Fast and selective super-resolution ultrasound in vivo with sono-switchable nanodroplets

Kai Riemer; Matthieu Toulemonde; Jipeng Yan; Marcelo Lerendegui; Eleanor Stride; Peter D. Weinberg; Christopher Dunsby; Meng-Xing Tang

doi:10.1109/tmi.2022.3223554

arXiv · 2203.04263

Fast and selective super-resolution ultrasound in vivo with sono-switchable nanodroplets

Kai Riemer·Matthieu Toulemonde·Jipeng Yan·Marcelo Lerendegui·Eleanor Stride·Peter D. Weinberg·Christopher Dunsby·Meng-Xing Tang

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Abstract

Perfusion by the microcirculation is key to the development, maintenance and pathology of tissue. Its measurement with high spatiotemporal resolution is consequently valuable but remains a challenge in deep tissue. Ultrasound Localization Microscopy (ULM) provides very high spatiotemporal resolution but the use of microbubbles requires low contrast agent concentrations, a long acquisition time, and gives little control over the spatial and temporal distribution of the bubbles. The present study is the first to demonstrate Acoustic Wave Sparsely-Activated Localization Microscopy (AWSALM) and fast-AWSALM for in vivo super-resolution ultrasound imaging, offering contrast on demand and vascular selectivity. Three different formulations of sono-switchable contrast agents were tested. We demonstrate their use with ultrasound mechanical indices well within recommended safety limits to enable fast on-demand sparse switching at very high agent concentrations. We produce super-localization maps of the rabbit renal vasculature with acquisition times between 5.5 s and 0.25 s, and an 4-fold improvement in spatial resolution. We present the unique selectivity of AWSALM in visualizing specific vascular branches and downstream microvasculature, and we show super-localized kidney structures in systole and diastole with fast-AWSALM. In conclusion we demonstrate the feasibility of fast and selective measurement of microvascular dynamics in vivo with subwavelength resolution using ultrasound and sono-switchable nanodroplets.

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BibTeX RIS

Kai Riemer, Matthieu Toulemonde, Jipeng Yan, Marcelo Lerendegui, Eleanor Stride, Peter D. Weinberg, Christopher Dunsby, Meng-Xing Tang. 2022-03-08. Fast and selective super-resolution ultrasound in vivo with sono-switchable nanodroplets. https://doi.org/10.1109/tmi.2022.3223554

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