Tissue Processing and Assessment in Pathology
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Questions and Answers

What is the primary purpose of using a fixative in tissue processing?

  • To enhance the natural color of the tissue
  • To increase tissue solubility for better staining
  • To accelerate the decomposition process
  • To prevent bacterial decomposition and autolysis (correct)

During gross examination of a solid organ, what is the maximum thickness allowed for slices?

  • 10 mm
  • 3 mm
  • 5 mm (correct)
  • 7 mm

Which of the following is NOT a requirement for fixative during the fixation process?

  • Should accelerate cellular decomposition (correct)
  • Should preserve tissue in its natural state
  • Should be non-toxic and non-allergic
  • Should be economically viable

How should tissue samples be labeled prior to processing to prevent smudging?

<p>Using printed labels or graphite pencil (B)</p> Signup and view all the answers

What is the role of clearing processes in tissue processing?

<p>To remove water and prepare tissue for embedding (D)</p> Signup and view all the answers

What is the primary purpose of fixation in tissue processing?

<p>To preserve tissues in a life-like state (A)</p> Signup and view all the answers

Which fixative is known for its effectiveness in immuno-histochemistry techniques?

<p>Formalin (D)</p> Signup and view all the answers

What is the fastest fixative among the options provided?

<p>Ethanol (A)</p> Signup and view all the answers

Which group of fixatives is known for its penetration speed and nuclear detail?

<p>Alcohols (B)</p> Signup and view all the answers

What is the first step in the paraffin tissue processing technique?

<p>Dehydration (C)</p> Signup and view all the answers

Which of the following is a disadvantage of using mercurial fixatives?

<p>Poor penetration and tissue hardness (A)</p> Signup and view all the answers

What is the purpose of the clearing process in tissue processing?

<p>To prepare tissues for embedding in paraffin (B)</p> Signup and view all the answers

Which fixation method is considered the most perfect among the techniques discussed?

<p>Celloidin technique (B)</p> Signup and view all the answers

Which of the following is not a component of the major groups of fixatives?

<p>Clearing agents (A)</p> Signup and view all the answers

Which of the following statements is true regarding paraffin embedding?

<p>It uses dehydrated and cleared tissues. (C)</p> Signup and view all the answers

What is the optimal pH range for fixation to achieve the best results?

<p>6-8 (B)</p> Signup and view all the answers

Which fixative is primarily associated with Bouin's solution?

<p>Picric acid (A)</p> Signup and view all the answers

What is the recommended volume ratio of fixative to tissue for effective fixation?

<p>10:1 (A)</p> Signup and view all the answers

During gross examination, what is typically done with the specimen once it is received?

<p>Parts of it are placed in a plastic cassette. (C)</p> Signup and view all the answers

What is the maximum thickness of sections that can typically be made from paraffin-embedded tissues?

<p>5-8 microns (A)</p> Signup and view all the answers

Why might different colored inks be used during specimen examination?

<p>To identify different areas when malignancy is suspected. (C)</p> Signup and view all the answers

Which process allows fixed tissue to be transformed into a suitable form for microscopic sectioning?

<p>Embedding (B)</p> Signup and view all the answers

What effect does increasing the temperature have on the fixation process?

<p>Increases the speed of fixation. (A)</p> Signup and view all the answers

What characteristic of the fixative is crucial for the effective penetration into tissues?

<p>Diffusability (A)</p> Signup and view all the answers

What temperature range is typically maintained within a cryostat for freezing tissue sections?

<p>-20 to -30 C (A)</p> Signup and view all the answers

What is the primary purpose of the clearing process in tissue preparation?

<p>To prepare the tissue for embedding in paraffin. (D)</p> Signup and view all the answers

Which step must occur before staining paraffin-embedded tissue sections?

<p>Deparaffinization of the slides (B)</p> Signup and view all the answers

What is the primary purpose of using strong mineral acids in the decalcification process?

<p>To remove calcium rapidly (A)</p> Signup and view all the answers

When performing sectioning with a microtome, what is a crucial characteristic of the knife used?

<p>It must be very sharp. (A)</p> Signup and view all the answers

Which solvent is used to transition slides from paraffin to alcohol during the deparaffinization process?

<p>Xylene (C)</p> Signup and view all the answers

What is the main advantage of using EDTA for decalcification of tissues?

<p>It safely removes calcium without damaging cells. (B)</p> Signup and view all the answers

What is the purpose of coverslipping stained tissue sections?

