Versatile Ultrasound-Compatible Microfluidic Platform for In Vitro Microvasculature Flow Research and Imaging...

Area of Science:

• Biomedical Engineering
• Medical Imaging
• Microfluidics

Background:

• Ultrasound localization microscopy (ULM) offers super-resolution imaging and velocity mapping of microvasculature using microbubble contrast agents.
• Developing ultrasound-compatible microvasculature phantoms is crucial for controlled studies of microbubble behavior in ULM.
• Existing phantom technologies present limitations in replicating complex vascular structures and flow dynamics.

Purpose of the Study:

• To introduce a novel class of gelatin-based microfluidic-inspired phantoms for Ultrasound Localization Microscopy (ULM).
• To investigate microbubble behavior, flow dynamics, and imaging acquisition times within complex vascular networks created using these phantoms.
• To demonstrate the capability of these phantoms in replicating intricate vascular geometries, including bifurcating and converging vessels.

Main Methods:

• Fabrication of gelatin-based microfluidic phantoms with channel diameters as small as 100 μm.
• Utilizing Ultrasound Localization Microscopy (ULM) to track microbubble contrast agents within the phantoms.
• Systematically varying bifurcation angles and flow rates to assess their impact on microbubble distribution and imaging acquisition times.

Main Results:

• Demonstrated successful creation of complex, reproducible microvascular networks with channel diameters down to 100 μm.
• Observed significantly longer acquisition times in narrower vessels (e.g., 72% increase for 100 μm branching from 300 μm).
• Successfully fabricated trifurcating and converging microfluidic phantoms, showcasing the method's versatility beyond traditional capabilities.

Conclusions:

• The developed gelatin-based phantoms provide a versatile platform for in vitro microvasculature research using ULM.
• These phantoms facilitate noninvasive studies of complex flow patterns and enable optimization of ultrasound imaging techniques.
• This advancement supports the investigation of microbubble dynamics in controlled, complex vascular environments, advancing microvascular research.