Mapping tiny corneal nerves to untangle ocular mysteries

Consider the cornea if you will – and most people won't unless they're having a problem. It is the transparent front surface of the eye which allows vision by focusing light as it enters. The cornea is densely packed with multi-tasking nerves that mediate pain, blink reflexes and tear production, all indispensable tasks in the proper maintenance of ocular surface health. Because it is highly innervated, meaning it has a lot of nerve connections, the cornea is a key area for understanding sensory functions.

But it is that same complexity which has made it increasingly difficult to grasp the full nature of how those corneal nerves work, resulting in key knowledge gaps in the field. A University of Houston optometrist researcher is set to fill in the gaps by mapping the cornea and providing a comprehensive analysis of corneal nerves at the morphologic, molecular and functional level.

We are developing methods to selectively label the neurons that innervate the cornea. These neurons make up about 1% of the population of neurons located in the trigeminal ganglia, the peripheral nervous system that mediates pain and other sensory functions."

Anna Matynia, Associate Professor, University of Houston College of Optometry

Matynia has received $1.4 million from Duke University via the National Eye Institute to explore new approaches to disentangle these intricate networks and discover which nerve makes people blink, which creates tears and which nerve tells us our eye is in pain.

Matynia and her team are using advanced imaging, studying genes, and using computers to map the corneal nerves. They are also figuring out which nerves connect directly to the eye and creating a detailed map of how they're all connected.

"These efforts will provide critical clues for understanding corneal structure-function and will lead to an unprecedented cartography," said Matynia. "The advancements from this work will be poised to facilitate a deeper understanding of related pathobiology including neuropathic ocular pain and dry eye disease that will lay the foundation for future translational and clinical research."

Matynia's team includes Daniel R. Saban, Duke University and Victor Perez, University of Miami.