<p>To protect the tissue and preserve the section. (C)</p> Signup and view all the answers

What is one disadvantage of using organic acids such as acetic acid in the decalcification process?

<p>They have a slow action on dense cortical bone. (D)</p> Signup and view all the answers

Which method has been shown to reduce the time required for embedding fixed tissues significantly?

<p>Applying fewer steps in the embedding process. (B)</p> Signup and view all the answers

Which of the following should be avoided in the sectioning of tissues with a microtome?

<p>Using a dull knife. (A)</p> Signup and view all the answers

What is the primary purpose of dehydration in tissue processing?

<p>To prevent cellular distortion during embedding (A)</p> Signup and view all the answers

Which factor does NOT influence the duration tissues are kept in each alcohol strength during dehydration?

<p>Initial temperature of the tissue (C)</p> Signup and view all the answers

Which clearing agent is noted for its tolerance to small amounts of water in tissues, though it is more expensive than xylene?

<p>Toluene (A)</p> Signup and view all the answers

What is a major disadvantage of using acetone as a dehydrant in tissue processing?

<p>It is a health hazard if used in large quantities. (B)</p> Signup and view all the answers

Which statement correctly describes the clearing process in tissue processing?

<p>It removes water from tissues using xylene. (A)</p> Signup and view all the answers

What is indicated by the term 'turbulence' during the dehydration process?

<p>The disruption caused at the water-ethanol interface (A)</p> Signup and view all the answers

Which of the following conditions affects the number of steps during dehydration?

<p>The delicacy of the tissue (A)</p> Signup and view all the answers

Why is extensive exposure to clearing agents considered harmful to tissue?

<p>It leads to excessive shrinkage or hardness of the tissue. (B)</p> Signup and view all the answers

The freezing technique is regarded as the most common method of tissue processing.

<p>False (B)</p> Signup and view all the answers

Formaldehyde is considered the best fixative for preservation due to its rapid penetration into tissue.

<p>False (B)</p> Signup and view all the answers

Mercurial fixatives can cause hardness in tissue but facilitate excellent nuclear detail.

<p>True (A)</p> Signup and view all the answers

The celloidin technique is primarily used for biopsy samples as it provides the fastest processing.

<p>False (B)</p> Signup and view all the answers

Oxidizing agents are classified as one of the five major groups of fixatives used in histology.

<p>True (A)</p> Signup and view all the answers

10% neutrally buffered formalin is the standard solution used for aldehyde fixation.

<p>True (A)</p> Signup and view all the answers

Alcohols, such as methanol and ethanol, are unsuitable for cytologic smears due to their slow action.

<p>False (B)</p> Signup and view all the answers

Dehydration involves the abrupt removal of water from tissue using a single grade of ethyl alcohol.

<p>False (B)</p> Signup and view all the answers

During the dehydration process, turbulence can cause damage or distortion to cellular components.

<p>True (A)</p> Signup and view all the answers

The volume of alcohol used for dehydration should be 10-20 times that of the tissue.

<p>False (B)</p> Signup and view all the answers

Xylene is an alcohol-soluble substance commonly used in the clearing process.

<p>False (B)</p> Signup and view all the answers

Chloroform is considered a rapid clearing agent despite being a health hazard.

<p>True (A)</p> Signup and view all the answers

Toluene is three times less expensive than xylene and works well in clearing tissues.

<p>False (B)</p> Signup and view all the answers

The duration for which tissues are kept in alcohol depends solely on the size of the tissue.

<p>False (B)</p> Signup and view all the answers

Formalin is only used in the dehydration step and not in any other part of tissue preparation.

<p>False (B)</p> Signup and view all the answers

Methyl salicylate is rarely used in clearing due to its low cost and pleasant aroma.

<p>False (B)</p> Signup and view all the answers

The primary tool used for sectioning tissues is called a cryostat.

<p>False (B)</p> Signup and view all the answers

Deparaffinization is necessary before applying water soluble dyes to the tissues.

<p>True (A)</p> Signup and view all the answers

Frozen sections are generally processed using automated stainers for efficiency.

<p>False (B)</p> Signup and view all the answers

EDTA is known for its quick action in decalcifying dense cortical bone.

<p>False (B)</p> Signup and view all the answers

Strong mineral acids can quickly remove calcium but can damage cellular morphology.

