Epiglottis Histology

We are going to be doin histology for a while.  Histology is the microscopic study of human tissue.  We are going to be looking at and discussing different tissue types and layers on a microscopic level.  Even if you don't understand it, I think you will at least find some of the pictures I have taken interesting.

Today's Medical Topic:  Histology of the Epiglottis.

What Are We Looking For:  The epiglottis is a little flap of cartilage that folds over your trachea when you swallow so you don't inhale food and water.  The epiglottis is constructed of a specific type of cartilage called elastic cartilage.  This type of cartilage is unique and really only found in a few places in the body, namely your ears and the epiglottis.

So what are we looking for?  Well first off we want to find the section of elastic cartilag this section should be very distinctive.  We will then discuss the surrounding tissue and how to identify that tissue microscopically.  Are you ready?  Let's do this.

The Tissue Sample:  This is a slide of a section of a human epiglottis and it's surrounding tissue.  It is dyed specifically to show off the elastic cartilage.  So probably the thing that is the darkest, or has soaked up the most dye, is probably the epiglottis.

40x Magnification

So the purple stuff is probably elastic cartilage.  Which is correct.  That is what it is.  As you can see the epiglottis is not just  composed of elastic cartilage, it has other tissues as well.  Let's zoom in.

250x Magnification (Click to make bigger)

Here the elastic cartilage is becoming more distinctive.  Looking closer you can see a thin tissue layer that boarders the cartilage.  This is probably dense irregular connective tissue.  And the larger, lighter areas of wispy tissue adjacent to that is probably loose adipose connective tissue.  It is interspersed with sections of more dense irregular connective tissue.  Let's get closer to see how distinctive these layers are.

400x Magnification

Here we can see how very distinctive everything is.  The elastic cartilage is unmistakable.  Can you see how the fibers in the dense irregular tissue goes in all different directions and are very close together?  And how the adipose tissue shows big globules of fat that take up most of the cell volume?

These distinguishing features do not change between slides.  They might be different colors, but don't let that shake you.  You might even see multiple colors in slides to highlight different features but the shapes and arrangements will stay the same.

Keep it tuned here for more histology.  Tomorrow we look at mammal lung.

Send questions or comments to dudaday@gmail.com

Disclaimer:  I am not a health care provider, any information presented in this blog should not be considered advice it is mearly an outlet to slake my curiosity.  You should always consult your primary medical provider for any concerns or illness.  Unlike Tylenol, I am not approved by the FDA or American Medical Association to treat or provide relief for any ailment.