Pre-Analytical Stage (Part 1 | F) Flashcards Preview

Histopathology and Cytologic Techniques (Lecture) > Pre-Analytical Stage (Part 1 | F) > Flashcards

Flashcards in Pre-Analytical Stage (Part 1 | F) Deck (99)
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1
Q

True or False

There are already anatomists as early as 17th century

A

True

2
Q

What are the 2 concepts / fields under anatomic path?

A

1) Autopsy
2) Surgical Path
3) Cytopath

3
Q

True or False

Modern day pathos now can bridge the gap between the beginning of disease and its end stage

A

True

4
Q

True or False

The nature of work and type of sxs in anatomic path are not highly complex

A

False, because the nature of work and type of sxs in anatomic path are highly complex

5
Q

What are the 3 stages present in anatomic path?

A

1) Pre-analytical
2) Analytical
3) Post-analytical

6
Q

What are the 2 principles (that are derived / adapted from clinical path) employed in anatomic path?

A

1) Quality assurance

2) Quality management

7
Q

What is the process involved in surgical path? Explain it and its principle

A

1) Pt (who is the source of all sxs) has a complain
2) Hence, pt went to the surgeon (who extracts relevant clinical info and manages the lesion [either via biopsy / excision for dx])
3) The sx (diseased organ / tissue) removed by the surgeon from the pt will be submitted in the histopath lab (where sx is received and where sx accessioning occurs)
4) Then grossing of sx is also done in the histopath lab
5) Then sx will be stored (duration is dependent)
6) Then the grossed tissue will be processed by histotech / medtech
7) Then histotech / medtech will produce a slide
8) The slide produced is the interpreted by the patho and is translated into a std report (report generation)
9) The report generated will be relayed back to the surgeon / clinician (in a timely manner)
10) Then pt will start treatment (/ if additional treatment is present) subsequently
11) Then once dx is present, it’s the time for report generation (whereas this report is the result)

8
Q

What are the steps involved in sx processing?

A

1) Embedding
2) Cutting
3) Deparaffinization
4) Staining
5) Clearing
6) Mounting
7) Labeling

9
Q

Who are the diff staffs composing the surgical lab?

A

1) Dependent managers
2) Medtechs / histotechs
3) Clerical support
4) Pathos (including residents)
5) Lab aids

10
Q

What is the action / responsibility of department managers?

A

They are in-charge w/ the overall management of the section

11
Q

What is the action / responsibility of the medtechs / histotechs?

A

They are in-charge of processing

12
Q

What is the action / responsibility of the clerical support?

A

They are mostly stationed in the receiving, accessioning, and report generation steps

13
Q

What is the action / responsibility of the pathos?

A

They are the ones who does the analysis

14
Q

What are the purpose of histopathologic / cytology studies?

A

1) To diagnose
2) To confirm dx
3) To treat
4) To assess px
5) To assess treatment
6) To screen for disease

15
Q

When / in terms of receiving histopathologic sxs, what should be noted?

A

1) Request forms
2) Sx containers
3) Fixative used
4) Logbooks / Sx accessioning
5) Charging

16
Q

What is the purpose of fixation?

A

To preserve tissues permanently in as life-like state as possible

17
Q

When should fixation be done (in the case of surgical path)?

A

As soon as possible after removal of the tissues

18
Q

When should fixation be done (in / w/ autopsy)?

A

Soon after death

19
Q

Why should fixation be done as soon as possible after the removal of the tissues (for surgical path) or soon after death (w/ autopsy)?

A

To prevent autolysis

20
Q

True or False

There is a perfect fixative

A

False, because there is no perfect fixative

21
Q

What is the fixative that comes the closest when it comes of it being a perfect fixative?

A

Formaldehyde

22
Q

The type of fixative to be used is dependent on what?

A

1) Type of tissue present

2) Features to be demonstrated

23
Q

What are the 5 major grps of fixatives (w/c are classified accdg to mechanism of action)?

A

1) Aldehydes
2) Mercurials
3) Alcohols
4) Oxidizing agents
5) Picrates

24
Q

What are the fixatives under the grp of aldehydes?

A

1) Formaldehyde

2) Glutaraldehyde

25
Q

What is the mechanism of action of formaldehyde?

A

The tissue is fixed by cross-linkages formed in the proteins, particularly between lysine residues

26
Q

True or False

The cross-linkage formed in the proteins (via the use of formaldehyde) do harm the structure of proteins greatly, so that antigenicity is not lost

A

False, because the cross-linkage formed in the proteins (via the use of formaldehyde) does not harm the structure of proteins greatly, so that antigenicity is not lost

27
Q

What is the fixative that is good for immunoperoxidase techniques?

