I recently got the news that my vision is going. Age-related blindness is something I was expecting, or possibly something related to my diabetes, but this turns out to be a little different.
The cornea is the clear covering on the outside of the pupil. It is made up of five layers: an outer layer of epithelial cells, a membrane separating them from the stromal layer (which is the main transparent layer), another membrane, and then the inner endothelial cells which protect the stroma from the aqueous humor which lies beyond. The endothelial cells pump any water which may have seeped into the stroma back into the aqueous humor, keeping the stroma clear. Unfortunately these cells are not regenerated, so if anything happens to them, the water is not removed and the stroma goes cloudy and “bumpy.” Vision dims and becomes less sharp as the condition worsens.
In my case, the endothelial cells are dying off, a condition known as ‘Fuchs Endothelial Dystrophy’ or sometimes as just FED. Fortunately there is a transplant treatment available in which donor endothelial cells are inserted under the stromal layer of the cornea. With this treatment I will probably end up with reduced vision, but not complete blindness. My corrected vision will be good enough for me to read, albeit a little more slowly than currently.
Of course, for this to work, there must be donors. Please sign your donor card now. Otherwise my minions will seek you out and hurt you….