Nanodroplet-Based Super-Resolution Ultrasound Localization Microscopy

Over the past decade, super-resolution ultrasound localizationmicroscopy (SR-ULM) has revolutionized ultrasound imaging with itscapability to resolve the microvascular structures below the ultrasounddiffraction limit. The introduction of this imaging technique enablesthe visualization, quantification, and characterization of tissuemicrovasculature. The early implementations of SR-ULM utilize microbubbles(MBs) that require a long image acquisition time due to the requirementof capturing sparsely isolated microbubble signals. The next-generationSR-ULM employs nanodroplets that have the potential to significantlyreduce the image acquisition time without sacrificing the resolution.This review discusses various nanodroplet-based ultrasound localizationmicroscopy techniques and their corresponding imaging mechanisms.A summary is given on the preclinical applications of SR-ULM withnanodroplets, and the challenges in the clinical translation of nanodroplet-basedSR-ULM are presented while discussing the future perspectives. Inconclusion, ultrasound localization microscopy is a promising microvasculatureimaging technology that can provide new diagnostic and prognosticinformation for a wide range of pathologies, such as cancer, heartconditions, and autoimmune diseases, and enable personalized treatmentmonitoring at a microlevel.

Automated summary

Super-resolution ultrasound localization microscopy (SR-ULM) has revolutionized ultrasound imaging by resolving microvascular structures below the diffraction limit. This review discusses nanodroplet-based SR-ULM techniques, their imaging mechanisms, preclinical applications, and challenges in clinical translation. SR-ULM is a promising technology for microvasculature imaging that can provide valuable diagnostic and prognostic information for various pathologies and enable personalized treatment monitoring.