Infiltration/Impregnation Flashcards
Purpose of infiltration
To remove clearing agent from tissues
To fill cavities and tissue spaces to give firm consistency for easy cutting
Purpose of infiltration
To remove clearing agent from tissues
To fill cavities and tissue spaces to give firm consistency for easy cutting
Infiltration Methods:
- Manual
- Automatic
- Vacuum
Paraffin wax substitute: (4)
- Paraplast
- Bioloid
- Carbowax
- Ester Wax
Infiltration under negative atmospheric pressure inside the oven
Vacuum
Most rapid method as it subject tissues to a very high temperature
that facilitates removal of transition solvents and prolongs life of wax
by preventing solvent contamination
Vacuum
Uses autotechnicon which requires 3-4 changes of wax
Automatic
Temperature range for manual infiltration
55-60°C
Approximate temperature when using manual infiltration
2-5°C higher than the wax melting point
Recommended for bones
Paraplast
Melting point of Paraplast
56-57°C
Substitute for paraffin wax used for eye specimens
Bioloid
Paraffin substitute that is water soluble
Carbowax
What is carbowax?
A polyethylene glycol that has 18 or more carbon atoms
Appears solid at room temperature
Carbowax
Recommended for enzyme histochemistry
Carbowax
Melting point of Ester Wax
46-48°C
Substitute for paraffin wax that requires heavy duty microtome
Ester wax
Recommended for specimens with large and hollow cavities that tends to collapse
Celloidin/Collodion infiltration
A very slow process which involves submerging of tissue in different concentration
Celloidin infiltration
Recommended for whole eye specimens
Dry celloidin
Dry celloidin require the use of what mixture to store blocks
Gilson’s mixture
Celloidin infiltration method for bones, brain, & teeth specimens
Wet celloidin
Wet celloidin require the use of which agent to store blocks?
70-80% alcohol
More preferred than usual celloidin as it produces harder blocks and allows cutting of thinner section
Low Viscosity Nitrocellulose (LVN)
Soluble in equal concentration of ether and alcohol
Low Viscosity Nitrocellulose (LVN)
Has a lower viscosity which causes higher concentration and can
still penetrate tissues rapidly
Low Viscosity Nitrocellulose (LVN)
Disadvantage of Low Viscosity Nitrocellulose (LVN) and its remedy
Tissues have tendency to crack
Remedy: Add plasticizers (Oleum Ricini & Castor oil)
Infiltration method for Enzyme and Histochemical studies
Gelatin infiltration
This is only done when dehydration is to be avoided
Gelatin infiltration
In gelatin infiltration method, this can be used to prevent growth of molds
Phenol
Gilson mixture components
Chloroform + Cedar wood oil
