Overview of Histology and 3D Reconstruction
Why do histology and 3D reconstruction?
Histology is the practice of embedding tissue in plastic or paraffin wax, slicing it into thin sections, and staining it with dye to visualize the tissue. It is commonly used for diagnosing illnesses in animals and also for understanding the structures of organisms.
If you photograph and align your sections of tissue, you can create a 3D representation of any tissue, bone, cell, neuron, or other structure for quantitative and qualitative evaluation.
With MRI and microCT scans becoming ever more available and affordable, you might wonder why anyone should bother with histology and 3D reconstructions. But histology is still the best technique available for investigating morphology down to a cellular level! No affordable technology exists to compete with the detailed results you can get from this method.
This is a juvenile toad skull embedded in a type of HPMA plastic.
Holes are drilled around the tissue to allow orientation and alignment of the photographed sections after slicing.
The tissue of the specimen is thinly sliced with a microtome (left).
After slicing, the sections are stained, photographed, and aligned to create a 3D movie of the tissue.
This video shows the right half of a toad skull. It starts at the eyeball and moves back through the ear structures. The head is on its side.
This is a 3D model of a toad ear, complete with surrounding muscles.
Bones are absent from this view but are included in the full model.
Here is another toad ear model, simplified to only include the inner, middle and outer ear structures along with the opercularis system.
Yellow - Tympanic Membrane
Dark Blue - Tympanic Annulus
Light Blue - Columella/Stapes + Footplate
Green - Operculum
Pink - Opercularis Muscle
Orange - Inner Ear and Vestibular System