Histological examination involves obtaining a tissue sample through biopsy or during surgical procedures. The sample is then stained and examined under a microscope. Common stains used in DDD diagnosis include Hematoxylin and Eosin (H&E) for general tissue structure, Safranin O for detecting proteoglycans, and Masson's Trichrome for collagen fibers. Immunohistochemical techniques may also be used to identify specific proteins and markers of inflammation and cell death.
