Simultaneous Visualization of Corneal Nerves and Immune Cells... A New Path for Dry Eye Diagnosis [Reading Science]

POSTECH, Seoul National University Hospital, and Chung-Ang University Achieve High-Resolution Imaging of Living Cornea Without Fluorescent Labeling

An optical imaging technology that allows for the simultaneous, clear observation of corneal nerves and immune cells—both of which are critical in the recovery process following dry eye syndrome and vision correction surgeries—without the need for fluorescent labeling, has been developed in South Korea. This technology enables real-time tracking of nerve damage and inflammatory response in the living cornea, and is expected to significantly improve the accuracy of diagnosing ocular surface diseases and evaluating post-surgical recovery.

On April 9, the National Research Foundation of Korea announced that a research team led by Professor Kim Ki-hyun of Pohang University of Science and Technology, in collaboration with Professor Yoon Chang-ho's team at Seoul National University Hospital and Professor Kim Kyung-woo's team at Chung-Ang University, has developed a high-performance optical microscopy technique that can simultaneously visualize sensory nerve networks and immune cells within the cornea without any labeling.

Schematic diagram of the optical imaging system based on differential phase contrast (DPC) for corneal nerve and immune cell visualization. Provided by the research team

The cornea is a core tissue for vision formation, densely populated with sensory nerves and immune cells. In particular, corneal nerves are closely linked to dry eye syndrome and are affected during procedures such as LASIK, LASEK, and cataract surgeries, making precise observation essential. However, conventional in vivo confocal microscopy, which is based on reflected signals, suffers from severe speckle noise and produces signal variations depending on nerve orientation, resulting in the appearance of broken nerve fibers.

To address these limitations, the research team developed a differential phase contrast (DPC)-based label-free in vivo imaging technology. Instead of relying on reflected signals, this method converts light refracted by cells into imaging contrast, enabling high-contrast visualization of both corneal nerve networks and immune cells. Compared to conventional methods, nerve fibers appear continuous without breakage, and the morphology of immune cells is visualized with much greater clarity.

The joint research team validated the technology using both normal and damaged mouse models. In normal models, they achieved high-resolution visualization of the corneal nerve network and immune cells; in damaged models, they quantitatively confirmed a reduction in nerve networks and an increase in immune cells. This indicates the technique can be directly applied in tracking dry eye syndrome, neurotrophic keratopathy, and post-surgical nerve recovery.

Improved Accuracy in Tracking Nerve Recovery after LASIK and Cataract Surgery

This technology has significant clinical scalability, as it enables high-resolution three-dimensional imaging of live tissues without fluorescent staining. The research team plans to further optimize the system for human application and to advance it into a precision medical diagnostic platform through clinical studies.

Professor Kim Ki-hyun of Pohang University of Science and Technology stated, "It is significant that we can simultaneously observe nerves and immune cells in living tissues at high resolution without fluorescent labeling. This broadens the scope of application to diagnosing ocular surface diseases, tracking nerve recovery, and even early diagnosis of peripheral nerve degeneration disorders."

The results of this research were published online in the February issue of the international ophthalmology journal 'The Ocular Surface.'

This content was produced with the assistance of AI translation services.