August 26, 2013
I can’t figure out why this phrase even occurred….blonde fundus. I was looking up some other eye things this morning and where the words originated, like Greek or Latin derivations, and wanted to write about this one condition called amaurosis fugax but decided it’s just a bad problem that needed too much of my brain power. So I decided to look up some other things and settled on how we doctors might describe how a retina looks. Usually I just tell a patient that the back of their eye (their retina) was normal and healthy. But for some reason I was taught a special way to describe the appearance of a patient’s retina…probably because I should know that the variations in the appearance of a human retina can vary significantly. So to simply explain what a blonde fundus is, check the color of your hair. If it’s naturally blonde, or long ago it was :), then your retina probably is blonde. But the retina is not really blonde. It just has less pigment in it like your hair. I wish I could say for sure if the two were related to specific genes and I’d bet so.
There are some different layer structures in the retina where you find certain types of cells. You know, rods and cones and stuff. Well there’s a couple of other layers back there called the choroid (pronounced core-oid) and retinal pigment epithelium. I don’t know why there’s epithelium deep in the eye. I always thought epithelium was my skin. Maybe schools teach what our outer skin cells are called first and that just made me not understand what epithelium really is. Whatever the reason, these retinal layers in the eye contain melanin. A smaller amount of melanin means the retina looks redder. Look at the pictures I included below. And yep, in case you wondered, those pictures of red eyes from photographs are showing you, generally, who has the blonde fundus (or plural – fundi). The angle of light has to be just right though to get that red eye effect. Since the red eyes in pictures, or more specifically, the red pupils are the result of the redder color in the retina (red comes from blood) we see this effect reflecting from the camera flash back out of the eye.
Anyway, if your doctor says you have a blonde fundus you’re ok. But if the doctor doesn’t say it, you’re still ok. It’s just something we learned in school so we can call your retina names! Here’s one more name, tigroid fundus. You’re ok if you have that too! Oh, the word fundus is used to describe the bottom or end part of an organ so it’s not just an eye word. Maybe instead of saying bottoms up when we finish our bottled beer we could say fundus up?