5.1-PROBLEMS AND SHIT NI MICROTOMY Flashcards
1
Q
What problem arises when surfaces/edges of the block are not parallel?
A
Sections fail to form ribbons
2
Q
What is the remedy for blocks with non-parallel surfaces/edges failing to form ribbons?
A
Re-trim the block
3
Q
What problem occurs when the horizontal surface of the block is not parallel to the knife?
A
Sections fail to form ribbons
4
Q
What is the remedy for blocks with horizontal surfaces not parallel to the knife that are failing to form ribbons?
A
Re-adjust and reorient the block
5
Q
What problem occurs when paraffin wax is too hard?
A
Sections fail to form ribbons
6
Q
What is the remedy for hard paraffin wax causing sections to fail to form ribbons?
A
Coat horizontal edges of block with wax of lower melting point
7
Q
What problem occurs when the knife is tilted too much?
A
Sections fail to form ribbons
8
Q
What is the remedy for a knife tilted too much that causes sections to fail to form ribbons?
A
Reduce the tilt
9
Q
What problem occurs when sections are too thick?
A
Sections fail to form ribbons
10
Q
What is the remedy for overly thick sections failing to form ribbons?
A
Readjust the thickness of the sections
11
Q
What problem occurs when the knife is dull?
A
Sections fail to form ribbons
12
Q
What is the remedy for a dull knife causing sections to fail to form ribbons?
A
Hone and strop
13
Q
What problem occurs when the knife is blunt?
A
Sections roll up on cutting
14
Q
What is the remedy for a blunt knife causing sections to roll up
A
adhere
15
Q
What problem occurs when the tilt of the knife is too great?
A
Sections roll up on cutting
16
Q
What is the remedy for an overly tilted knife causing sections to roll up
A
adhere
17
Q
What problem occurs when the knife edge is dirty?
A
Sections roll up on cutting
18
Q
What is the remedy for a dirty knife edge causing sections to roll up
A
adhere
19
Q
What problem occurs when the knife has a blunt or dull spot
A
or produces an irregular knife edge?
20
Q
What is the remedy for a blunt/dull spot or irregular knife edge causing a curved
A
crooked
21
Q
What problem occurs when the edges of the block are not parallel but round or wedge-shaped?
A
Ribbon is curved
22
Q
What is the remedy for blocks with non-parallel or round/wedge-shaped edges causing a curved
A
crooked
23
Q
What problem occurs when the knife is not parallel to the block?
A
Ribbon is curved
24
Q
What is the remedy for a knife not parallel to the block that is causing a curved
A
crooked
25
What problem occurs when the knife is blunt or dull?
Sections are compressed
26
What is the remedy for a blunt/dull knife causing sections to be compressed
wrinkled
27
What problem occurs when the paraffin block is warm and soft?
Sections are compressed
28
What is the remedy for a warm
soft paraffin block causing sections to be compressed
29
What problem occurs when the knife edge is coated with paraffin?
Sections are compressed
30
What is the remedy for a knife edge coated with paraffin causing sections to be compressed
wrinkled
31
What problem occurs when sections are too thin?
Sections are compressed
32
What is the remedy for overly thin sections causing sections to be compressed
wrinkled
33
What problem occurs when the microtome set screw is loose?
Sections are squashed (width of each section is less than that of the block)
34
What is the remedy for a loose microtome set screw causing squashed sections?
Tighten the screw
35
What problem occurs when the tilt of the knife is too vertical?
Sections are squashed (width of each section is less than that of the block)
36
What is the remedy for a knife with an overly vertical tilt that is causing squashed sections?
Reduce the tilt
37
What problem occurs when the bevel of the knife is lost due to incorrect sharpening?
Sections are squashed (width of each section is less than that of the block)
38
What is the remedy for a bevel that is lost due to incorrect sharpening causing squashed sections?
Re-sharpen
39
What problem occurs when a bubble or dirt is formed in the embedding medium?
A hole is formed in the section
40
What is the remedy for a bubble or dirt formed in the embedding medium that causes a hole to form in the section?
