The corns usually do not have black spots, but if they do have black spots, they may be plantar warts. Plantar warts are caused by the infection of human papilloma virus, resulting in local keratosis, accompanied by local capillary hyperplasia, hyperplasia of blood vessels necrosis and the formation of local black spots. Chicken eye is due to wear high heels or wear crowded footwear, resulting in friction parts are squeezed to lead to the soles of the foot parts of the stratum corneum thickening or hyperplasia, at first will be relatively small, slowly will become bigger and harder, generally will not appear black spots. When corns appear, it is recommended to treat them under the guidance of a doctor. Commonly used topical medications such as corns cream, whose main ingredients are salicylic acid and phenol, mixed according to a certain ratio. Physical therapy can also be applied, which is suitable for corns with more severe symptoms or deeper into the skin, and commonly used methods include laser, freezing, electrocautery and so on. In addition, in the process of treating corns, attention should also be paid to removing the conditions for the formation of corns, avoiding repeated friction or extrusion of the local skin, such as wearing softer shoes, and improving walking movements and postures, etc., which are very helpful for the treatment of corns.