Mild cases of pectus excavatum in children are usually caused by malnutrition, such as vitamin D deficiency and rickets caused by calcium deficiency, which can be treated with calcium gluconate and vitamin D. More sunbathing is required, and mild cases of pectus excavatum can be corrected on their own during later growth and development. If the pheochromocystis develops further, after it is older than three years old, it can also be treated with pheochromocystis support, which can gradually restore the normal shape of the thorax by compressing the lower part of the sternum that is lifted upward.