granular layer is specific to skin that's on the outside of a body, it is not mucosal. So this particular fragment that I'm looking at has a granular layer.
Since I see that, that let's me know that it is definitely exterior skin and that's how I know it's skin. And then the next part where it says overlying soft connective, the skin surface sits like on the level and beneath that you have a supporting layer of tissue. The supporting layer of tissue is this connective tissue layer that I'm talking about here.
Then I say there are features of desiccation/drying artifact. This particular piece of tissue that I had that was, you know, was sitting outside on a car door for an extended period of time before, let me back up.
Before I got a chance to put it in formalin, it has been exposed to air, other type of things that can cause it to dry out, that's all desiccation means. It is kind of an artifactual change of it drying out, not being put in preservative, that would kind of halt or stop that process.
So for an extended period of time, I don't know how long it took before it got to me, but those features are there, it is hardened, it dried. I can appreciate those changes under the microscope. Those changes under the microscope look like little circles or kind of like pockets of air, kind of looks like swish cheese, in a way to think how the little pockets of swish cheese are. That's cause the tissue has kind of been affected by these drying changes and causes that artifactual change on my slides, so that's what I'm talking about right there.
Then I say there is a granular layer present within the upper layer of the stratified squamous epithelium.
So that granular layer that I just spoke to you about, that's how I definitively know that this is a skin sample from the outer surface of the body skin surface.
And the stratified squamous epithelium is just how I as a pathologist describe this particular type of skin set. There is different types, but this particular type that you have on your skin is known as stratified squamous epithelium, so it is just a name.
So focally, lightly pigmented keratinocytes are present within the basal layer of the stratified squamous epithelium.
So that's just going back to what I was telling you before, you have that relationship between the melanocytes, who are responsible for making pigment. They give that pigment up to this keratinocyte, who holds onto it and eventually over time, you know, they will migrate up and disappear.
But this particular cell type is not, it is present, but it is not overly pigmented. So it was important for me to describe that to maybe suggest potentially where this piece of tissue may have come from and that's what I'm saying in essence.