The field of medical ultrasound has undergone a significant evolution since the development of microbubbles as contrast agents. However, because of their size, microbubbles remain in the vasculature and therefore have limited clinical applications. Building a better—and smaller—bubble can expand the applications of contrast-enhanced ultrasound by allowing bubbles to extravasate from blood vessels—creating new opportunities. In this review, we summarize recent research on the formulation and use of nanobubbles (NBs) as imaging agents and as therapeutic vehicles. We discuss the ongoing debates in the field and reluctance to accepting NBs as an acoustically active construct and a potentially impactful clinical tool that can help shape the future of medical ultrasound. We hope that the overview of key experimental and theoretical findings in the NB field presented in this article provides a fundamental framework that will help clarify NB–ultrasound interactions and inspire engagement in the field.

自从微泡作为造影剂的发展以来，医学超声领域经历了重大发展。然而，由于其尺寸，微泡保留在脉管系统中，因此临床应用受到限制。构建更好、更小的气泡可以通过允许气泡从血管中溢出来扩展对比增强超声的应用，从而创造新的机会。在这篇综述中，我们总结了纳米气泡（NB）作为显像剂和治疗载体的配方和用途的最新研究。我们讨论了该领域正在进行的争论，以及不愿接受 NB 作为声学活性结构和可能有影响力的临床工具，以帮助塑造医学超声的未来。我们希望本文对 NB 领域关键实验和理论发现的概述提供了一个基本框架，有助于阐明 NB 与超声的相互作用并激发对该领域的参与。