3D-Printed Micro Lens-in-Lens for In Vivo Multimodal Microendoscopy.

Area of Science:

• Biomedical Optics
• Medical Imaging
• Materials Science

Background:

• Multimodal microendoscopes offer co-located structural and molecular insights for disease pathology.
• Conflicting optical requirements (e.g., high NA for fluorescence, low NA for OCT) challenge miniaturized probe design.
• Simultaneous high-quality imaging of multiple modalities in vivo is difficult.

Purpose of the Study:

• To demonstrate a miniaturized lens design optimized for simultaneous fluorescence and optical coherence tomography (OCT) imaging.
• To overcome the optical design challenges posed by conflicting modality requirements.
• To enable advanced in vivo intravascular imaging.

Main Methods:

• Utilized two-photon 3D printing to fabricate a novel lens-in-lens optical design.
• The lens design features distinct optical surfaces for fluorescence and OCT within a 330 µm diameter.
• Integrated the lens into a 520 µm diameter intravascular catheter probe.

Main Results:

• Achieved simultaneous optimization for fluorescence and OCT imaging modalities.
• Demonstrated >10x improvement in fluorescence sensitivity compared to conventional fiber-optic designs.
• Successfully performed the first in vivo simultaneous intravascular OCT and fluorescence imaging of a mouse artery.

Conclusions:

• The developed lens-in-lens design effectively addresses conflicting optical requirements for multimodal imaging.
• This technology significantly enhances fluorescence sensitivity in miniaturized probes.
• Paved the way for advanced in vivo intravascular diagnostics using simultaneous OCT and fluorescence imaging.