• Chinese Optics Letters
  • Vol. 19, Issue 11, 111701 (2021)
Dengfeng Li, Yachao Zhang, Chao Liu, Jiangbo Chen, Dong Sun*, and Lidai Wang**
Author Affiliations
  • Department of Biomedical Engineering, City University of Hong Kong, Hong Kong 999077, China
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    Microrobots-assisted drug delivery and surgery have been always in the spotlight and are highly anticipated to solve the challenges of cancer in situ treatment. These versatile small biomedical robots are expected to realize direct access to the tumor or disease site for precise treatment, which requires real-time and high-resolution in vivo tracking as feedback for the microrobots’ actuation and control. Among current biomedical imaging methods, photoacoustic imaging (PAI) is presenting its outstanding performances in the tracking of microrobots in the human body derived from its great advantages of excellent imaging resolution and contrast in deep tissue. In this review, we summarize the PAI techniques, imaging systems, and their biomedical applications in microrobots tracking in vitro and in vivo. From a robotic tracking perspective, we also provide some insight into the future of PAI technology in clinical applications.

    1. Introduction

    Scientists have invented microrobots that can directly reach the site of disease to perform medical tasks. Microrobots-assisted in vivo drug delivery, release, and in situ surgery are therefore seen as very promising medical solutions[1]. Microrobots, acting as the carriers, can efficiently deliver drugs for tumor treatment[2], and they can also even culture and transport cells in vivo for tissue engineering[3]. Over the past decades, actuation and control have been the focus of the microrobots’ research[4]. Under the optical[5,6], magnetic[7,8], chemical[9,10], and biological fields[11], microrobots have already been able to achieve a variety of effective movement for in vitro or in vivo environments[12]. In recent years, more researchers are focusing on how microrobots can be truly applied for clinical therapy. Many in vivo experiments on small animals have also been carried out to validate and advance the in vivo application of the microrobots[1316].

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    Dengfeng Li, Yachao Zhang, Chao Liu, Jiangbo Chen, Dong Sun, Lidai Wang. Review of photoacoustic imaging for microrobots tracking in vivo [Invited][J]. Chinese Optics Letters, 2021, 19(11): 111701
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    Category: Biophotonics
    Received: Mar. 30, 2021
    Accepted: May. 14, 2021
    Published Online: Sep. 6, 2021
    The Author Email: Dong Sun (medsun@cityu.edu.hk), Lidai Wang (lidawang@cityu.edu.hk)