<p>True (A)</p> Signup and view all the answers

The usual temperature range maintained within a cryostat is about 0 to -10 degrees Celsius.

<p>False (B)</p> Signup and view all the answers

Acetic and formic acids are classified as strong acids for decalcification processes.

<p>False (B)</p> Signup and view all the answers

Sections of tissue need to be embedded in paraffin to be properly stained.

<p>False (B)</p> Signup and view all the answers

The process of coverslipping a stained section involves applying a thin glass cover.

<p>True (A)</p> Signup and view all the answers

Histological technique aims solely to preserve the structural integrity of the tissue in preparation for microscopic examination.

<p>False (B)</p> Signup and view all the answers

Specimens thicker than 1 cm will have their fixation compromised and typically cannot be processed effectively.

<p>True (A)</p> Signup and view all the answers

Using far fewer steps can significantly reduce the time required for embedding fixed tissues.

<p>True (A)</p> Signup and view all the answers

The maximum recommended thickness for tissue samples submitted for histopathology is 5 mm.

<p>False (B)</p> Signup and view all the answers

Decalcification is a necessary process for all types of tissue specimens submitted for histopathological examination.

<p>False (B)</p> Signup and view all the answers

The primary function of histological fixation is to preserve the architecture of the tissue after exposure to a variety of reagents.

<p>True (A)</p> Signup and view all the answers

Dimethoxypropane (DMP) serves only as a dehydrating agent and does not react chemically with water.

<p>False (B)</p> Signup and view all the answers

The critical shrinkage point of collagen is approximately 75°C.

<p>False (B)</p> Signup and view all the answers

Paraffin shrinks 12% in volume upon solidifying, while Paraplast plus shrinks 14% by volume.

<p>False (B)</p> Signup and view all the answers

Biopsy specimens should be transported in a metal container with 10% formalin to prevent autolysis.

<p>True (A)</p> Signup and view all the answers

Once a biopsy is obtained, it should be immediately placed in a container without any fixative.

<p>False (B)</p> Signup and view all the answers

Automation in tissue processing typically involves instruments that require manual timing adjustments.

<p>False (B)</p> Signup and view all the answers

In ulcerated tumors, biopsies should only be taken from the diseased tissue for proper diagnosis.

<p>False (B)</p> Signup and view all the answers

Crushing or squeezing tissue with forceps is recommended during biopsy procedures.

<p>False (B)</p> Signup and view all the answers

The embedding process is critical because tissues must be oriented properly in the paraffin block.

<p>True (A)</p> Signup and view all the answers

Acetone is preferred as the dehydrating agent due to its effectiveness in the processing of all types of tissues.

<p>False (B)</p> Signup and view all the answers

Flashcards

Dehydration

Gradual removal of water from tissue using increasing concentrations of alcohol to prevent shrinking.

Clearing

Replacing alcohol with a substance (like xylene) that dissolves paraffin wax for embedding.

Tissue Dehydration Steps

Dehydration involves a series of increasing alcohol concentrations (e.g., 70%, 95%, 100%).

Clearing Agent

A substance used to replace alcohol in tissue preparation, allowing paraffin wax to be used as an embedding medium.

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Xylene

Common clearing agent used in histological preparation; miscible with paraffin.

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Tissue Shrinkage

Uncontrolled removal of water can cause cell distortion.

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Alcohol Concentration Gradient

A series of increasing alcohol concentrations used in tissue dehydration.

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Clearing Time

Time needed for clearing depends on tissue size and type.

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Tissue Processing

The process of preparing tissues for microscopic examination, primarily involving dehydration and clearing.

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Fixation

Preserving tissue to prevent decay and maintain its structure.

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Formalin

A common fixative, type of aldehyde, that penetrates well but is relatively slow.

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Fixatives

Substances used to preserve tissues, to halt decay, and maintain tissue structure.

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Histology Laboratory

Lab where tissue specimens are processed for microscopic examination.

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Paraffin Technique

The most common tissue processing method.

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Specimen Accession

Assigning a unique number to identify each tissue sample.

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Biopsy

A small tissue sample taken from a patient.

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Automated tissue processor

A machine that automates the preparation of tissues for microscopy.

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Sectioning

Cutting tissue into thin slices (4-6 microns) using a microtome.

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Frozen sections

Tissue sections made using a cryostat (refrigerated microtome).

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Cryostat

A refrigerated microtome for making frozen sections of tissue.

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Staining

Adding dyes to tissue sections to highlight specific structures.

