Nonlinear sound-sheet microscopy: imaging opaque organs at the capillary and cellular scale.

Area of Science:

• Biomedical imaging
• Acoustic microscopy
• Biophysics

Background:

• Light-sheet fluorescence microscopy visualizes dynamic cellular processes but is limited by light scattering and photobleaching in thick tissues.
• Current limitations restrict advanced 3D imaging to thin or translucent biological specimens.

Purpose of the Study:

• To develop a novel imaging technique overcoming the limitations of light-sheet microscopy for thick tissue applications.
• To enable fast and volumetric imaging of targeted biological functions in cm³ scale tissues.

Main Methods:

• Utilized non-diffractive ultrasonic beams with cross-amplitude modulation and nonlinear acoustic reporters.
• Employed genetically encoded gas vesicles for volumetric tumor gene expression imaging.
• Applied intravascular microbubble contrast agents for localization microscopy of cerebral capillaries.

Main Results:

• Achieved volumetric imaging of tumor gene expression at the cm³ scale.
• Enabled localization microscopy of previously uncharted cerebral capillary networks.
• Demonstrated nonlinear sound-sheet microscopy with ~64x speed increase, ~35x volume increase, and ~4x resolution enhancement over state-of-the-art biomolecular ultrasound.

Conclusions:

• Nonlinear sound-sheet microscopy offers a significant advancement for high-resolution, volumetric imaging in biological research.
• This technique expands the possibilities for studying complex biological functions in intact, thick tissues.
• The method provides a powerful new tool for preclinical research and diagnostics.