Lesson 5:

Question 1

Commonly used Dehydrating Agents (AACDTT)

Answer 1

Alcohol
Acetone
Cellosolve
Dioxane
Tetrahydrofuran
Triethyl Phosphate

Question 2

Recommended for routine dehydration of tissues and the “Best dehydrating agent” because it is fast acting

Answer 2

Ethyl alcohol

Question 3

3 types of Dehydrating Agent of Alcohol

Answer 3

Ethyl Alcohol
Methyl Alcohol
Butyl Alcohol

Question 4

Toxic dehydrating agent, primarily employed for “blood and tissue films” for smear preparations

Answer 4

Methyl alcohol

Question 5

Slow dehydrating agent, producing less shrinkage and hardening than ethyl alcohol

Recommended for tissues which do not require rapid processing

Answer 5

Butyl Alcohol

Question 6

Identify the Dehydrating Agent

Rapid-acting dehydrating agent utilized for “most urgent biopsies” which it dehydrates in 30 minutes to 2 hours

Highly flammable, poorly penetrating

Answer 6

Acetone

Question 7

Excellent dehydrating and clearing agent readily miscible in water, melted paraffin, alcohol, and xylol

Produces less tissue shrinkage compared to alcohol dehydration

Tissue can be left in this reagent for long periods of time without affecting staining property

Extremely dangerous

Answer 7

Dioxane

Question 7

Clearing is also called as?

Answer 7

De-alcoholization

Question 7

Dehydrates rapidly

Combustible at 110-120F and toxic by inhalation, skin contact, and ingestion

Answer 7

Cellosolve

Question 8

Both hydrates and clear tissues since it is miscible in both water and paraffin

Can dissolve many substances including fats and is in itself miscible with:

lower alcohols
ether
chloroform
acetone
benzene
xylene

Answer 8

Triethyl Phosphate

Question 8

This follows “Dehydration”

Answer 8

Clearing

Question 9

Similar with Triethyl Phosphate but is toxic if ingested or inhaled

Answer 9

Tetrahydrofuran (THF)

Question 10

This step “prepares tissue for infiltration”

Answer 10

Clearing

Question 11

Two types of “Clearing Agents”

Answer 11

Organic Solvent
Oils

Question 12

In the “Clearing” process, the tissue becomes hard and brittle leading to problems in cutting if it stays for how many hours?

Answer 12

Longer than 3 hours (>3 hours)

Question 12

The absolute (100%) alcohol present in the tissue is best cleared using? (3)

Answer 12

Xylol (agent of choice)
Chloroform
Toluene

Question 13

Commonly used Clearing Agents (8)

Answer 13

Xylene
Toluene
Benzene
Chloroform
Cedarwood Oil
Aniline Oil
Clove Oil
Carbon Tetrachloride

Question 13

Identify the Clearing Agent:

Preferred by some as clearing agent in the embedding process of tissues because it penetrates and clears tissue “rapidly”

Used for “urgent biopsies and routine purposes”
Clearing Time: 15-60 mins (Rapid Acting)

Answer 13

Benzene

Question 14

4 Types of Organic Solvent (Clearing Agents)

Answer 14

Xylene
Toluene
Benzene
Chloroform

Question 14

Clearing Agent that is rapid and causes hardening, brittleness, and shrinkage of tissue

Answer 14

Organic Solvent

Question 15

5 Types of Oil (Clearing Agents)

Answer 15

Cedarwood Oil
Aniline Oil
Clove Oil
Carbon Tetrachloride
Methyl Benzoate and Methyl Salicylate

Question 15

Identify the Clearing Agent:

Colorless
Clearing Time: 30 mins to 1 hour
Used for both embedding and mounting procedures
Suitable for most routine histologic processing schedules: <24 hours
Tissue block size: <5mm

Answer 15

Xylene

Question 16

Identify the Clearing Agent:

Substitute for Xylene or Benzene
Used for embedding and mounting procedures
Clearing Time: 1-2 hours

Answer 16

Toluene

Question 17

Identify the Clearing Agent:

Clear both “paraffin” and “celloidin” sections during the embedding process
Clearing Time: 2-3 days (extremely slow)
Used for:

