Search results
Results from the WOW.Com Content Network
In the tissue microarray technique, a hollow needle is used to remove tissue cores as small as 0.6 mm in diameter from regions of interest in paraffin-embedded tissues such as clinical biopsies or tumor samples. These tissue cores are then inserted in a recipient paraffin block in a precisely spaced, array pattern.
Frozen tissue cores with 2 mm diameter from the regions of interest are removed from frozen tissue OCT blocks at different freezing temperature since each tissue type has their own temperature preference at frozen stage. Then all the frozen tissue cores are inserted in a recipient OCT frozen block in a precisely spaced, array pattern.
The microtome device that cold cuts thin blocks of frozen tissue is called a cryotome. [2] The quality of the slides produced by frozen section is of lower quality than formalin fixed paraffin embedded tissue processing. While diagnosis can be rendered in many cases, fixed tissue processing is preferred in many conditions for more accurate ...
The laser microtome has the ability to slice almost every tissue in its native state. Depending on the material being processed, slice thicknesses of 10 to 100 μm are feasible. Sectioning intervals can be classified mainly into either: Serial sectioning: obtaining a continuous ribbon of sections from a paraffin block and using all for slides.
In a histology or pathology laboratory, paraffin wax is used to impregnate tissue prior to sectioning thin samples. Water is removed from the tissue through ascending strengths of alcohol (75% to absolute), and then the alcohol is cleared in an organic solvent such as xylene. The tissue is then placed in paraffin wax for several hours, then set ...
The substance used to embed tissue is embedding media, which is chosen depends on the category of the microscope, category of the micro tome, and category of tissue. [23] Paraffin wax, whose melting point is from 56 to 62°C, is commonly used for embedding. [22] Tissue processing - Tissue sections on slides are stained on an automated stainer
In most histology, or histopathology laboratories the dehydration, clearing, and wax infiltration are carried out in tissue processors which automate this process. [13] Once infiltrated in paraffin, tissues are oriented in molds which are filled with wax; once positioned, the wax is cooled, solidifying the block and tissue. [13] [12]
The classical tools for studying tissues are the paraffin block in which tissue is embedded and then sectioned, the histological stain, and the optical microscope. Developments in electron microscopy , immunofluorescence , and the use of frozen tissue-sections have enhanced the detail that can be observed in tissues.