Embedding Troubleshooting

Question 1

What is the artifacts name caused by not pressing tissue down uniformly against the base of the mold?

Answer 1

Floating

Question 2

What is the primary cause of the “Floating” artifact?

Answer 2

Tissue not properly flattened by pressing it down uniformly against the base of the mold.

Question 3

What are the corrective actions and prevention methods for “Floating”?

Answer 3

Press tissue down uniformly to ensure all parts are flat on the mold.

Do not allow paraffin to solidify at different rates; work very fast when embedding multiple pieces.

Re-embed.

Question 4

What are the two artifacts that can occur when using an incorrectly sized mold?

Answer 4

Wax compression (when the mold is too large)

Tissue compression (when the mold is too small)

Question 5

What is the corrective action for using a mold that is either too small or too large?

Answer 5

Re-embed in the correct size mold.

Question 6

What is the artifacts name caused by uneven cooling of the wax?

Answer 6

Stratification

Question 7

What is a potential consequence of the Stratification artifact on the tissue?

Answer 7

The block may fall apart and damage the tissue (loss of support).

Question 8

What are the corrective actions and prevention methods for “Stratification”?

Answer 8

Re-embed.

Fill wax adequately and work quickly.

Question 9

You remove a block from the mold and it hasn’t fully solidified. What are the likely causes?

Answer 9

Impatience (removing it too soon).

The cassette was not filled, or not filled adequately with wax.

Question 10

A block was removed from the mold before it was completely cooled. What corrective action should you take, and how can you prevent this in the future?

Answer 10

Corrective Action: Re-embed the tissue.

Prevention:

Allow the block to completely cool before removing it from the mold.

Ensure the cassette is filled adequately with wax.

Question 11

What is the main risk associated with an underfilled wax block?

Answer 11

The block face containing the tissue may detach from the cassette. This leads to a loss of patient identification, which is a major patient safety issue.

Question 12

An underfilled block has been created. What is the most likely cause, and what is the necessary corrective action?

Answer 12

Cause: Not enough wax was dispensed into the cassette.

Corrective Action: Re-embed the tissue.

Question 13

How can you prevent the problem of an underfilled block?

Answer 13

Ensure you fill the back of the cassette with an adequate amount of wax.

Question 14

What are the potential causes of a transcription error?

Answer 14

Not double-checking the numbers.

Distraction.

Illegible handwriting.

Question 15

You discover a mismatch between the number on a cassette and the worklist. What are the required steps to take?

Answer 15

Double-check everything to confirm the error.

Investigate how the error occurred.

File an incident report.

Question 16

What are three potential causes of tissue cracking during the embedding process?

Answer 16

The cold plate being too cold.
Wax on the surface of the specimen solidifying before it is positioned in the mold.
Tissue being shifted after the wax has already solidified.

Question 17

What are the recommended corrective actions and prevention methods for tissue cracking?

Answer 17

Check and adjust the temperature of the cold plate.

Only re-embed the tissue if it becomes difficult to cut on the microtome.

Question 18

What causes a bubble to form underneath the cassette, and what is a potential consequence of this?

Answer 18

Cause: Trapped air during the embedding process.

Consequence: The block face can crack and break when pressure is applied during microtomy.

Question 19

How can you prevent or correct a bubble from forming under the cassette during embedding?

Answer 19

Corrective Action: Re-embed the tissue.

Prevention:

Lower the cassette onto the mold at an angle and decrease the rate of paraffin flow.
Gently lift the cassette when dispensing wax to allow trapped air to escape before moving the block to the cold plate.

Question 20

What are the general rules for orienting tissue in a mold to ensure a good section?

Answer 20

Orient the tissue diagonally in the mold, not parallel to the edges.

Embed the tissue in the center of the mold, ensuring there is a 2mm margin of paraffin around the tissue.

Question 21

When should a tissue be embedded on its edge? Give three examples.

Answer 21

Tissues with walls should be embedded on edge to show all the tissue layers. Examples include cysts, gall bladders, and gastrointestinal tract (GIT) samples.

Question 22

How should tubular structures be oriented, and why? Give two examples.

Answer 22

Tubular structures should be embedded on end (to create a cross-section). This allows for the viewing of the lumen and all the mucosal and muscle layers. Examples include fallopian tubes and appendixes.

Question 23

How should tissues with a hard part (like skin with epithelium or a collagenous capsule) be oriented in the block, and why?

