F2-RAPID TISSUE PROCESSING Flashcards
(164 cards)
1
Q
Which method allows for faster diagnosis compared to conventional tissue processing
A
Rapid tissue processing
2
Q
Which chemicals are avoided in rapid tissue processing
A
Formalin + Xylene
3
Q
What equipment is used to speed up rapid tissue processing
A
Microwave oven
4
Q
Which system removes fumes during rapid tissue processing
A
Fume extraction system
5
Q
How many specimens can be processed in one hour with rapid tissue processing
A
120 cassettes
6
Q
How long does rapid tissue processing typically take
A
One hour
7
Q
Which process is faster and safer than conventional processing
A
Rapid tissue processing
8
Q
What type of energy does microwave processing use
A
Electromagnetic wave-induced heat
9
Q
How much faster is microwave processing than conventional
A
60–80 percent faster
10
Q
How long does conventional processing typically take
A
2.5 hours
11
Q
Which features are improved with microwave processing
A
Excellent morphology + Sharp nuclear detail + Crisp cellular images
12
Q
How many steps are in microwave processing
A
Four steps
13
Q
Which reagents are used in each step of microwave processing
A
Ethanol one change + Isopropanol one change + Paraffin wax two changes
14
Q
How long is each reagent step in microwave processing
A
15 minutes each
15
Q
Why is microwave processing fast
A
Increased movement in solutions and tissues due to microwave excitation
16
Q
Which device ensures even field of irradiation in microwave processing
A
Magnetic stirrer
17
Q
Which devices are used for temperature control in microwave processing
A
Thermocouple temperature probe and controller
18
Q
Which microwave type cannot be used for tissue processing
A
Household microwave
19
Q
Why can’t household microwave be used
A
No precise temperature control + No magnetic stirrer + No probe and controller
20
Q
How does staining with microwave compare to conventional
A
Shorter time + Better contrast + More intense staining + Less non-specific staining
21
Q
What is the optimum temperature for metallic stains with microwave
A
75–95 degrees Celsius
22
Q
What is the optimum temperature for non-metallic stains with microwave
A
55–60 degrees Celsius
23
Q
What is the configuration of a rapid tissue processor
A
Enclosed system similar to modern vacuum assisted conventional tissue processors
24
Q
How long does rapid tissue processor processing take
A
3 hours
25
How is tissue processed in a rapid tissue processor
Run in batch mode
26
What is the recommended tissue thickness for rapid tissue processing
1.5 millimeters
27
What is the recommended tissue thickness for conventional processing
2–4 millimeters
28
Which technology is used in rapid tissue processors
Low-wattage microwave technology
29
Which reagents are used in rapid tissue processors
Molecular-friendly reagents
30
Which infiltration method is used in rapid tissue processors
Vacuum infiltration
31
How many specimens can be processed per hour in rapid tissue processors
Up to 120 specimens
32
How many cassettes can be processed in an 8-hour shift
960 cassettes
33
How many cassettes are processed every 20 minutes
40 cassettes
34
How long are specimens immersed in each processing retort
15 minutes each
35
How does the quality of rapid tissue processor sections compare to conventional
Comparable or superior
36
Does rapid tissue processing affect staining
No detrimental effects on staining
37
Is antigen retrieval needed for immunohistochemistry with rapid tissue processing
No antigen retrieval needed
38
Which fixative permits recovery of DNA RNA and proteins for molecular analyses
Alcohol-based fixative
39
What is an example of a universal molecular fixative
UMFIX mixture of methanol and polyethylene glycol
40
What are the properties of UMFIX
Excellent cost-effective alternative to formalin + Non-volatile + Active at room temperature
41
What is a commercial example of a rapid tissue processor
Tissue-Tek XPRESS X120
42
What is important for fixative and dehydrating solution penetration
Thin sections about 1.5 millimeters
43
Which tissues require additional steps before rapid tissue processing
Brain + Large tissue blocks
44
What is the workflow like in continuous flow processing
Eliminates batching + Requires ongoing attention + Samples must be removed after each cycle
45
How should paraffin be added to the microwave
In liquid form
46
Why should paraffin be added in liquid form
Microwave energy will not melt paraffin pellets
47
What should be done to tissue in the last step of rapid processing
Bring tissue to the boiling point of the intermedium to flash evaporate remaining alcohol
48
What is the boiling point of ethyl alcohol
82 degrees Celsius
49
What is the boiling point of isopropanol
78 degrees Celsius
50
Which technique provides results within 15–30 minutes
Frozen section
51
How long does rapid tissue processor processing typically take for results
4–5 hours
52
Which method is faster for diagnosis compared to rapid tissue processor
Frozen section
53
Which advantage is associated with frozen section
Faster results
54
Which advantage is associated with frozen section regarding equipment
Less equipment
55
Which advantage is associated with frozen section regarding ventilation
Less need for ventilation
56
Which equipment is primarily used in frozen section
