Histological indicators of cutaneous lesions caused by electrocution, flame burn and impact abrasion

Cutaneous electrocution marks are the key indicator that aid forensic pathologists in establishing electrocution as the cause of death, especially when crime scene and internal autopsy findings do not provide significant information. The gross findings of electrocution mark are often confused with impact abrasion and the burns produced by high voltage flash are often indistinguishable with flame burns. The present study aims to identify cutaneous light microscopic histological indicators, which are peculiar to electrocution marks, burns and impact abrasions. Cutaneous tissue samples from injury sites and healthy areas were collected from 45 autopsy cases and examined under light microscope. The histological changes observed were intra-epidermal separation of cells, sub-epidermal separation, coagulative necrosis in the epidermis and dermis, epidermal and dermal cell nuclear elongation and streaming, pyknotic tightly packed epidermal nuclei, dark staining of epidermal nuclei, homogenization of dermal collagen, and vascular dilatation, congestion, hemorrhage and thrombosis. The study revealed that certain histological changes are helpful in differentiating electrocution mark from other types of injuries, which present themselves in various types morphologically and thus facilitate correct diagnosis during autopsy. Pyknotic and tightly packed epidermal nuclei was found characteristic of electrocution mark produced by high voltage current.