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Paraffin wax deaffination

Removing paraffin from tissue to allow stains to penetrate.

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Coverslipping

Protecting and preserving tissue sections by adding a thin glass cover.

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Decalcification

Removing calcium from bone or calcified tissues before embedding.

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Mineral acids (decalcification)

Strong acids used for rapid decalcification, but can damage tissue morphology.

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Organic acids (decalcification)

Weaker acids, slower for decalcification. Better for dense cortical bone.

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Fixative Role

A substance that stops tissue decay, preserves its natural state, and prepares it for microscopic examination.

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Why Fixative is Important

Fixatives prevent tissue breakdown, preserve cellular structures, and make the tissue suitable for staining and processing.

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Types of Fixatives

Fixatives are categorized based on their applications: tissue (for whole structures), cytological (for cellular studies), and histochemical (for specific cell components).

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Tissue Processing Steps

Tissue processing includes a series of steps such as fixation, dehydration, clearing, and embedding, preparing the tissue for microscopic examination.

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Blocking and Labeling Tissues

After processing, the tissue is embedded in wax, cooled, trimmed, and labeled to create a block for microscopic examination.

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Oxidizing Agents

Fixatives that use permanganate (like potassium permanganate) or dichromate (like potassium dichromate), or osmium tetroxide, to preserve tissue.

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Picrates

Fixatives containing picric acid, like Bouin's solution, are used to preserve tissues.

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Fixation Penetration

How well a fixative enters tissue depends on how well the fixative can diffuse.

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Fixation Temperature

Higher temperatures speed up fixation, like with most chemical reactions.

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Fixative Concentration

Use the lowest concentration of fixative that still works for effective preservation.

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Fixation Time Interval

Fix tissues as quickly as possible after removal to prevent degradation.

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Gross Examination

First step in pathology: examining tissue removed from the body and placing it in a cassette for processing.

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Ink Marking

When malignancy is suspected, ink is used to mark tissue margins to be analyzed later.

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What is the most common tissue processing method?

The paraffin technique is the most widely used method for preparing tissues for microscopic examination.

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What are the main steps in tissue processing?

The main steps involve dehydration (removing water) and clearing (replacing water with a substance that dissolves paraffin wax).

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What is an aldehyde?

A type of fixative, like formaldehyde, that preserves tissue well and is commonly used in histology.

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What is the role of a fixative?

Fixatives prevent decay and maintain tissue structure, making the tissue suitable for staining and processing.

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Why is tissue processing important?

Tissue processing allows us to examine tissues under a microscope, helping diagnose diseases and understand biological processes.

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Why Dehydration is Needed?

Tissues fixed in water-based solutions cannot be directly embedded in paraffin wax. Dehydration removes water to prepare tissues for paraffin embedding.

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Dehydration Steps

Dehydration uses a series of increasing alcohol concentrations (e.g., 70%, 95%, 100%) to gradually remove water from tissues.

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Dehydration Time

The duration of each alcohol step depends on tissue size, fixative used, and tissue type.

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Why is Clearing Needed?

After dehydration, alcohol must be replaced with a substance that dissolves paraffin wax for embedding. This is called clearing.

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What is a Clearing Agent?

Clearing agents replace alcohol, making tissues ready for paraffin embedding. Xylene is a common clearing agent.

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Xylene vs. Toluene

Xylene is the most common clearing agent. Toluene is better for tissues with water, but more expensive.

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Alternatives to Xylene

Other clearing agents exist like acetone (fast but flammable), chloroform (slow and hazardous), and methyl salicylate (nice smell, expensive).

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Clearing Agent Hazards

Overexposure to clearing reagents can cause excessive hardness or shrinkage of tissues.

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Tissue Size Limit

Tissue submitted for microscopic examination should be no thicker than 3 mm and not exceed the size of the slides used.

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Specimen Thickness

For most solid tissues, specimens are typically cut into pieces that are 10 to 15 mm wide and 2 to 3 mm thick.

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Calcification/Ossification

Areas with calcification or hardening should be separated and treated with acid to remove the calcium before processing.

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Fixative Mechanism

Fixatives work by precipitating proteins, essentially solidifying the tissue and preventing breakdown.

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Microtome

A specialized instrument used to cut extremely thin slices (4 to 6 microns) of embedded tissue for microscopic examination.

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Deparaffinization

The process of removing paraffin wax from tissue slices to allow water-soluble dyes to penetrate.