A

Formaldehyde

28
Q

What makes formaldehyde good for immunoperoxidase techniques?

A

The cross-linkages (formed in the proteins) does not harm the structure of proteins greatly, so that antigenicity is not lost

29
Q

What is the other name for formaldehyde?

A

Formalin

30
Q

What are the characteristics of formalin?

A

1) It penetrates the tissue well
2) But its penetration is relatively slow
3) It is the most forgiving of all fixatives when conditions are not ideal, and there is no tissue that it will harm significantly

31
Q

What is the std solution of formaldehyde?

A

10% neutral buffered formalin (NBF)

32
Q

What is the purpose of using a buffer?

A

It prevents acidity that would promote autolysis and cause precipitation of formol-heme pigment in the tissues

33
Q

On what are formalin used?

A

For all routine surgical pathology and autopsy tissues when an H and E slide is to be produced

34
Q

True or False

Due to the nature and characteristics of formalin (whereas it also smells bad), most clinicians and nurses should be careful in handling it

A

True

35
Q

What is the mechanism of action of glutaraldehyde?

A

It causes deformation of alpha-helix structure in proteins

36
Q

Is glutaraldehyde good to be used for immunoperoxidase staining? Why or why not?

A

No, because it causes the deformation of alpha-helix structure in proteins

37
Q

What are the characteristics of glutaraldehyde?

A

1) It fixes very quickly
2) However, it penetrates very poorly
3) It gives the best overall cytoplasmic and nuclear detail

38
Q

Since glutaraldehyde fixes very quickly, it is so good to be used for what?

A

Electron microscopy

39
Q

What is the std solution of glutaraldehyde?

A

2% buffered glutaraldehyde

40
Q

What is the mechanism of action of mercurials?

A

Its mechanism of in terms of fixing tissue is unknown

41
Q

What is the component of mercurials?

A

Mercuric chloride

42
Q

What are the fixatives under the grp of mercurials?

A

1) B-5

2) Zenker’s solution

43
Q

What are the characteristics of mercurials?

A

1) These penetrate relatively poorly
2) These cause tissue hardness
3) These fixes fast
4) These gives excellent nuclear detail

44
Q

Where can mercurials be best used / applied?

A

For fixation of hematopoietic and reticuloendothelial tissues

45
Q

Since mercurials contain mercury, what must be done to these fixatives?

A

These must be disposed of carefully

46
Q

What are the fixatives under the grp of alcohols?

A

1) Methyl alcohol (methanol)

2) Ethyl alcohol (ethanol)

47
Q

What are the characteristics of alcohols?

A

1) These are protein denaturants
2) These are not used routinely for tissues because these cause too much brittleness and hardness
3) These are very good for cytologic smears

48
Q

Why are alcohols very good for cytologic smears?

A

Because these act quickly and give good nuclear detail

49
Q

Who are the professionals that are marketed w/ spray cans of alcohol fixatives?

A

Physicians (who does PAP smears)

50
Q

As an alternative to spray cans of alcohol fixatives, can cheap hairsprays be used?

A

Yes, because these also do just as well compared to spray cans of alcohol fixatives

51
Q

What are the fixatives under the grp of oxidizing agents?

A

1) Permanganate fixatives
a. Potassium permanganate
2) Dichromate fixatives
a. Potassium dichromate
3) Osmium tetroxide

52
Q

What are the characteristics of oxidizing agents?

A

1) These cross-link proteins
2) But these cause extensive denaturation
3) Even if some of these have specialized applications, these are used very infrequently

53
Q

What is the fixative under the grp of picrates?

A

Bouin’s solution

54
Q

What is the component of picrates?

A

Picric acid

55
Q

What is the mechanism of action of picrates?

A

It is unknown

56
Q

What are the characteristics of picrates in comparison w/ mercurials?

A

1) These does almost as well as mercurials (in terms of nuclear detail)
2) But these does not cause as much hardness (like mercurials)

57
Q

What is the characteristic of picric acid?

A

It is an explosion hazard (especially in dry form)

58
Q

What is the characteristic of picric acid (as a solution)?

A

Everything it touches are stained yellow, including the skin

59
Q

What are the factors affecting fixation?

A

1) Buffering
2) Penetration
3) Volume of fixative
4) Temperature
5) Concentration
6) Time interval

60
Q

At what pH is fixation best carried out?