Re-embed in freshly filtered wax if necessary
41
What problem occurs when the tissue is not processed properly and will not form a section (especially if the center is raw)?
A hole is formed in the section
42
What is the remedy for unprocessed tissue causing a hole in the section?
Re-process tissue
43
What problem occurs when an under-processed portion of tissue bursts on contact with warm water?
A hole is formed in the section
44
What is the remedy for an under-processed portion of tissue bursting upon contact with warm water that causes a hole in the section?
Re-process tissue
45
What problem occurs when there is a hard spot in the tissue due to calcium?
A hole is formed in the section
46
What is the remedy for hard spots due to calcium causing a hole to form in the section?
Once embedded in paraffin wax
47
What problem occurs when the tilt of the knife is too great or bevel is not cleared
hence the object is compressed against the knife edge?
48
What is the remedy for an overly tilted knife or uncleared bevel causing sections of unequal thickness?
Reduce the tilt
49
What problem occurs when the clamp set screw on the knife or block holder is loose?
Sections of unequal thickness are produced
50
What is the remedy for a loose clamp set screw causing sections of unequal thickness?
Tighten the screw
51
What problem occurs when blocks are too large?
Sections of unequal thickness are produced
52
What is the remedy for blocks that are too large that are causing sections of unequal thickness?
Cut blocks into smaller fragments
53
What problem occurs when blocks are too hard?
Sections of unequal thickness are produced
54
What is the remedy for blocks that are too hard that are causing sections of unequal thickness?
Soften the blocks in detergent or phenol
55
What problem is indicated when sections adhere to the knife or other microtome parts?
Static electricity due to low atmospheric humidity
56
What is the remedy for sections adhering to the knife due to static electricity?
Breathe out or blow gently on the block and knife to break up static electricity
57
What problem is indicated when sections adhere to the knife or other microtome parts?
Knife edge is dirty
58
What is the remedy for sections adhering to the knife due to a dirty knife edge?
Clean the knife edge
59
What problem is indicated when sections adhere to the knife or other microtome parts?
Knife edge is dull
60
What is the remedy for sections adhering to the knife due to a dull knife edge?
Sharpen the knife
61
What problem is indicated when sections adhere to the knife or other microtome parts?
Knife tilt is too great
62
What is the remedy for sections adhering to the knife due to an overly tilted knife?
Reduce the tilt
63
What problem is indicated when a ribbon is split or lengthwise vertical scratches are seen on sections?
Nicks or damage on the knife edge
64
What is the remedy for lengthwise scratches due to nicks on the knife edge?
Sharpen the knife
65
What problem is indicated when a ribbon is split or lengthwise vertical scratches are seen on sections?
Dirty embedding
66
What is the remedy for lengthwise scratches due to dirty embedding?
Re-embed in freshly filtered wax
67
What problem is indicated when a ribbon is split or lengthwise vertical scratches are seen on sections?
Knife edge is dirty
68
What is the remedy for lengthwise scratches due to a dirty knife edge?
Clean knife edge with xylene
69
What problem is indicated when a ribbon is split or lengthwise vertical scratches are seen on sections?
Tilt of knife is too great
70
What is the remedy for lengthwise scratches due to an overly tilted knife?
Reduce the tilt
71
What problem occurs when sections are lifted from the knife on upstrokes?
Knife tilt is too great
72
What is the remedy when knife tilt is too great and sections are lifted from knife on upstrokes?
Reduce the tilt
73
What problem occurs when sections are lifted from the knife on upstrokes?
Knife is dull
74
What is the remedy when knife is dull and sections are lifted from knife on upstrokes?
Sharpen the knife
75
What problem occurs when sections are lifted from the knife on upstrokes?
Paraffin is too soft or room temperature is warm
76
What is the remedy when the paraffin is too soft due to warm room temperature and sections are lifted from knife on upstrokes?
Cool paraffin wax in ice water
77
What problem occurs when resistance is felt on the lower part of the section during cutting?
Tilt of knife is too small
78
What is the remedy when resistance is felt and tilt of knife is too small?