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EDTA (Decalcification)

A safe and effective decalcifying agent, although slow, poor at penetrating tissue, and expensive in large quantities.

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Dimethoxypropane (DMP)

A chemical used in tissue processing that acts as both a dehydrating and clearing agent. It reacts with water to produce methanol and acetone, both of which help remove water from the tissue.

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Paraffin Embedding

The process of surrounding tissue with molten paraffin wax, which solidifies to create a solid block for slicing (sectioning).

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Embedding Medium

A substance used to surround and solidify tissues for sectioning. Paraffin is the most common example.

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Collagen Shrinkage

Exposure to high heat during paraffin embedding can cause shrinkage of collagen fibers in the tissue, distorting its structure.

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Paraffin Shrinkage

Upon solidification, paraffin shrinks in volume. This shrinkage can affect the size and shape of the embedded tissue.

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Tissue Alignment in Embedding

During embedding, tissue must be carefully oriented within the paraffin block to ensure proper slicing and analysis.

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Biopsy Size and Number

Larger lesions should be sampled more extensively with multiple biopsies to ensure capturing all potential diagnostic areas.

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Biopsy from Ulcerated Tumours

Biopsies should be taken from the edge of ulcerated tumors, including both normal and diseased tissue.

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Minimize Tissue Damage

Avoid crushing or squeezing tissues with forceps during biopsy to maintain tissue integrity.

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Study Notes

Tissue Processing

  • Tissues for disease diagnosis are processed in a histology lab to create microscope slides
  • Tissue samples come from biopsies or surgery or autopsies
  • Three main techniques for preparing tissue sections: paraffin, celloidin, and freezing
  • Specimens are accompanied by a request form including patient info and site of origin
  • Specimens are accessioned by assigning a unique number
  • Tissue processing involves fixing tissue in paraffin, via dehydration and clearing steps

Specimen Assessment

  • Tissue samples sent to the pathology lab are accompanied by a request form
  • This form includes patient information, history, and site of origin
  • The specimens are accessioned, given a unique identifier for each individual patient

Tissue Processing Steps

  • The process of fixing tissue in paraffin is called tissue processing
  • The main steps are dehydration and clearing procedures

Fixation

  • Fixation is preserving tissues in a lifelike state as much as possible
  • Fixation should be carried out as soon as possible to prevent autolysis
  • No perfect fixative exists, but formaldehyde is a good option
  • Various fixatives are available, depending on the tissue type

Types of Fixatives

  • Major groups: aldehydes, mercurials, alcohols, oxidizing agents, picrates
  • Aldehydes: Formaldehyde (formalin), glutaraldehyde; good for immuno-histochemistry; formalin penetrates tissue well but is relatively slow
  • Mercurials: Contain mercuric chloride (e.g., Zenker's); penetrate poorly but rapidly; causes tissue hardness
  • Alcohols: Methyl alcohol (methanol), ethyl alcohol (ethanol); good for cytologic smears, act quickly
  • Oxidizing Agents: Potassium permanganate, potassium dichromate, osmium tetroxide
  • Picrates: Picric acid (e.g., Bouin's solution)

Factors Affecting Fixation

  • Buffering: Fixation at a neutral pH (range of 6-8) is ideal
  • Penetration: The fixative's ability to diffuse into tissue depends on its diffusability
  • Volume: Fixative volume should be approximately 10:1 in relation to tissue volume
  • Temperature: Higher temperature increases the speed of fixation
  • Concentration: The concentration needs to be adjusted to the lowest possible level
  • Time Interval: The time between tissue removal and fixation

Gross Examination

  • Tissues for diagnosis are examined in the pathology department
  • Examination involves describing the specimen and placing it in a small plastic cassette
  • The cassettes are stored in a fixative for further processing into a paraffin block

Tissue Processing Steps (Continued)

  • Tissues are held firmly to allow for cutting thin sections with a sharp knife
  • Firmness achieved through embedding or freezing
  • The tissue, after fixation, must be processed into a format that can be sectioned into microscopic slides

Clearing

  • The alcohol is replaced with paraffin wax
  • Materials used includes xylene, benzene, acetone, chloroform, carbon tetrachloride, toluene.
  • Xylene is a routine clearing agent
  • Smaller tissue cleared in 0.5-1 hour, larger in 2-4 hours
  • Chloroform is no longer a preferred clearing agent due to potential health hazards
  • Removing the dehydrant with a substance, similar to paraffin (embedding medium), is called clearing

