Microtomy Flashcards
Expected output after embedding
Tissue Block
Purpose of Trimming
Even out the edges of tissue block
Ideal shape in trimming
Truncated Pyramid
At least __mm of wax should surround the tissue
2
other term for Microtomy
Sectioning
An indication that your sectioning is correct
Tissue Ribbons
Complete ribbons are picked up and transferred to a flotation bath using what utensils?
camel hair brush
forceps
fingers
Microtome Principle
Spring-balanced or pawl is brought into contact with, and turns the ratchet feed wheel connected to a micrometer screw, which is, in turn rotated, moving the tissue back at a predetermined distance towards the knife for cutting sections at a uniform thickness
Essential parts of a microtome
Block holder
Knife Carrier and Knife
Pawl
Ratchet Feed Wheel
Adjustment Screws
Part of microtome that holds the tissue block
Block Holder
Part of microtome that does the actual cutting or sectioning of the tissues
Knife Carrier and Knife
6 Types of Microtome
Rocking Microtome
Rotary Microtome
Slide Microtome
Freezing Microtome
Cryostat/Cold Microtome
Ultrathin Microtome
Simplest Microtome
Rocking Microtome (Cambridge)
Who invented the Rocking Microtome
Paldwell Trefall (1881)
Tissue thickness for Rocking Microtome
10-12 um
Most common microtome
Rotary Microtome (Minot)
Tissue thickness for Rotary Microtome
3-5 um
Who invented the Rotary Microtome
Minot (1885-1886)
Who developed the Sliding Microtome
Adams (1789)
2 Types of Sliding Microtome
Base-Sledge Microtome
Standard Sliding Microtome
Sliding Microtome:
Electrically driven and ideal for resin-embedded decalcified bone
Base-Sledge Microtome
Sliding Microtome:
Knife is moving; the most dangerous type of microtome because of the exposed moving blade
Standard Sliding Microtome
Recommended microtome for cutting “extremely” hard and rough tissue blocks
Sliding Microtome
Who invented the Freezing Microtome
Quickett (1848)
Freezing agent used in Freezing Microtome
Carbon Dioxide
Microtome used to cut undehydrated tissues in a frozen state
Freezing Microtome
Microtome ideal for fresh tissues that did not undergo fixation down infiltration
Freezing Microtome
Microtome used for rapid preparation of urgent tissue biopsies for intraoperative diagnosis
Cryostat
Cryostat Chamber temp
-5 to -30C (average fo 20C)
Part of cryostat capable of freezing fresh tissue within 2-3 mins
Thermostat
Tissue size for Cryostat
4 um
Tissue size for Ultrathin Microscope
0.5 um
Ultrathin Microtome Medium
Plastic
Microtome for electron microscopy and tissues fixed with osmic acid
Ultrathin Microtome
What knife does Ultrathin Microtome use
Diamond Knife
Tissue size of paraffin sections
4-6 um
Tissue size of Celloidin sections
10-15 um
Celloidin block and sections are kept moist using what
70% Alcohol
3 Knives in Microtomes
Plane-Concave
Biconcave
Plaen-Wedge
Plane Concave Knife length
25mm
Biconcave Knife length
120mm
Plane-Wedge knife length
100mm
Microtome knife where one side is flat and the other side is concave
Plance-Concave
Microtome Knife where both sides are concave
Biconcave
Microtome Knife where both sides are straight
Plane-Wedge
Embedding medium for Plane-Concave knives that are less concave
Celloidin
Embedding medium for Plane-Concave knives that are more concave
Paraffin
Embedding Medium for Biconcave and Plane-Wedge knives
Paraffin
Microtomes that use plane-concave knives that are less concave
Sliding Microtome
Microtomes that use plane-concave knives that are more concave
Base Sledge or Rotary Microtome
Microtomes that use biconcave knives
Rotary Microtome
Microtomes that use plane-wedge knives
Base-Sledge Microtome
Microtome knife that is coated with polytetrafluroethylene
Disposable Blade
Microtome knife that is for partially calcified materials, paraffin, and frozen sections
Safety Razor Blade
Bevel Angle
27 to 32 degrees
Cutting Angle
14 degrees
Most important knife angle
Clearing Angle
Clearing Angle
5 to 10 degrees
Heel to Toe sharpening
Honing
Toe to Heel
Stropping
Honing vs Stropping:
Removing of Gross nicks
Honing
Honing vs Stropping:
Removal of Burr/Irregularities
Stropping
Sharpening method that aims to acquire an even edge
Honing
Final polishing of the knife edge
Stropping
Most common Hone
Belgium Yellow
Hone that has a more polishing effect
Arkansas
Hone used for badly nicked knives
Fine Carborundum
Lubricants for Honing
Soapy water
Mineral Oil
Clove Oil
Xylene
Liquid Paraffin
Knife Sharpener used for grinding and removing nicks
Flat Glass plate (w/ finely powdered aluminum oxide)
Knife Sharpener for final polishing
Diamantine
In Stropping, instead of hones, what is used?
Paddle Strop
Enumerate 5 adhesives
Mayer’s Egg Albumin
Dried Albumin
Starch Paste
Sodium Silicate
Resin
Most common adhesive
Mayer’s Egg Albumin
Main Adhesive in Mayer’s Egg Albumin
Egg white
Increases viscosity and prevents drying in Mayer’s Egg Albumin
Glycerol
Prevents mold formation in Mayer’s Egg Albumin
Thymol Cyrstals
Floatation water bath temp
45 to 50 C (5-10C below melting point)
Inside of Floatation bath is colored using what
Enamel Black
Recommend number of tissue sections for Floatation
3 to 5
Slide Dryer temp
5 to 10 C above melting point
Used to store the mounted section during the drying
Metal Racks (w/ 25-slide divisions)