Observation of Corneal Guttae by Plasma-FIB Microscope

(In-Person) Poster Presentation 

Fuchs Endothelial Corneal Dystrophy (FECD) is an inherited disease that leads to blindness. FECD is characterized with the thickening of the Descement’s membrane, corneal endothelial cell loss, and the formation of guttae (deposition of the extracellular matrix). Once corneal endothelial cells are lost, the cornea cannot maintain its transparency. Since these cells do not proliferate in vivo, the current treatment is through a cornea transplant, but this comes with risks such as infection and tissue rejection.

The purpose of my research is to observe the structure of guttae in FECD mice corneas to better understand its condition.

In this study, normal and FECD mouse corneas were compared. After euthanizing the mice, the eyeballs were harvested, and corneas were removed. Then they were stained with osmium tetroxide, fixed with epoxy resin, and microtomed. Finally, the sample was mounted on a 45-degree tilt and cut with a 45 nanoampere oxygen beam at a slice size of 50 nm by a Plasma-FIB microscope to obtain ~700 images. Some issues included the bending of the cornea once harvested and the time it took to image a sample.

We successfully 2D imaged the normal and FECD mouse corneas. The normal mouse corneal endothelium is smooth and thick, but FECD mouse cornea showed signs of bumps and thinness. I’m currently developing these images into 3D models to better analyze them. Overall, I hope that my work will provide information about guttae developed from FECD for future research.