Pigment color in tattoo sections; identification by polarized light.

Abstract

Recently, in studying microscopic sections of tattoos, it was noted that it was impossible to identify the color of the dye or pigment used in the tattooing process. On sections stained with hematoxylin and eosin, as well as on unstained sections, all the pigment appeared dark brown or black. Under a high-power lens, with a strong light source on unstained sections, red dye may show a slight amber tinge. The black dye in stained sections, because of the surrounding pink collagen fibers, will also show this characteristic. Because of these difficulties, it is almost impossible to be certain of the dye color, and the pathologist must refer to the gross specimen in order to identify the pigment. To overcome this problem, stained and unstained tattoo sections were examined under polarized light. This is accomplished by placing a polarized plastic (polarizer) in front of the light source and a second plastic