Subcellular spatial resolution achieved for deep-brain imaging in vivo using a minimally invasive multimode fiber

Area of Science:

• Neuroscience
• Optical Imaging
• Biomedical Engineering

Background:

• Understanding the mammalian central nervous system requires high-resolution imaging of deep-brain structures.
• Current methods face challenges in balancing imaging resolution with tissue damage.
• Advances in wavefront shaping and computational power enable novel high-resolution imaging techniques.

Purpose of the Study:

• To develop a compact and optimized approach for minimally invasive in vivo brain imaging.
• To achieve diffraction-limited spatial resolution in deep-brain imaging applications.
• To reduce tissue lesion volume significantly while maintaining imaging performance.

Main Methods:

• Utilized wavefront control of light propagation through a single 50-microm-core multimode optical fiber (MMF).
• Implemented a novel approach for deterministic light propagation through optically complex media.
• Developed a minimally invasive technique for in vivo applications.

Main Results:

• Demonstrated high-resolution fluorescence imaging of subcellular neuronal structures (dendrites, synaptic specializations) in deep-brain regions of living mice.
• Achieved a reduction in tissue lesion volume by more than 100-fold.
• Successfully monitored stimulus-driven functional calcium (Ca2+) responses in vivo.
• Preserved diffraction-limited imaging performance.

Conclusions:

• This approach represents a major breakthrough in deep-brain imaging, significantly reducing tissue damage.
• It heralds new possibilities for in vivo investigation of the mammalian central nervous system.
• The technique offers high-resolution imaging capabilities with minimal invasiveness.