Nipple protrusion

Inverted nipple is a relatively common breast deformity in women, with an incidence rate of 1% to 2%. The level of nipple inversion varies from person to person. In mild cases, it only manifests as varying degrees of nipple flatness or retraction, and after excessive tension, the nipple may bulge or be squeezed. In severe cases, the nipple is completely sunken into the nipple and cannot be pulled out, resembling a dead volcano, and is often accompanied by secretions or odor.

Causes:

The causes of inverted nipple are divided into two types: congenital and acquired, and most of them are congenital. The nipple consists of the openings of 15 to 20 mammary glands, which are surrounded by smooth muscles that widen the nipple. The main cause of congenital nipple inverted is the proliferation disorder of mesoderm during puberty of nipple embryo, which is mainly manifested as incomplete development of nipple, nipple smooth muscle and mammary gland tube, resulting in the inability of mammary gland tube to tuberculosis.

The contracted cord and the surrounding smooth muscle and fibrous connective tissue contracture cause the lack of supporting tissue under the nipple, and the mammary gland stretches inward, resulting in an unclear nipple protrusion or a retracted nipple. Acquired nipple inversion is caused by the expansion of the nipple by pathological tissue in the breast. The most common cause is breast cancer, followed by infection, trauma and expansion of scars after breast surgery. It is occasionally seen in loose and large breasts.

Clinical medicine classification:

There are many ways to classify nipple inversion. The most common classification method used in textbooks around the world is to divide nipple inversion into three types based on the degree of intensity. Type I (mild): Part of the nipple is inverted, the nipple neck exists and can be easily squeezed. After squeezing, the nipple size is similar to that of normal people. Type II (mild to moderate): The nipple is completely indented in the nipple, but it can be squeezed out by hand. The nipple is smaller than normal, and most of them have no nipple neck. Type III (moderate to severe): The nipple is completely buried under the nipple, and the inverted nipple cannot be squeezed.