It consists of examining a tissue section stained with hematoxylin-eosin or toluidine blue under a photonic microscope, which can be done in less than 30 minutes by freezing the tissue sample. It is used in dermatological surgery to quickly determine the status of surgical margins (in sano or tumor) during the excision of malignant skin tumors, particularly during Mohs micrographic surgery. In cases of suspected toxic epidermal necrolysis (TEN) and acute staphylococcal scalded skin syndrome (SSSS), where diagnosis is urgent, an extemporaneous examination of a fragment of detached epidermis can be performed to complete the clinical diagnosis. A fragment of detached epidermis is collected by friction and kept in a moist compress until it can be placed in the cryostat to be frozen and cut immediately. Histological analysis of the section allows the degree of epidermal necrosis to be determined. Necrosis of part or all of the epidermis is indicative of NET. Conversely, if the material collected is only from the stratum corneum, the examination is indicative of SSSS.
Made with Bullet