Normal epidermal and keratin layers

Partial Erosion of Keratin layers with underlying epidermis unaffected. Papillary & reticular dermal collagen layers are without histopathologic change.

Section of skin following addition of glycolic acid reveal no additional histopathologic change.

Epidermal & superficial dermal necrosis to a depth of 0.5mm with associated mild superficial/perivascular inflammation.

Necrosis & acute inflammatory cells

Necrosis of epidermis/superficial dermis.