Answer 23

They should be embedded so that the hard part strikes the microtome blade last. Cutting the hard part first can cause tissue compression and tearing.

Question 24

When embedding multiple pieces in one block, how should they be arranged, and why should they not be placed parallel?

Answer 24

They should be arranged in a diagonal line. A parallel arrangement can cause tissue compression during microtomy.

Question 25

What are two key considerations when embedding multiple pieces in a single block to ensure a good outcome for the Pathologist?

Answer 25

Each piece should be embedded on an angle. They must be carefully aligned to ensure the Pathologist does not overlook any piece.

Question 26

You are looking at a slide and the tissue appears in the wrong orientation, making it difficult to assess the layers (e.g., mucosa vs. muscularis). What are the possible causes of this error?

Answer 26

Inking the wrong side. Notching the wrong side. Lack of special instructions from the pathologist. Grossing error (bad grossing).

Question 27

After processing, you notice that the tissue on the slide is "soft and mushy." What are the two most likely causes for this?

Answer 27

The tissue was grossed too thick. The tissue was under-processed.

Question 28

What is "tissue carryover" or "forceps metastasis," and how does it occur?

Answer 28

It is the contamination of one specimen with fragmented tissue from a previous specimen. It is caused by using the same forceps to handle multiple cassettes without cleaning them in between.

Question 29

You are grossing a GI specimen (like a bowel resection). What specific preventive action should you take before grossing to ensure proper embedding later?

Answer 29

Open the GI tract specimen before grossing to prevent it from rolling. Rolling makes it difficult to see and orient the tissue layers during embedding.

Question 30

To prevent "soft, mushy tissue," what steps should be taken during the grossing and processing phases?

Answer 30

Grossing: Cut tissues thinly. Processing: Ensure the tissue is adequately fixed, the processor is in good working order, and a good processing schedule is maintained. (Note: If the tissue is already mushy, it can sometimes be reprocessed as per lab protocol.)

Question 31

A pathologist notes that the tissue is rolled in the paraffin block, making it impossible to see the serosa and mucosa in the same section. What error likely occurred during grossing, and how can it be prevented in the future?

Answer 31

Error: The GI specimen was not opened before grossing, causing it to roll and curl. Prevention: Always open GI tract specimens before grossing to avoid rolling.

Question 32

List two specific actions you can take during embedding and grossing to prevent an "incorrect orientation" error.

Answer 32

During embedding, ensure the correct marked side or notched side is placed face-down in the block. During grossing, complete the embedding worklist properly to ensure correct orientation is clear.

Question 33

You are about to start grossing a small, friable specimen. What simple and effective steps can you take to prevent "tissue carryover" into the next case?

Answer 33

Clean your forceps thoroughly with gauze or tissue paper before and after handling each cassette. Only have one cassette open at a time.

Question 34

What are two common causes of tissue being missing from a cassette during processing?

Answer 34

Tissue lost during the actual processing run. Very small pieces not placed in biopsy bags or filter paper, making them easy to miss during grossing.

Question 35

What should you document during the grossing process to help prevent issues with missing tissue later?

Answer 35

You should document the correct number of pieces during grossing.

Question 36

Besides the cassette itself, what two specific locations should you always check for a missing tissue piece?

Answer 36

The back of the cassette lid. The bottom of the tissue processor.

Question 37

What is the correct way to handle a biopsy bag or filter paper when looking for a small piece of tissue?

Answer 37

You should carefully open the biopsy bag or filter paper.

Question 38

If a piece of tissue is missing, what three steps are part of the corrective action and prevention protocol?

Answer 38

Investigate. Notify the supervisor. File an incident report.

Question 39

According to the troubleshooting guide, where is the first place you should look for a missing tissue piece?

Answer 39

Look around your embedding station, and specifically check the back of the cassette lid.

Question 40

Why should you look at the gross description when a piece of tissue is missing?

Answer 40

To see the tissue type, size, and color so you have an indication of what you are looking for.

Question 41

You find a piece of tissue near the embedding station but are not 100% sure it belongs to the patient you're working on. What should you do?

Answer 41

Create a new cassette with a "query" accession number on it. Embed the found tissue in that new cassette. Cut and stain it with H&E. Give the slide to the pathologist to look at. Document the event in the quality assurance log.

Question 42

After an exhaustive search, you cannot find a piece of tissue. What is the final procedure to follow?

Answer 42

Embed the empty cassette (to show there is no tissue). Notify the pathologist. File an incident report (following the lab's specific protocol for missing tissue).