Frozen Section Technique & Cryostat
Introduction
Dr. Louis B Wilson described the procedure of the frozen section.
The frozen section technique is a procedure carried out in the histopathology lab to perform a rapid microscopic analysis of a specimen. It is also used to analyze tissue for cancer diagnosis. It’s a significant procedure used in Enzyme-Histochemistry, Immuno-Histochemistry, detection of lipids, etc. The technical name for this procedure is cryo-section. The instrument for cryo-section is the cryostat which is essentially a microtome inside a freezer. The microtome is capable of slicing tissue sections as thin as 1 um.
Specimen collection
• The surgeon will take a biopsy of the tumor and send it to the histopathology lab.
• The histo-technologist quickly performs the frozen section technique by cryostat microtome.
• The histo-pathologist identifies the pathology and makes a diagnosis.
A Cryostat is a microtome machine used to cut tissue sections at low temperatures( typically around -15°C to -30°C).
Types of Cryostat:
1) Rotary Cryostat-(Single Compressor & Double Compressor)
2) Motorized Cryostat-(Single Compressor & Double Compressor)
Working Process
• First, switch ON the cryostat 10 to 15 minutes before use to maintain the temperature.
• Now, set the temperature according to the type of tissue by using the manual book of the cryostat.
• After maintaining the temperature start the process of the frozen section technique.
Care & Maintenance
- Routinely, after the frozen section
• Always check the levels of the waste in the waste container before and after use. And discard if required.
• Wear protective clothing. A long-sleeved laboratory coat or gown with elasticized wrist bands, rubber gloves, and safety goggles afford the minimum standard of protection.
• Remove the microtomy debris from the cryostat chamber and place it into a fixative, disinfectant, or wet bag for autoclaving.
• Clean the knife and all exposed surfaces and instruments with 70% ethanol.
- Monthly
• Wear protective clothing, same as routine maintenance.
• Turn off the power switch and unplug the cryostat.
• Rinse the cabinet and the microtome with 70% ethanol, then defrost overnight.
• Then place a waste bucket containing 5% sodium hypochlorite below the drain outlet of the cryostat.
• Remove the microtome from the cabinet after defrosting and wash with hot water containing detergent, then rinse in absolute ethanol and allow to dry.
• All sliding parts should be an oil with low-temperature oil.
• Wash the inside of the cabinet with warm water containing detergent.
• Rinse the cabinet with absolute ethanol, then allows drying.
• Replace the microtome when dry, then reconnect the power.