CNS tissues
Cytological studies (smooth muscle and skin)

Answer 17

Cedarwood Oils

Question 17

Identify the Clearing Agent: In embedding, it is slower than xylene Cause less brittleness Tissue Block Size: up to 1 cm (Thick Blocks) Does not become translucent Causes minimum shrinkage and hardening of tissues and used for routine work and: Tough tissues (skin, fibroid, and decalcified) Nervous tissues Lymph nodes Embryos

Answer 17

Chloroform

Question 18

Identify the Clearing Agent: Clears "70% alcohol) without excessive tissue shrinkage and hardening "Not normally utilized" as a routine clearing agent but is rather recommended for clearing: Embryos Insects Very delicate specimens

Answer 18

Aniline Oil

Question 19

Identify the Clearing Agent: Causes "minimum shrinkage of tissues" Quality is not guaranteed due to its tendency to become "adulterated" Wax impregnation after clearing with oil is slow and difficult Tissue becomes brittle, aniline dye are removed and celloidin is dissolved Expensive

Answer 19

Clove Oil

Question 20

Identify the Clearing Agent: Clearing tissue for embedding Similar properties to "Chloroform" but cheaper Considerable tissue hardening and is dangerous to inhale on prolonged exposure due to its highly toxic effects

Answer 20

Carbon Tetrachloride

Question 21

Identify the Clearing Agent: Slow acting clearing agents used for "Double Embedding Techniques"

Answer 21

Methyl Benzoate and Methyl Salicylate

Question 22

A process of assigning an identification code, usually a combination of numbers and letters, for the specimen to properly distinguish it from others without the use of the patient’s name

Answer 22

Accessioning and Numbering

Question 22

Fun Fact: All tissues submitted to the histopathology laboratory must, without exception, be subjected to one or more of the different methods of fixation

Answer 22

Heck Yeah! Jigsaw!

Question 23

For routine fixation, do we use freezants, heat, or chemical solutions?

Answer 23

Chemical Solutions (Fixatives)

Question 23

This preserves the cells and tissues in their natural state

Answer 23

Fixation

Question 23

Fun Fact: Fixation has a "bactericidal" effect which protects the technician from the pathogens present in the tissue sample

Answer 23

Yippie! You da goat!

Question 24

What is the size of the tissue?

Answer 24

1-2 cm long x 1-2cm wide x 4-5mm thick

Question 25

True or False Eyeball and brain, if possible, are not cut into small slices, they need to be processed as whole organs

Answer 25

True

Question 26

2 Types of Infiltration Media

Answer 26

Water Miscible Water Immiscible

Question 26

What kind of wax is used in routine infiltration?

Answer 26

Paraffin wax

Question 27

2 major Embedding Media

Answer 27

Paraffin Wax Celloidin

Question 27

Other name for Infiltration

Answer 27

Impregnation

Question 27

Most popular, but not the best, dehydrating agent available

Answer 27

Ethanol

Question 27

In dehydration, what is the preferred concentration of ethanol?

Answer 27

Ascending concentration (70% to 100%)

Question 28

It is the process whereby the clearing agent is completely removed from the tissue and replaced with a medium that will completely fill all the tissue spaces and cavities

Answer 28

Infiltration (Impregnation)

Question 29

A properly melted paraffin wax appears clear, while a turbid one indicates ___________

Answer 29

inadequate melting

Question 30

2 Types of Paraffin Wax

Answer 30

Soft Wax (low melting point) Hard Wax (high melting point)

Question 30

Paraffin wax is melted in the oven set __ to ___ above the melting point of the paraffin wax

Answer 30

2-5C

Question 31

Embedding is also called as?

Answer 31

Blocking/Casting

Question 31

It is a process by which the infiltrated tissue is placed into a precisely arranged position in a mold containing a medium which is then allowed to solidify

Answer 31

Embedding

Question 32

It is the container wherein the surface of the section to be cut is cast

Answer 32

Boat

Question 32

To the tissue for proper embedding, the pathologist may notch with a scalpel or mark with ________, the side of the tissue opposite that to be cut

Answer 32

India ink(inking)

Question 32

L-shaped strips of metals where tissues are embedded

Answer 32

Leuckhard L-pieces