Instrumentation Flashcards
TYPES OF MICROTOME
SRRFUC
Rotary microtome
Sliding microtome
Rocking microtome
Freezing microtome
Cryostat
Ultrathin microtome
Used for cutting semi-thin to thin sections of paraffin wax (3-5um).
The operation of the microtome is based upon the rotary action of a hand wheel activating the advancement of a block towards a rigidly held knife. The block moves up and down in a vertical plane in relation to the knife and therefore it cuts flat sections.
Rotary Microtome
MOST DANGEROUS
For cutting large blocks of paraffin and resin embedded material including whole organs.
The blade is bigger and is the one moving rather than the tissue blocks.
Sliding Microtome
Inventor: Sir Horace Darwin (1851-1928). Son of Charles Darwin.
• The razor of this microtome is fixed and the specimen to be sliced for microscopic examination passes up and down in an arc of a circle across the razor in a rocking motion.
Rocking Microtome
Cutting thin to semi-thin (about 8-12um) sections of fresh, frozen tissue.
Liquid carbon dioxide from a cylinder or a low temperature recirculating coolant.
The knife is moved while the tissue block remains static.
Freezing Microtome
• For cutting sections of frozen tissue
(STAT).
Contains rotary microtome inside.
Sections as thin as 1 micron are possible.
Temperature. (-15 to -30C) to allow the hardening of the tissue section.
Cryostat
Prepare ultrathin sections for light and electron microscopy.
Knives are usually made from glass, diamond or sapphire.
Block is brought to the knife edge under microscopic control.
Ultrathin Microtome
EQUIPMENT AND APPARATUS
AACE
GMMM
PPPPRS
Here are the items arranged in alphabetical order:
- Automated stainers
- Automated tissue processor
- Cryostat
- Embedding center
- Gross table
- Microscope
- Microtome
- Microwave oven
- Paraffin oven
- Paraffin wax bath
- Paraffin wax dispenser
- Paper boat
- Refrigerator
- Slide dryers
In________, diagnosis of diseases is done by examining the stained morphologic cellular details of the specimen submitted and processed in the laboratory
histopathology
The earliest form of microtomy was the freehand sectioning of fresh or fixed material using a ______
sharp razor
This type of microtome is generally used for cutting semi-thin to thin sections of paraffin wax embedded material for light microscopy.
Rotary microtome
Rotary microtome
Paraffin embedded tissues are normally cut between______
3 to 5 µm.
The operation of the microtome is based upon the rotary action of a hand wheel activating the advancement of a block towards a rigidly held knife.
The block moves up and down in a vertical plane in relation to the knife and therefore it cuts flat sections.
Rotary microtome
These are designed for cutting large blocks of paraffin and resin embedded material including whole organs, for light microscopy.
Sliding microtome
The knife holding clamps allow the knife to be offset to one direction, a major advantage when sectioning large, hard blocks.
Sliding microtome
They are not suitable for cutting very hard resins such as araldite because of the risk of vibration
Sliding microtome
• The razor of this microtome is fixed and the specimen to be sliced for microscopic examination passes up and down in an arc of a circle across the razor in a rocking motion.
Rocking microtome
Fixed on to a table, the ribbons of specimen fell to the desk top then were cut and mounted on to slides.
Rocking microtome
The rocking microtome was invented by______ (1851-1928), the son of_____
Sir Horace Darwin
Charles Darwin
• This form of microtome is used for cutting thin to semi-thin (about 8-12µm) sections of fresh, frozen tissue.
Freezing Microtome
It is equipped with a stage upon which tissue can be quickly frozen using either liquid carbon dioxide, from a cylinder, or a low temperature recirculating coolant.
Some cooling systems also allow the knife to be cooled at the same time.
Freezing microtome
The cutting action of the______ differs from those described previously as in this case the knife is moved while the tissue block remains static.
Consistent, high quality, thin sections are very difficult to obtain with this type of microtome.
freezing microtome
Freezing Microtome • This form of microtome is used for cutting thin to semi-thin (about_____) sections of fresh, frozen tissue.
8-12µm
is primarily used for cutting sections of frozen tissue.
It commonly consists of a microtome contained within a refrigerated chamber, the temperature of which can be maintained at a preset level.
cryostat
The cryostat usually contains a ____ microtome although some portable units utilize a ____ microtome.
Rotary
Rocking
Cryostat
With the block, blockholder and knife all at the same temperature and all other conditions for cutting the material optimal, sections as thin as_____ are possible.
1 micron
• It is used to prepare ultrathin sections for light and electron microscopy.
Very small samples of tissue are usually embedded in hard resin before cutting.
Ultramicrotome
The cutting stroke is motor driven to provide a regular, smooth motion for sections of even thickness and constant reproducibility.
Ultra microtome
The block is brought to the knife edge under microscopic control and as each section is cut it is floated on to a water bath adjacent to the knife edge.
Ultramicrotome
Ultramicrotome
Knives are usually made from
glass
diamond
sapphire
These are used for floating the paraffin ribbon.
FLOTATION BATH OR WATER BATH
Temperature depends on a degree of the personal preference of the microtomist, but it is recommended to maintain a temperature of _____degrees below the melting point of the paraffin used during embedding.
Floatation bath
5 to 10
These are used for drying the water that is collected during the sectioning of tissue section.
Slide dryers
The temperature used is between 5 to 10 degrees above the melting point of the paraffin.
Slide dryer
Slides are left to dry for approximately_____ minutes, after they have been appropriately drained.
Not doing so can cause the bubbling under the tissue sections.
Overheating slides may cause uneven staining as well as artifacts.
Slide dryer
15-20
The______ is used to heat and speed some procedures. Some special stains techniques are performed in the microwave oven.
_____ induced epitope retrieval for Immunohistochemistry is done in some occasions in the microwave oven
microwave oven
Heat
Linear types transfer slides from one container to the next container with the same time allowed in each container.
Automated strainers
Revolving types are similar to the linear stainer and the time allowed in each can be varied.
Robotic ones are flexible with computerized programming that allows the continuous loading and use of the same solutions at different timing.
Automated strainers
• It is a complete system designed for embedding tissue in paraffin.
It provides a controlled heated environment (paraffin is kept at 2 - 4ºC above its melting point) for the processed cassettes and eliminates xylene contamination
EMBEDDING CENTERS
Maintains the paraffin wax in liquid form and aids in dispensing of wax into molds or ca
PARAFFIN WAX DISPENSER
