Cryomikrotomi

Cryomikrotomi, or cryomicrotomy, is a laboratory technique and the instrument used to cut ultra-thin frozen tissue sections for microscopic examination. The cryomicrotome operates inside a cryostat, a temperature-controlled chamber that keeps tissue frozen and guides a microtome knife to produce sections suitable for mounting on slides.

Applications include rapid intraoperative diagnosis during surgery, diagnostic pathology, and research. Frozen sections prepared by cryomicrotomy are often used for quick hematoxylin and eosin staining and can be subjected to rapid immunohistochemical procedures, providing timely information while the patient is under anesthesia. Cryosections are also employed in studies where preserving certain antigens or lipids is important, though they may exhibit freezing artifacts.

Procedure overview: a specimen is trimmed and sometimes embedded in a frozen medium such as OCT, then rapidly frozen in the cryostat. Thin sections, typically a few micrometers thick, are cut with the microtome knife, mounted on glass slides, and fixed briefly for staining. The resulting slides can yield prompt diagnostic or experimental results, though with morphology that may be less sharp than paraffin-embedded sections.

Equipment and components: a cryostat-equipped microtome, temperature control, a freezing stage, a specimen holder, and a glass slide mounting system. Optional accessories support rapid staining or immunohistochemical workflows.

Advantages and limitations: cryomicrotomy provides fast results and preserves some molecular features but can introduce freezing artifacts and yield lower morphological detail compared with paraffin sections. It requires careful handling due to cryogenic hazards and is operator dependent.

History: cryomicrotomy emerged in the mid-20th century as a means to obtain quick tissue diagnoses and remains standard for intraoperative consultation and certain research applications.