Histology | Techniques
A place for histology professionals to teach, learn, and share with each other inventive embedding and microtomy techniques, tips, and tutorials so that we may advance our skillset. Send us your ideas.
Histology Embedding | techniques, tips, and tutorials
| Embedding is the Foundation of Exceptional Slides |
Quality embedding is essential for producing exceptional histology microscope slides. In my opinion embedding is THE most important and demanding bench in the histology department. It is also often the most overlooked bench because errors and poor quality at embedding can be corrected by good microtomy. However, corrections made at microtomy typically come at a cost; slowed cutting output, patient tissue loss, overall decreased section quality, and not to mention cutting tech frustration can all be exacerbated by poorly embedded blocks.
Considering that the fixation, pre-processing and processing steps should already be established and standardized for all the tissue types your lab handles; embedding is the first step that requires the skill and experience of a histotech. And given the immense tissue variability (size, type, orientation, condition, etc.) it is also the bench least likely to be successfully automated. In this section you will find techniques, tips, and tutorials that will help you improve your embedding skillset.
Essential Histology Embedding Equipment
- embedding tampers
- embedding center
- plastic scraper (putty knives can work)
- disposable gloves
- proper adjustable lighting
- dulled scalpel
- calibrated thermometer
- heated block peeler or dulled knife
Helpful Histology Embedding Equipment
- magnifier (preferably lighted)
- bright flashlight (finding specimens that pop out of bags or cassettes)
- small fan
- heated paraffin pot
- gauze (4x4)
- sequins (marking scant or special specimens)
- adjustable ergonomic chair
- height adjustable work table
- adjustable computer monitor stand
- keyboard cover
- adjustable foot stool
Histology embedding tampers are critical for correctly flattening specimens so that the bottom of specimens are completely flush with the bottom of the mold. It is important that specimens lie flat and even in the correct orientation so that a minimal amount of facing (patient tissue loss) needs to be done at microtomy. Our Embedding Tamper Package includes all of the tampers we think you need to elevate your embedding, with customizability available to fit any of your needs.
The MagnifiedLS Standard Tamper has a .75"x.75" square head that can fit inside most medium size square molds. We chose this as our standard tamper head size because we feel it is the optimal size to embed most specimen types encountered in a histopathology laboratory. You also have the ability to choose your knob size in order to fit your hand and tamping style perfectly. We use an 'arcade joystick' configuration to allow you to move the knob in any direction with accuracy while utilizing larger muscle groups to put downward pressure on the specimen. Other tampers force you to use a lot of finger and hand strength in order to put downward pressure; increasing the possibility of fatigue, discomfort, and the chances of injury to the wrist and hand.
If your specimen has uneven features you can utilize our Pen Style Tampers to fit in the nooks and crannies and tamp those areas down. The Pen Style Tampers are great for tamping needle biopsies, the fatty connective tissue margins of skin excisions, and specimens that have multiple fragments of varying thickness that a larger tamper is unable to evenly tamp (prostate chips, uterus excisions, LEEPs, etc.). I often quickly use the Pen Style Tampers after using the Standard Tamper to tamp areas of the specimen missed by the larger tamper.
When using our MagnifiedLS histology embedding tampers, instead of just pushing down on the specimen, use the specimen as a pivot point and work the tamper around in a circular motion as you apply moderate downward pressure (be sure not to overly distort the specimen). This motion works the specimen deeper into the paraffin as heat is transmitted by the tamper through the specimen, melting the underlying paraffin and working it to the sides. Thus requiring less pressure on the specimen to properly tamp it. Just using downward pressure is less effective and can overly distort the specimen if too much pressure is used.
Think about when you are at the beach relaxing and you are trying to dig your feet into the sand. If you just push down into the sand with your feet you don't get very deep. Instead you burrow your feet into the sand by swiveling back and forth dislodging the underlying sand and working it to the sides... Tamping works in a similar fashion.
*Currently Under Construction*