Clearing

Question 1

Slow-acting clearing agents that can be used when double embedding techniques are required.

Answer 1

Methyl Benzoate and Methyl Salicylate

Question 2

Its properties are similar to chloroform although it is relatively cheaper
Same disadvantage of chloroform
It produces considerable tissue hardening and dangerous to inhale on prolonged exposure due to its highly toxic effects

Answer 2

Carbon Tetrachloride

Question 3

Colorless clearing agent that is most commonly used. Most rapid clearing agent, suitable for urgent biopsies
Clearing time: ½ to 1 hour
Makes tissues transparent
Does not extract aniline dye
Can be used for celloidin sections because it does not dissolve celloidin

Answer 3

Xylene

Question 4

May be used as a substitute for xylene or benzene

Tends to acidify in a partially filled vessel

Answer 4

Toluene

Question 5

Its quality is not guaranteed due to its tendency to become adulterated

Answer 5

Clove Oil

Question 6

Slower in action than xylene but causes less brittleness

Suitable for large tissue specimens. Thicker tissue blocks (up to 1 cm) are can be processed

Answer 6

Chloroform

Question 7

Not normally utilized as a routine clearing agent
Recommended for clearing embryos, insects and very delicate specimens due to its ability to clear 70% alcohol without excessive tissue shrinkage and hardening

Answer 7

Aniline Oil

Question 8

It is preferred as clearing agent in the embedding process of tissues because it penetrates and clears tissues rapidly

Answer 8

Benzene

Question 9

It may damage the bone marrow resulting in aplastic anemia.

Answer 9

Benzene

Question 10

Recommended for central nervous system tissues and cytological studies.

Answer 10

Cedarwood Oil

Question 11

Clearing time: 6 – 24 hours

Recommended for tough tissues, nervous tissues, lymph nodes and embryos

Answer 11

Chloroform