Bendable graded index lens-based laser-scanning optical-resolution photoacoustic microendoscopy

Area of Science:

• Biomedical optics
• Medical imaging technology
• Minimally invasive diagnostics

Background:

• Conventional microendoscopy faces limitations in flexibility and resolution for in-situ biological studies.
• Developing 3D flexible microendoscopy with cellular resolution is crucial for accessing novel biological insights.
• Previous work introduced bendable Graded Index (bGRIN) lens two-photon microendoscopy, showing promise for robust imaging.

Purpose of the Study:

• To enhance existing bGRIN lens microendoscopy by integrating photoacoustic imaging.
• To develop a distal, scan-free bGRIN lens photoacoustic microendoscopy (bGRIN-PAM) system.
• To demonstrate the feasibility of bGRIN-PAM for high-resolution in-situ imaging.

Main Methods:

• Integration of photoacoustic imaging with a flexible bGRIN lens microendoscope.
• Development of a distal scan-free imaging system.
• Characterization of optical resolution (lateral ~2 μm, axial ~60 μm), field of view (100.6 μm), and penetration depth (up to 600 μm).

Main Results:

• Successful demonstration of bGRIN-PAM with high optical resolution and penetration depth.
• Achieved lateral resolution of approximately 2 μm and axial resolution of approximately 60 μm.
• Validated the system through microendoscopic imaging of mouse hairs.

Conclusions:

• The developed bGRIN-PAM system represents a significant advancement in minimally invasive imaging.
• This technology offers a powerful tool for cellular-resolution, in-situ biological investigation.
• bGRIN-PAM has the potential to unlock new avenues in understanding biological mechanisms.