๐ ็ธฝ็ฎ้ ๏ฝ ๐ ่ฑๆๅๆ๏ผๆฌ็ฏ๏ผ ๏ฝ ๐ ๅฎๆด็ฟป่ญฏ ๏ฝ โญ ็ฒพ่ฏ็ญ่จ
Tissue flattening
Tissue flattening
Since the specimen will be embedded horizontally for sectioning, the tissue must be flattened. For specimens that are beveled at an angle less than 45 degrees, or come from anatomic sites characterized by a thick dermis, the technician may place additional relaxing incisions in the specimen to facilitate the flattening of the section so that the plane of sectioning for the undersurface of the specimen is in the same plane as the epidermal margin. These incisions should be superficial enough to allow the tissue to flatten, but should not extend deep enough to cut the marginal surface of the specimen. Overly deep relaxing incisions may disrupt the orientation and the continuity of the margin and can introduce floaters by forcing tissue at the surface down to the base, producing a false-positive margin.
If there is inadequate relaxation of the tissue, peripheral margins may not be teased down effectively, which results in missing epidermis on the slides. In areas with thin skin, such as the eyelid, the skin may fold easily before embedding, resulting in slides that are cut tangentially and are therefore difficult to interpret.