Work

Focus-tunable two-photon fiberscope enabling in vivo imaging at selected depths

Year: 2025

Type: article

Abstract: Miniaturized two-photon (2P) imaging devices enable real-time in vivo and in situ imaging at subcellular resolution, highly valuable for clinical applications and basic research (such as neuroscience). However, achieving high-quality volumetric imaging at varying depths remains challenging. In this study, we demonstrated a 2P fiberscope capable of three-dimensional (3D) imaging over a cylindrical volume of a 350 μm diameter and a 400 μm depth. Depth scanning was achieved by incorporating a miniature electrowetting-based varioptic lens (VL) into a two-dimensional (2D) scanning 2P fiberscope, whose focus was tuned by modulating the VL drive voltage. The performance of the fiberscope was demonstrated by ex vivo imaging of fluorescently stained convallaria and GFP mouse brain sections, as well as in vivo dynamic GCaMP-based calcium imaging of cortical neurons in an awake mouse.

Source: Optics Letters

DOI: 10.1364/ol.560869

Authors: Yuehan Liu, Jiayun L. Huang, Xingde Li

Institution: Johns Hopkins University

Language: English

Topic: Advanced Fluorescence Microscopy Techniques

Subfield: Biophysics

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

Open Access status: green

Funders: National Institutes of Health, National Cancer Institute, National Institute of Biomedical Imaging and Bioengineering

Awards: Advancing Thyroid Cancer Diagnostics with AI-enhanced Multimodal Optical Histopathology, Simultaneous two-photon imaging and two-photon manipulation of neural activity in freely behaving mice, 3D Scanning Two-photon Fiberscope Technology for Simultaneous Multi-region Multi-cell-type Imaging in Freely-moving Rodents