Introduction of Cryostat Flashcards
What is a cryostat and what is inside?
What type of microtome has the cryostat replaced mostly?
what are antiroll devices designed for?
Cryostat is a refrigerated chamber
with a rotary* microtome inside
Has replaced most of the freezing
microtomes
Anti roll devices are designed for
specific blade types (high or low
profile)
What type of tilt is very important?
what is the optimal angle between the centerline of the blade and face block?
What will too little blade tilt cause?
What will too much blade tilt cause?
Blade edge tilt is VERY important
30 degree between centerline of the
blade and face block is optimal
Too little blade tilt will have varying
section thickness
Too much blade tilt will cause scraped
sections
What type of environment is very important when using the cryostat?
What is the working temperature environment based on?
What could be the cause of splitting sections?
What does clumping sections at the blade indicate?
At what temperature are most cryostats maintained at?
Working temperature environment is
very important
This is based on the lipid and water
content of the tissue being sectioned
Splitting sections could be too cold
Clumping sections at the blade
indicates the tissue might be too warm
Most cryostats are maintained at -20
degrees Celsius
What type of tissues section better at warmer temperatures?
What type of tissues section better at much colder temperatures?
Brain, liver, spleen, lymph node, and
endometrial scrapings section better
at warmer temperatures
Tissue with a high lipid content section
better at much colder temperatures (adipose)
Slow freezing allows water to form ice
crystal artifact, how can we avoid this?
This artifact appears as hole in the
section, also known as?
Why should tissues not be left in the cryostat for storage?
What are freezers with -70 degrees Celsius used for?
It can be avoided by…
Known as “Freeze Thaw
Artifact” or “Swiss Cheese”
Tissue should not be kept in the
cryostat for storage as this will
dehydrate it
Freezers with -70 degree Celsius are
for long term storage of frozen specimens
Why do we want to freeze tissues quickly?
You want to freeze tissue quickly so that
water does not have time to form ice
crystals and remains in a form that
does not expand
The cryostat can be potentially
hazardous, why?
What should be done after using the cryostat?
How is the cryostat decontaminated?
The cryostat can be potentially
hazardous because…. biological hazard
Steps to decontaminate the cryostat
should be taken after use
Steps to decontaminate the cryostat includes:
1.) Using damp gauze with alcohol OR
2.) Using the UV light present in some newer
cryostats
!!!!! Removing ALL tissue scrapings !!!!!!!
What is essential for good cryostat operation?
What does maintenance include? (4 things)
Routine maintenance is essential for
good cryostat operation
1.) Must be defrosted, and cleaned
frequently
2.) Keeping cryostat dry before freezing is
important so water doesn’t freeze
3.)Silicone lubricant must be special for
cryostats as to not harden at cooler
temps
4.) Coils must stay dust free, and cleaning
them is important for routine
maintenance to avoid instrument deterioration
Who gives the cryostat decontamination recommendations?
What does CAP recommend?
CAP
CAP recommendations include
decontaminating once a week and use
of liquids to destroy HIV, tuberculosis,
and other dangerous diseases
