HISTOPATHOLOGY Flashcards
● Involves different procedures that have been adopted for the preparation of materials and tissue for microscopic
examination
HISTOPATHOLOGIC TECHNIQUES
12 STEPS IN HISTOPATHOLOGIC
TECHNIQUES:
- Numbering
- Fixation
- Dehydration
- Clearing
- Wax impregnation
- Embedding
- Blocking
- Trimming
- Sectioning
10.Staining
11.Mounting
12.Labeling
● Validates if the specimen is adequate or good for tissue processing
● 1st person that will receive the specimen and put it into the container
RECEPTIONIST
Container: contain fixatives
○ Proportional to the size of the specimen
○ Clear
○ Unbreakable
○ Wide mouthed bottle
Specimen source
○ Bilateral organs
○ Miscellaneous
Bilateral organs
Extremities, kidneys, lungs and ovaries
Miscellaneous
Age, sex, ward
Basic information needed:
○ Date and time
○ Name of the patient
○ Specimen number
CAS
■ C - Cytology
specimen
■ A - Anatomical
specimen
■ S - Surgical
specimen
● S-09-2111
● Most critical step in histopathological techniques
FIXATION
preserve the morphology and chemical constituents of the tissue.
Primary aim
protect and harden the specimen for
further handling
Secondary aim
Effects Of Fixatives
- Inhibit bacterial growth and reduce the risk of infections
- Act as mordant or accentuator accelerating the staining process
Involves small tissue or organ
MICROANATOMIC FIXATIVE
● 10% Formol Saline
● 10% Neutral
Buffered
Formalin
MICROANATOMIC FIXATIVE
Involves body fluid or secretion
1. Nuclear Fixatives
2. Cytoplasmic Fixatives
CYTOLOGICAL FIXATIVE
Flemming’s Fluid, Bouin’s Fluid, Heidenhain’s Susa
Nuclear Fixatives
– Kelly’s Fluid, Orth’s
Cytoplasmic Fixatives
Involves tissue containing labile
substances
HISTOCHEMICAL FIXATIVE
- 10% Formol Saline
- Absolute Ethyl Alcohol
- Acetone
HISTOCHEMICAL FIXATIVE
SIMPLE FIXATIVE
Uses only on chemical for fixation
1. Aldehydes
2. Metallic Fixatives
Formaldehyde, Glutaraldehyde
Aldehydes
Mercuric Chloride, Chromate Fixatives, Lead Fixatives
Metallic Fixatives
The use of two or more chemicals for fixation
COMPOUND FIXATIVE
● Utilizing chemical known as dehydrating agents
● Removing of intracellular and extracellular water and fixatives in the tissue
DEHYDRATION
DEHYDRATION Examples:
○ Alcohol - most commonly used
○ Acetone
○ Dioxane
○ Tetrahydrofuran
○ Cellosolve (Ethylene glycol monoethyl ether)
● Removing of dehydrating agents
● Xylene – most commonly used
CLEARING
● Also known as INFILTRATION
● The process whereby the clearing agent is completely removed from the tissue and replace by a medium that will completely fill all the tissue
cavities.
IMPREGNATION
The simplest, most common and best
embedding medium used for routine
tissue processing
PARAFFIN
● Also known as CASTING OR BLOCKING
● The process by which the impregnated tissue is placed into a precisely arrange position in a mold containing medium which is then allowed to solidify
EMBEDDING
FOUR TYPES OF TISSUE IMPREGNATION:
- Paraffin wax
- Celloidin
- Gelatin
- Plastic
● Allows the medium to solidify to produce tissue block
BLOCKING
● Process of removing excess wax after embedding
● Can use knife/blade or heated spatula
TRIMMING
● Also known as CUTTING OR MICROTOMY
● The process by which processed tissue is cut into uniformly thin slices to facilitate studies under microscope
SECTIONING
machine or instrument used for cutting sections of tissue
MICROTOME
Simplest and oldest type of microtome
ROCKING MICROTOME
Used for cutting serial sections of tissue specimen
ROTARY MICROTOME
Most dangerous type of microtome
SLIDING MICROTOME
For urgent surgical biopsies specimen
FREEZING MICROTOME
Permits rapid penetration of tissue biopsies for surgical pathology Also known as COLD MICROTOME
ROTARY MICROTOME
Specimen for electron microscope
ULTRATHIN MICROTOME
● Tissue constituent are demonstrated in sections by direct interaction with dye or staining solution producing
coloration of the active tissue component
STAINING
○ Utilizes micro-anatomical studies of tissue
○ It is a regressive staining method
HEMATOXYLIN AND EOSIN STAINING
● It may be liquid, gum or resinous, soluble in water, alcohol or other solvents and be sealed from the external atmosphere by non-soluble
ringing media
MOUNTING
the solution in which the specimen is
embedded, generally under a cover glass
MOUNTING MEDIUM
LABELING
● Date and time
● Name of the patient
● Specimen Number
● Performed regularly even in pregnant women without undue risk
GYNECOLOGICAL SPECIMEN
GYNECOLOGICAL SPECIMEN
EXAMPLE:
○ Vaginal smear
NON-GYNECOLOGICAL SPECIMEN
EXAMPLE:
○ Respiratory Tract specimens:
■ Sputum
■ Bronchoalveolar lavage (BAL)
Determine the presence of urethral cancer
URINE