Increase the tilt
79
What problem occurs when horizontal or parallel lines or furrows appear across the section ("chatters")?
Knife edge vibrates due to hardness of tissue
80
What is the remedy for chatters due to tissue hardness?
Treat with phenol during processing or collodionize
81
What problem occurs when horizontal or parallel lines or furrows appear across the section ("chatters")?
Tilt of knife is too great
82
What is the remedy for chatters due to overly tilted knife?
Sharpen the knife
83
What problem occurs when horizontal or parallel lines or furrows appear across the section ("chatters")?
Knife is blunt
84
What is the remedy for chatters due to a blunt knife?
Sharpen the knife
85
What problem occurs when the section cut is sometimes thin
sometimes thick?
86
What is the remedy for sections that are sometimes thin
sometimes thick due to a blunt knife?
87
What problem occurs when the section cut is sometimes thin
sometimes thick?
88
What is the remedy for sections that are sometimes thin
sometimes thick due to a knife that is not clamped properly?
89
What problem occurs when the section cut is sometimes thin
sometimes thick?
90
What is the remedy for sections that are sometimes thin
sometimes thick due to a loose knife or block holder?
91
What problem occurs when the section cut is sometimes thin
sometimes thick?
92
What is the remedy for sections that are sometimes thin
sometimes thick due to small knife tilt?
93
What problem occurs when the knife makes a hard metallic scraping or ringing sound on backstroke
when section is cut?
94
What is the remedy for hard metallic scraping sound due to knife tilt being slanted or too big?
Readjust the tilt
95
What problem occurs when the knife makes a hard metallic scraping or ringing sound on backstroke
when section is cut?
96
What is the remedy for hard metallic scraping sound due to hard tissue?
Take fresh block treated with phenol during processing
97
What problem occurs when the knife makes a hard metallic scraping or ringing sound on backstroke
when section is cut?
98
What is the remedy for hard metallic scraping sound due to a thin knife blade?
Change the knife
99
What problem occurs when frozen tissue crumbles and comes off the block holder when cut?
Freezing is not adequate
100
What is the remedy for frozen tissue that crumbles and comes off block holder that is due to inadequate freezing?
Refreeze the tissue block
101
What problem occurs when frozen tissue chips into fragments when cut?
Tissue is frozen too much
102
What is the remedy for frozen tissue that chips into fragments when cut that is due to too much freezing?
Warm the tissue with the fingers
103
What problem occurs when ribbons are crooked?
Top and bottom edges of block are not parallel to edge of block sides or blocks are not perpendicular to the blade
104
What is the remedy for crooked ribbons that are due to block edges not being parallel or perpendicular to the blade?
Adjust the block holder to make the block edges parallel to the knife
105
What problem occurs when sections are too thick?
Wrong micrometer setting
106
What is the remedy for sections that are too thick due to a wrong micrometer setting?
Microtome needs recalibration
107
What problem is shown on trimming when tissue smells of clearing agent?
Clearing agent not completely removed due to insufficient impregnation
108
What is the remedy for tissue smelling of clearing agent due to insufficient impregnation?
Block is trimmed down nearest to the tissue
109
What problem occurs when tissue is opaque and section cutting is difficult due to presence of alcohol?
Insufficient clearing
110
What is the remedy when tissue is opaque due to insufficient clearing?
Repeat clearing; if object has already been embedded
111
What problem occurs when tissue shrinks away from wax when trimmed?
Insufficient dehydration
112
What is the remedy when tissue shrinks away from wax when trimmed?
Repeat the whole procedure
113
What problem occurs on trimming when wax appears crystalline?
Contaminated wax
114
What is the remedy for contaminated wax on trimming?
Re-embed in freshly filtered wax
115
What problem occurs on trimming when wax appears crystalline?
Block not cooled rapidly enough
116
What is the remedy for wax appearing crystalline due to block not being cooled rapidly enough?
Re-embed in freshly filtered wax
117
What problem occurs when the paraffin block
after cooling
118
What is the remedy for moist and crumbling paraffin block after cooling that is due to insufficient impregnation?
Repeat paraffin impregnation
