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Phase contrast microscopy for identifying epidermal margins in unstained cryosections for Mohs micrographic surgery
1Marshall Dermatology Research Laboratories, Department of Dermatology, University of Iowa College of Medicine, Iowa City.
Background:
Mohs fresh tissue micrographic surgery has been accepted as the most reliable therapeutic modality for the eradication of recurrent cutaneous malignancies or those skin cancers that are difficult to treat otherwise.
Objective:
We have developed a method to ascertain the presence of the epidermis and other edges in the tissue sections before staining the cryosections and microscopically searching them for cancer cells.
Methods:
Our method for screening the cryosections for the epidermis can be done quickly and easily using relatively inexpensive phase contrast optics.
Results:
Use of this method allows easy visualization of freshly cut cryosections, especially the presence of the epidermis and other edges of the tissue, in just a matter of seconds instead of a half hour to stain and recut the sections.
Conclusions:
Phase contrast microscopy and/or dark field illumination are instrumental in screening unstained cryosections for the presence of the tissue borders, especially the epidermis, before they are stained with hematoxylin and eosin. This method saves a great deal of time and effort both for the surgeon and the patient.
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