Jitter reduction technique for acoustic radiation force impulse microscopy via photoacoustic detection.

Bong Jin Kang,Jin Man Park,Changhan Yoon,Jae Youn Hwang,K Kirk Shung

doi:10.1364/oe.23.019166

Abstract

We demonstrate a jitter noise reduction technique for acoustic radiation force impulse microscopy via photoacoustic detection (PA-ARFI), which promises to be capable of measuring cell mechanics. To reduce the jitter noise induced by Q-switched pulsed laser operated at high repetition frequency, photoacoustic signals from the surface of an ultrasound transducer are aligned by cross-correlation and peak-to-peak detection, respectively. Each method is then employed to measure the displacements of a target sample in an agar phantom and a breast cancer cell due to ARFI application, followed by the quantitative comparison between their performances. The suggested methods for PA-ARFI significantly reduce jitter noises, thus allowing us to measure displacements of a target cell due to ARFI application by less than 3 μm.

Highlights

Various acoustic radiation force impulse (ARFI) imaging techniques have been developed as a non-invasive ultrasonic palpation method for quantitative measurement of elastic properties of tissues [1]
For estimation of the elastic properties of tissues, Acoustic radiation force impulse (ARFI) imaging utilizes short-duration focused acoustic beams to induce localized displacements within the tissues of interest and the displacements are estimated with cross-correlationbased algorithms between echo signals acquired from the regions before and after excitation [2]
This excitation method, utilized for ARFI imaging, typically offers several advantages over other external force excitation methods such as external static compression, external dynamic vibration, or naturally occurring physiologic motion, namely [3]: 1) smaller stresses since the focused acoustic radiation force is directly applied to the region of interest during excitation and 2) only moderate challenges in coupling the excitation to the target tissue [1]

Summary

Introduction

Various acoustic radiation force impulse (ARFI) imaging techniques have been developed as a non-invasive ultrasonic palpation method for quantitative measurement of elastic properties of tissues [1]. For estimation of the elastic properties of tissues, ARFI imaging utilizes short-duration focused acoustic beams to induce localized displacements within the tissues of interest and the displacements are estimated with cross-correlationbased algorithms between echo signals acquired from the regions before and after excitation [2]. This excitation method, utilized for ARFI imaging, typically offers several advantages over other external force excitation methods such as external static compression, external dynamic vibration, or naturally occurring physiologic motion, namely [3]: 1) smaller stresses since the focused acoustic radiation force is directly applied to the region of interest during excitation and 2) only moderate challenges in coupling the excitation to the target tissue [1]. The ARFI imaging techniques allowed distinguishing in vivo a cyst from solid lesions in the breast [12] as well as a reactive lymph node from a breast mass [9] by estimating the viscoelastic properties of target regions

Methods

Results

Conclusion