Cryostat + Stains
57
Why is ventilation less important in frozen section
Tissues are fresh and not fixed with formalin
58
Where can frozen section be performed
Pathologist office
59
Which disadvantage is associated with frozen section
Inferior morphologic details and resolution compared to paraffin embedded
60
Which application is most common for frozen section
Rapid pathologic diagnosis during surgery
61
Which diagnoses are made using frozen section
Benign + Borderline + Malignant
62
What happens if cancer cells are found at specimen edges during surgery
Additional tissue may be removed
63
Which application uses frozen section for enzyme activity
Diagnostic and research enzyme histochemistry
64
What condition is required for enzyme activity in histochemistry
Enzymes must be fresh or frozen
65
Which substances are demonstrated using frozen section
Soluble substances such as lipids and carbohydrates
66
Which staining methods are compatible with frozen section
Immunofluorescent + Immunohistochemical + Some specialized silver stains
67
Which method of freezing is most rapid
Liquid nitrogen
68
What temperature range is used for non-fatty unfixed tissues with liquid nitrogen
−10 to −25 degrees Celsius
69
Which disadvantage is associated with liquid nitrogen freezing
Formation of ice crystals or freeze artifacts
70
What happens if blocks are overcooled with liquid nitrogen
Damage to both block and blade
71
Which effect is caused by vapor phase around tissue during liquid nitrogen freezing
Uneven cooling especially in muscle biopsies
72
Which freezing method is excellent for muscle tissue
Isopentane cooled by liquid nitrogen
73
Which freezing method uses aerosol sprays
Fluorinated hydrocarbons
74
Which tissues are suitable for aerosol spray freezing
Small pieces except muscle
75
Which procedure uses carbon dioxide gas
Cold knife procedure
76
Which gas source is used in cold knife procedure
Carbon dioxide cylinder or cryostat
77
Which equipment is used in cold knife procedure
Any microtome in a container with carbon dioxide gas
78
Which material is placed on the microtome stage in cold knife procedure
Filter paper soaked in gum serum
79
How are bursts of carbon dioxide applied in cold knife procedure
Short bursts to freeze filter paper
80
What thickness of tissue block is used in cold knife procedure
3–5 millimeters
81
How is tissue frozen in cold knife procedure
Intermittent bursts of carbon dioxide for 1–2 seconds at 4-second intervals
82
What is the goal of freezing in cold knife procedure
Tissue should be firm enough to section
83
How is the tissue prepared for sectioning in cold knife procedure
Trimmed until surface is flat
84
How is the tissue surface warmed in cold knife procedure
With the finger until hard frozen tissue starts to thaw
85
What is the point called where sections may be cut in cold knife procedure
DewLine
86
What thickness are sections cut in cold knife procedure
10 micrometers
87
How are sections removed in cold knife procedure
With a camel hair brush or finger moistened with water
88
Where are sections transferred after cutting in cold knife procedure
Dish of distilled water
89
How are sections picked up for mounting and staining in cold knife procedure
Individually
90
What factors affect the success of cold knife procedure
Ambient temperature and humidity
91
What is the optimum knife temperature for cold knife procedure
−40 to −60 degrees Celsius
92
What is the optimum tissue temperature for cold knife procedure
−5 to −10 degrees Celsius
93
What is the optimum environment temperature for cold knife procedure
0 to −10 degrees Celsius
94
Which procedure is most commonly used for frozen section
Cryostat procedure
95
What is a cryostat
Insulated microtome in a refrigerated chamber at near −20 degrees Celsius
96
What is the optimum working temperature of a cryostat
−18 to −20 degrees Celsius
97
Which conditions are maintained in a cryostat
Microtome + Knife + Specimen + Atmosphere at same temperature
98
What is required for fresh frozen tissue in cryostat
Tissue must be maintained in frozen solid state during sectioning
99
What temperature must the microtome knife be maintained at in cryostat
Low temperature to prevent complete melting
100
Which materials are used for mounting tissue blocks
Synthetic water-soluble glycols and resins
101
Which commercial compound is commonly used for mounting
O.C.T. compound
102
Which temperature is used for brain
lymph nodes
103
Which temperature is used for non-fatty breast tissue
ovary
104
Which temperature is used for fatty breast and omental tissue
−35 degrees Celsius
105
Which component holds the tissue specimen in place inside the cryostat
Tissue shelf
106
Which component precisely slices frozen tissue
Rotary microtome
107
Which component cuts the tissue into uniform sections
Blade
108
Which component prevents tissue sections from curling
Anti-roll plate
109
How are sections handled in cryostat
One section at a time then loaded on slide
110
What happens to tissue after loading on slide in cryostat
Melts and sticks on slide then stained
111
Which steps summarize cryostat procedure
Embed + Cut + Stain
112
Which process is used for cold sectioning of fixed material for fats lipids and nervous system studies
Freezing previously fixed tissue
113
Which coating should be used on slides for fixed tissue attachment
