HTL Tissue Processing & Fixation 2

Question 1

During tissue processing, the graded alcohol series typically ends at which concentration before clearing?

Accepted Answer

100% (absolute) ethanol

Answer

70% ethanol

Answer

80% ethanol

Answer

95% ethanol

Question 2

What is the optimal paraffin infiltration temperature range used in automated tissue processors?

Accepted Answer

50–60°C

Answer

37–42°C

Answer

65–75°C

Answer

80–90°C

Question 3

A tissue specimen shows shrinkage artifact and poor nuclear detail after processing. The most likely cause is:

Accepted Answer

Excessive dehydration time in high-concentration alcohol

Answer

Insufficient fixation time

Answer

Too long in the clearing agent

Answer

Under-infiltration with paraffin

Question 4

Which embedding medium is used for frozen sections when rapid diagnosis is required?

Accepted Answer

Optimal cutting temperature (OCT) compound

Answer

Paraffin wax

Answer

Epoxy resin

Answer

Celloidin

Question 5

The fixative Bouin's solution is best suited for which type of tissue?

Accepted Answer

Testicular and gastrointestinal biopsies

Answer

Large surgical resections

Answer

Bone marrow trephine biopsies

Answer

Brain tissue for neuropathology

Question 6

Tissue that has undergone autolysis prior to fixation will most likely show:

Accepted Answer

Ghost outlines of cells with loss of nuclear detail

Answer

Enhanced nuclear staining

Answer

Increased cytoplasmic eosinophilia only

Answer

No histological changes

Question 7

The term 'cold ischemia time' in tissue handling refers to:

Accepted Answer

Time from tissue removal to placement in fixative

Answer

Time the tissue spends in fixative

Answer

Duration of paraffin infiltration

Answer

Time the tissue spends in the cryostat