M2: Rapid tissue processing

Fresh tissue

Body fluids

it is considered potentially infectious

Grossing specimens

It has the highest risk of all histological activities

Histology

Microscopic study of normal tissues in the body

Histopathology

Microscopic study of tissues affected by diseases

Histologic or histopathologic techniques

Procedures adopted for the preparation of material for the microscopic study of tissues

Routine tissue processing

Most common tissue technique

Biopsy

Test for tiny tissue specimen

Surgery or autopsy

Test for whole organ

Surgery or autopsy

Test for very large specimen

Autopsy

Used for dead patients and mortem exam to determine the cause of death

Biopsy

Test where patient is alive and it determines the live view of tissues

FNA

Core needle biopsy

Incisional biopsy

Excisional biopsy

Punch biopsy

Shave biopsy

Curettings

Surgical procedure usually performed to obtain tissue samples

FNA

It is the simplest, least invasive test and uses the smallest needle to collect cell.

22-25

What gauge is used in FNA to aspirate cells for cytologic examination

Vim-silvermann’s

What do you call the needle in FNA

Core needle biopsy

Removes cells and a small amount of surrounding tissue

14-18

Size of the nedle for core needle biopsy

FNA

Biopsy done if there is palpable thyroid noduke

Core needle biopsy

Biopsy done if there is breast lump detected on mammogram

Incisional biopsy

Takes out even more surrounding tissue than CNB but not all

Incisional biopsy

Biopsy for mass suspected of squamous cell carcinoma

Incisional biopsy

Biopsy test that is used on tissues that are too large to be removed

Excisional biopsy

Removes the entire area to be studied

Excisional biopsy

It provides comprehensive histopathologic evaluation and on small lesions where mass has compact border and the surgeon is sure that it will not burst and to remove potential melanoma

Punch biopsy

Primary technique for obtaining diagnostic full thickness skin specimens

Basic general surgical

Suture tying skills

punch biopsy requires these two things

Punch biopsy

Biopsy test used for skin rash to check which layer is affected

Shave biopsy

Small fragments of tissue are shaved from a surface

Shave biopsy

Biopsy test for seborrheic keratosis

Curettings

Tissue is scooped or spooned to remove tissue or growth from body cavity

Curettings

Test for suspected endometrial hyperplasia where you streak tissue from the endometrium

Formalin

Most common preservative

Patient information

Clinical history

Site of origin (description )

In requisition form, the following must be accomplished: —,—,—

Specimen accessioning

A unique combination of numbers assigned to help identify each specimen for each patient to minimize the risk of mislabeling

Destruction of cells or tissues by their own enzymes

Slowed by cold and hastened at room temp

More severe in tissues that are rich in enzymes

Less rapid in elastic and collagen tissue

What occurs when a tissue is removed from the body

Cornea

Most common muscle tissue tested

Structural and chemical composition of cells to be studied

Nature and amount of tissues to be evaluated

Need for urgent or immediate examination

Fresh vs preserved tissue examination

Methods of tissue examination may vary according to the following

Examined in living state

Advantage of fresh tissues

Not permanent

Develop changes observed after death

Disadvantage of fresh tissue

Teasing

Squash preparation

Smear preparation

Touch preparation

Methods of fresh tissue examination

Autolysis

What happens when tissues are removed from the body

Destruction of cells or tissues by their own enzymes

Slowed by cold and hastened at room temperature

More severe in tissues that are rich in enzymes

Less rapid in elastic and collagen tissues

What happens during autolysis

structural and chemical composition of the cells to be studied

nature and amount of tissue to be evaluated

need for urgent or immediate examination

fresh examination s preserved tissue

Methods of examination may vary acc ording to the following

Isotonic salt solution

Normal saline

Ringer’s solution

Where do you immense tissue during teasing or dissociation such as —,—

Phase contrast

Brightfield

What do you use ro examin tissues during teasing or dissociation

Impression smear

Touch smear is also called as

Rapid diagnosis during surgery

Enzyme histochemistry Demonstration of soluble substances such as lipids & carbohydrates

Immunofluorescent and immunohistochemical staining

Some specialized silver stains, especially in neuropathology

Applications of frozen sections in histotech

Rapid diagnosis is necessary

Intraoperative pathology

Demonstrating lipids and nervous tissue

Muscke and nerve biopsies; surgically removed tumor

Frozen section is used when

Microtome with Co2 (cold knife)

Cryostat (cold microtome )

Frozen section can be done in

Rapid processing time

Advantage of cryostat

Poor quality of final slide

Disadvantage of frozen sections

-18 to -20

Working temp of cruostats

Presence of ice crystals

Slow freezing distorts the tissue due to

Ambient temperature

Humidity

Success of cold knife depends upon

-40 to -60

-5 to -10

0 to -10

Cold knife

Knife:

Tissue:

Environment:

-160

During freeze drying, tissues are placed in what temp

Quenching

Rapid freezing

Desiccation

Removal of ice water mo,ecules

Sublimation

Exposing tissues to a higher temp of -40

Freeze subsitution

process of dehydration

low enough temperature

• prevent ice crystals

• circumvent damage caused by ambient-temperature dehydration

Rossman’s formula

1% acetone

Tissues during freeze subs is fixed using

Absolute alcohok

Freeze subs specimens are dehydrated in what

Microwave

Used in rapid tissue processing to decrease TAT

-45 mins

Processing time for microwave inclfixation

Ethanol

Dehydration in microwave is done using

Isopropanol

What is used in clearing in a microwave

used to dehydrate, clear, and infiltrate tissue samples

fixation is already done prior to processing in the microwave oven

processing schedules are dependent on the tissue thickness

Autotechnicon

large volume of tissue to be processed

More convenient, more efficient

Automatic tissue processing machine

Autotechnicon

transfer the tissue in different fluid for a specified time in a desired environment

Tissue transfer processor (Dip and dunk)

Fluid transfer processor ( enclosed)

Two types of autotechnicon