A

Close to neutral pH, in the range of 6 - 8

61
Q

What is the fxn / purpose of buffering (/ buffer)?

A

Since hypoxia of tissues lowers the pH, a buffering capacity in the fixative is needed to prevent excessive acidity

62
Q

Acidity favors the formation of what?

A

Formalin-heme pigment

63
Q

What are the characteristics of the formalin-heme pigment present due to acidity?

A

These appears as black, polarizable deposits in tissue

64
Q

What are the exs of common buffers?

A

1) Phosphate bicarbonate
2) Cacodylate
3) Veronal

65
Q

Commercial formalin is buffered w/ what buffer and at what pH?

A

Phosphate; at a pH of 7

66
Q

Penetration of tissues depends on what?

A

It depends upon the diffusability of each individual fixative (w/c is a constant)

67
Q

What are the fixatives that penetrate the best?

A

1) Formalin

2) Alcohol

68
Q

What is the fixative that penetrates the worst?

A

Glutaraldehyde

69
Q

What is the capacity of penetration of mercurials and other fixatives?

A

Somewhere in between best and worst

70
Q

What should be done to the tissue prior to fixation to prevent the interferences that may occur due to improper penetration of the fixative?

A

Section the tissues thinly (2 - 3 mm)

71
Q

True or False

Penetration into a thick section will occur more rapidly than for a thin section

A

False, because penetration into a thin section will occur more rapidly than for a thick section

72
Q

True or False

The volume of fixative is not impt, hence, it should not be considered / observed

A

False, because the volume of fixative is impt

73
Q

What is the fixative to tissue ratio?

A

10:1

74
Q

What happens if not enough / improper volume of fixative is used?

A

Ideal fixation is not achieved

75
Q

What should be done to partially put a resolution when improper volume of fixative is used?

A

Change the fixative at intervals to avoid exhaustion of the fixative

76
Q

What is the external action that can be done to enhance fixation?

A

Agitation of the sx

77
Q

What is the result of increasing the temp (as w/ all chemical rxns)?

A

The speed of fixation is increased

78
Q

What is the limit of increasing the temp (in terms of fixation)?

A

The tissue should not be cooked

79
Q

True or False

Hot formalin will fix tissues slower

A

False, because hot formalin will fix tissues faster

80
Q

What is often the 1st step on an automated tissue processor?

A

Using hot formalin for fixing tissues

81
Q

What should be done to the concentration of fixative that will be used?

A

It should be adjusted to the lowest lvl possible

82
Q

Why should the concentration of the fixative be adjusted down to the lowest lvl possible?

A

Because you will expend less money for the fixative

83
Q

At what percent of concentration is formalin best?

A

10%

84
Q

What is the range of percentage of concentration where glutaraldehyde is best at?

A

0.25% - 4%

85
Q

What are the effects if the fixative used is present at a too high concentration?

A

1) Fixatives w/ too high concentration may adversely affect the tissues
2) Artefacts will be produced (similar if excessive heat is present)

86
Q

Is time interval very impt also?

A

Yes

87
Q

What is being pertained in time interval?

A

It is the time interval from removal of tissues to fixation

88
Q

True or False

The faster you can get the tissue and fix it, the better

A

True

89
Q

If tissue is left out, what should be done?

A

Artefacts will be introduced due to drying

90
Q

As a resolution to tissues being dry if fixation is not done promptly, what should be done?

A

The tissue should be kept moist w/ saline

91
Q

What are the effects if the tissue is not present in fixative for a long period of time?

A

1) More cellular organelles will be lost
2) More nuclear shrinkage is present
3) Artifactual clumping will occur

92
Q

What is present along w/ the sxs received in the surgical path?

A

A request form

93
Q

What are the components present in the request form?

A

1) Pt info
2) History
3) Description of the site of origin

94
Q

How is sx accessioning done?

A

The sxs are accessioned by giving them a sp. # that will identify each sx for each pt

95
Q

What should be done to acquire easy recognition of the sx, reduction of identification errors, and to acquire orderly storage & retrieval?

A

Redundancy of info

96
Q

What are the 3 types of fees present in the histopath lab?

A

1) Processing fee
2) Professional fee
3) Hospital fee

97
Q

Processing fee is based on what?

A

Sx size

98
Q

What are the possible sizes of the sx that will be processed?

A

1) Small
2) Medium
3) Large
4) Radical

99
Q

Professional fee is based on what?

A

1) Type of sx
2) If service provided or done is either diagnostic or confirmatory
3) Room rate