Albumin or chrome-glycerin jelly
114
How should tissue be prepared for rapid surgical diagnosis before freezing
Immersed in boiling 10 percent buffered formalin for 1–2 minutes
115
Which special fixative is used at 4 degrees Celsius for histochemistry and lipid demonstration
10 percent formol calcium
116
What should be done to alcohol-fixed or stored tissue before sectioning
Washed in water for 12–24 hours
117
Why should alcohol-fixed tissue be washed before sectioning
Alcohol inhibits freezing
118
How are nerve and muscle biopsies divided
Formalin-fixed for paraffin embedding + Unfixed snap-frozen for cryostat sections + Fixation and resin embedding for electron microscopy
119
Which portion of biopsy is stained with H&E and checked with light microscopy
Formalin-fixed for paraffin embedding
120
Which portion of biopsy is snap-frozen for cryostat sections
Unfixed snap-frozen for cryostat sections
121
How is the snap-frozen biopsy portion transported
In saline-dampened gauze on ice
122
Which portion of biopsy is fixed and resin embedded for electron microscopy
Fixation and resin embedding for electron microscopy
123
Which technique is most ideal for preserving tissue for histochemical enzyme studies
Frozen section
124
Which other methods preserve tissue chemically for enzyme studies
Freeze drying + Freeze substitution
125
Why must freezing be rapid for histochemical evaluation
To prevent formation of ice crystal artifacts
126
Which agents are used for rapid freezing
Liquid nitrogen + Isopentane + Pentane + Propane + Dichloro-difluoromethane
127
Which technique is used for rapid freezing of tissue
Quenching
128
What thickness of tissue is used for quenching
2 millimeters
129
Which agents are used for quenching
Isopentane or propane-isopentane
130
What temperature is used for quenching
−160 to −180 degrees Celsius
131
How long does it take for tissue to solidify in quenching
2–3 seconds
132
Which process follows quenching in freeze-drying
Desiccation and sublimation
133
What equipment is used for desiccation and sublimation
High vacuum drying chamber
134
What temperature is used for desiccation and sublimation
−30 to −40 degrees Celsius
135
How long does desiccation and sublimation take
24–48 hours
136
What happens to water during sublimation
Water is sublimated and dehydrated from the tissue
137
Which state transition occurs during sublimation
Direct transition from solid ice to vapor
138
Which materials are used for embedding after freeze-drying
Molten paraffin wax + Soluble waxes + Celloidin
139
Where is infiltration and impregnation performed
Vacuum embedding oven
140
How is tissue sectioned after freeze-drying
In usual routine
141
Which staining is applied after freeze-drying
Specific staining
142
Why is freeze-drying preferred for enzyme studies
Avoids chemical alteration and denaturation of proteins and enzymes
143
Which advantage is associated with freeze-drying
Minimum tissue shrinkage
144
Which advantage is associated with freeze-drying
Tissue processed in fresh state
145
Which advantage is associated with freeze-drying
Minimal chemical change on tissues
146
Which disadvantage is associated with freeze-drying
Time-consuming and expensive
147
Which disadvantage is associated with freeze-drying
More difficult to section
148
Why is tissue brittle and inadequately supported after freeze-drying
Short wax impregnation
149
Which solvents are preferred for processing after freeze-drying
Warm alcohol + Acetone + Mercury
150
How much water should be removed by weight during freeze-drying
70–80 percent
151
Which techniques are freeze-drying used for
Immunocytochemistry + Fluorescent antibody studies of polypeptide and polypeptide + Hormones + Autoradiography + Microspectrofluorimetry of autofluorescent substances + Formaldehyde-induced fluorescence of biogenic amines + Scanning electron microscope
152
Which amines are demonstrated by formaldehyde-induced fluorescence
5-hydroxytryptamine + Adrenaline + Other catecholamines
153
Which technique is similar to freeze-drying in preparing and preserving tissue blocks
Freeze substitution
154
How is tissue fixed in freeze substitution
Rossman’s formula or 1 percent acetone and dehydrated in absolute alcohol
155
How is infiltration and embedding performed in freeze substitution
Same as paraffin section
156
What thickness of specimen is used for freeze substitution
1–3 millimeters
157
Which agent is used to supercool tissue in freeze substitution
3:1 propane-isopentane cooled by liquid nitrogen to −175 degrees Celsius
158
What thickness are cryostat sections cut in freeze substitution
8–10 micrometers
159
Which fluid is used for transferring sections in freeze substitution
Water-free acetone
160
What temperature is used for dissolving ice in freeze substitution
−70 degrees Celsius
161
How long are sections kept in substituting fluid
12 hours to 1 week
162
How are sections prepared for staining in freeze substitution
Floated onto coverslips or slides and allowed to dry
163
Which advantage is associated with freeze substitution
More economical and less time-consuming than freeze-drying
164
Which fluids contain both chemical fixing agent and solvent for ice in freeze substitution
1 percent osmium tetroxide in acetone + Mercuric chloride in ethanol + Picric acid in ethanol
