrasound field with manipulated objects when there are acoustic property differences among target particles and surrounding media [16,17], while the acoustic streaming field is a kind of time-independent flow and predominantly generated by sound energy dissipation of high-frequency acoustic oscillations in viscous fluid media [18,19]. In comparison with the existing passive microfluidic methods with high-throughput characteristics (particle filtration [20], inertial movement [21], and hydraulic driving [22]) and the achievable active manipulation manners with high-precision advantages (mechanical [23], electric/dielectric [24], magnetic/diamagnetic [25], and optical effects [26]), acoustic manipulation methods are commonly considered to have inherent merits like low power consumption, little physiological damage to controlled bio-organisms (biocompatibility) [27], non-invasive and non-contact manipulation processes [28], independence of photoelectromagnetic properties [29], customer-friendly operation characteristics [30], and so forth.…”