Impregnation in Paraffin

  • Tissues are put in hot, soft paraffin at 50°C for a period varying from 6-24 hours
  • Tissues are transferred to hot hard paraffin at 55°C for further impregnation in an oven
  • Paraffin penetrates the tissue and hardens it, a necessary step prior to embedding

Wax:

  • The volume of paraffin should be approximately 25-30 times the tissue volume
  • The impregnation duration depends on tissue size, type, and clearing agent usage
  • Impregnation takes about 4 hours for a routine process

Embedding

  • Paraffin, a derivative of crude petroleum, is the typical embedding agent
  • Paraffin melts between 52° and 58°C, infiltrating the cells while hot
  • Impregnation should be performed few degrees above the melting point of paraffin
  • Firmness is achieved using a supporting medium

Cutting (Sectioning)

  • Embedded tissues are cut into thin sections (4-6 microns) using a microtome with a very sharp knife
  • This method allows for the preparation of thinly sliced samples that can be examined under a microscope

Frozen Sections

  • Frozen sections are performed using a cryostat
  • The cryostat is a refrigerated box containing a microtome
  • Frozen sections are used at temperatures ranging from -20 to -30°C
  • Tissue sections are cut and mounted on glass slides

Staining

  • The embedding process is reversed to allow water-soluble dyes to penetrate
  • Slides are depraffinized using xylene, then alcohols, finally water
  • There are no stains applicable to tissues containing paraffin.

Coverslipping

  • A thin piece of glass is placed over the stained section, protecting the tissue from scratches and preserving the tissue section for years

Decalcification

  • Bone samples, as well as other calcified tissues, must be decalcified before embedding and sectioning
  • Mineral acids, organic acids, EDTA, and electrolysis are among the decalcifying reagents used
  • Strong mineral acids remove calcium rapidly, but may damage tissue morphology
  • Organic acids are slower but may be better for dense cortical bone
  • EDTA removes calcium safely, but is slow, penetrates poorly, and is costly

Sampling for Histopathological Examination

  • Tissue specimens should not exceed 3mm in thickness nor be larger than the slides
  • Pieces from solid tissues are typically 10-15mm in surface area and 2-3mm in thickness
  • Discrete calcified areas should be removed and decalcified separately
  • Tissue samples should be wrapped in paper or gauze

General Rules for Biopsy Procedure

  • The number of biopsies increases with the size of the lesion
  • Ulcerated tumors should be biopsied to include the periphery of the tumor, which includes normal tissue.
  • Tissues should not be crushed or squeezed too hard.

Specimen Handling

  • Specimens should be transported in a container of suitable material, like glass, plastic or metal, along with 10% formalin
  • If formalin isn't immediately available, it can be placed in the refrigerator at 4°C to slow down autolysis
  • The container opening should have an adequate size for easy tissue removal after fixation

Examination

  • Proper identification and orientation of the specimen
  • Unlabeled specimens should not be processed
  • Complete histopathology requisition forms include patient name, age, sex, relevant clinical data, surgical findings, operation type, and specific tissue name
  • The examination should be done in an orderly manner, searching all the submitted tissue and placing them in a proper anatomic position, recording specimen type, shape, dimensions, weight, color, surgical margins, consistency and pertinent information

Automated Tissue Processor

  • The whole process is automated for efficiency
  • An instrument moves the tissue through the agents at controlled speeds

Blocking

  • Impregnated tissues are placed in a mold and covered with fresh wax
  • After cooling, it is immersed in cold water for rapid cooling, then cut into individual blocks and each is trimmed.
  • Labels are adhered on the surface of the block.

Histological Technique

  • Deals with tissue preparation for microscopic study
  • The aim is to retain microscopic tissue structures

Fixation (Continued)

  • The process fixes the constituents of cells and tissues in a physical and chemical state to resist subsequent treatment
  • This is achieved by exposing tissues to chemical compounds known as fixatives
  • Solutions for dealing with thick specimens include cutting slices and soaking wool in fixative solution, or injecting fixatives along blood vessels.

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Tissue Processing PDF

Description

Explore the essential techniques of tissue processing used in pathology labs for disease diagnosis. This quiz covers the steps involved, including fixation, dehydration, and accessioning specimens, as well as the importance of accompanying request forms. Test your knowledge on the preparation of microscope slides and the methods used for tissue sample processing.

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