Cryotome

Cryotome

A cryotomeis a specialized instrument used in the field of histology and pathology for cutting extremely thin sections of biological tissue. These sections are typically used for microscopic examination and analysis. The cryotome is an essential tool in medical laboratories, particularly for procedures that require rapid diagnosis, such as during surgery.

Principle of Operation

The cryotome operates on the principle of freezing tissue samples to a temperature that makes them firm enough to be sliced into thin sections. This is achieved by embedding the tissue in a medium such as OCT compound (Optimal Cutting Temperature compound) and then rapidly freezing it using a cryogenic substance, often liquid nitrogen or a refrigerated chamber.

Once the tissue is adequately frozen, it is mounted on a specimen holder within the cryotome. The cryotome is equipped with a microtome blade that slices the tissue into sections, typically ranging from 5 to 10 micrometers in thickness. These sections are then collected on glass slides for staining and examination under a microscope.

Applications

Cryotomes are widely used in various medical and research applications, including:

• Intraoperative Consultation: During surgical procedures, pathologists use cryotomes to provide rapid diagnostic information. This is crucial for determining the nature of a lesion and guiding surgical decisions.
• Immunohistochemistry: Cryotome sections are often used in immunohistochemical staining to detect specific antigens in tissues, aiding in the diagnosis of diseases such as cancer.
• Research: In research settings, cryotomes are used to prepare tissue sections for various types of analysis, including fluorescence microscopy and in situ hybridization.

Advantages and Limitations

Advantages

• Speed: Cryotomes allow for rapid preparation of tissue sections, which is essential for time-sensitive diagnostic procedures.
• Preservation of Antigenicity: The freezing process preserves the antigenicity of proteins, making cryotome sections ideal for immunohistochemical studies.

Limitations

• Artifact Formation: The freezing process can introduce artifacts, such as ice crystal formation, which may affect the quality of the tissue sections.
• Limited Tissue Types: Some tissues may not freeze well or may be difficult to section, limiting the use of cryotomes in certain cases.

Maintenance and Safety

Proper maintenance of a cryotome is essential to ensure its accuracy and longevity. Regular cleaning and blade replacement are necessary to maintain optimal performance. Safety precautions must be observed when handling cryogenic substances and sharp blades to prevent injury.

Also see

• Microtome
• Histology
• Pathology
• Immunohistochemistry