What Is the Internal Mammary Artery?

A pair of arterial trunks on the inside of the anterior chest wall. It starts from the inferior wall of the subclavian artery and enters the thoracic cavity downwards, and the inner surface of the thoracic wall drops approximately 1 cm away from the outer edge of the sternum. The pectoralis thoracic rib angle continues as the superior abdominal wall artery and descends between the rectus abdominis sheath and rectus abdominis. , To the vicinity of the umbilicus and anastomosis of the abdominal wall. In addition, phrenic arteries and pericardial iliac arteries are also emitted. Internal thoracic arteries are distributed in front of intercostal muscles, diaphragm, rectus abdominis, breasts, pericardium, and part of thoracic and peritoneum.

A pair of arterial trunks on the inside of the anterior chest wall. It starts from the inferior wall of the subclavian artery and enters the thoracic cavity downwards, and the inner surface of the thoracic wall drops approximately 1 cm away from the outer edge of the sternum. The pectoralis thoracic rib angle continues as the superior abdominal wall artery and descends between the rectus abdominis sheath and rectus abdominis. , To the vicinity of the umbilicus and anastomosis of the abdominal wall. In addition, phrenic arteries and pericardial iliac arteries are also emitted. Internal thoracic arteries are distributed in front of intercostal muscles, diaphragm, rectus abdominis, breasts, pericardium, and part of thoracic and peritoneum.

Chinese name

Internal thoracic artery

Foreign name

internal thoracic artery

nickname

Internal mammary artery

Send out

Start of first vertebral artery of the subclavian artery

Points for

Myoiliac artery and superior abdominal wall artery

1 Internal thoracic artery 1. Anatomy of internal thoracic artery:

Opposite the start of the vertebral artery, it is emitted from the lower wall of the first segment of the subclavian artery, travels down the inner edge of the anterior scalene muscle, enters the thorax via the medial half of the clavicle and the front of the pleura, and follows the The inner surface, about 1.25 cm from the lateral edge of the sternum, descends, penetrates into the rectus abdominis sheath of the anterior abdominal wall, moves to the superior abdominal wall artery, and coincides with the inferior abdominal wall artery. The internal thoracic arteries branch out along the intercostal branch, perforating branch, pericardial iliac artery, and myoiliac artery, and are mainly distributed in the anterior chest wall, breast pericardium, septum, pleura and anterior abdominal wall, and peritoneum.

2 Internal thoracic artery 2. Clinical anatomy of internal thoracic artery:

The perforating branch of the internal thoracic artery exits from the lateral edge of the sternum, runs in the superficial layer of the subcutaneous tissue toward the nipple, and forms an anastomosis with the branches of the lateral thoracic artery that also runs in the superficial layer of the subcutaneous tissue around the areola. In the intercostal branch of the internal thoracic artery, the second intercostal space is still relatively large. The branches of the lateral thoracic arteries are also thicker than the branches that lie above the areola.

3 Internal Thoracic Artery 3. Blood Supply to Internal Breast:

Some scholars found that during the travel of the internal thoracic artery, the medial and lateral branches were issued at the 2nd, 3rd, 4th, 5th, and 6th intercostals, the medial branches traveled forward and backward, and the lateral branches were arranged in three layers from deep to shallow: The deepest layer is the anterior intercostal artery; the middle layer is composed of the muscular branches supplying the pectoralis major muscle; the superficial layer is composed of the cutaneous branches, which are originated from the main internal rib cage artery or from the anterior intercostal artery or from the pectoral muscle branch Work together. Therefore, no branch directly into the breast was found.

Some scholars believe that after the internal mammary artery penetrates from the sternum, large branches enter the human breast, and some small branches supply the upper skin, and the last part surrounds the skin piercing branch of the nipple areola and the lateral thoracic artery branch and intercostal artery. Form an anastomosis. Some scholars have found that the internal mammary artery travels in the subcutaneous tissue that is about 0.5 to 1.5 cm deep from the skin surface at the edge of the breast. During the process, small branches are distributed to the glands and skin. When approaching the nipple areola, it is related to the branches and ribs of the lateral thoracic artery. The skin perforating branch of the interartery forms different types of nipples around the blood vessels around the areola. One scholar believes that the internal thoracic artery is divided into two shallow and deep branches at the edge of the gland. The shallow branch runs deep in the subcutaneous fat layer, and the deep branch travels outward from the posterior space of the mammary gland and enters the gland obliquely toward the nipple areola. The descriptions about which of the six intercostal perforating branches on the internal thoracic artery are the thickest are also inconsistent. The results in this article are similar to those of some scholars. It is found that the second intercostal perforator is the thickest in most specimens, and the subcutaneous tissue is superficially toward the nipple and areola. The area around the areola and the lateral thoracic artery branches and intercostal artery are perforated. The peripheral vessels of the branch form an anastomosis, and the perforating branch of the internal thoracic artery does not directly enter the larger branch vessels of the breast.