THE MAMMA OR BREAST. 



Suspensory band 



Pectoral muscle 



directions in which the glandular tissue is prolonged, but it may extend farther 

 than usual in any direction; hence the wide incisions made in cases of carcinoma. 



According to H. J. Stiles (Ed. Med. Journ., 1892, p. 1099), the secreting 

 structure may extend posteriorly into the retromammary tissue between the layers 

 of the pectoral fascia. Anteriorly it is prolonged with the fibrous tissue (ligaments 

 of Cooper) almost to the skin. 



The nipple, located below and to the inner side of the centre of the gland, 

 has connected with it some circular and longitudinal unstriped muscular fibres. 

 The longitudinal ones are attached to the lactiferous ducts and serve to retract 

 the nipple, the circular ones to erect it. Surrounding the nipple is the areola. 

 It is pink in the virgin and about 2.5 cm. in diameter. After pregnancy its hue 

 becomes brownish. The tubercles of Montgomery are the numerous elevations 

 found on the areola. They are more or less 

 modified sebaceous glands and enlarge during 

 pregnancy. As they secrete a milky fluid, they 

 are often regarded as accessory milk ducts. 

 There is no fat in the nipple or areola. 



The fibrous structure of the gland 

 envelops the adipose and glandular tissue. 

 It is simply a continuation of the fibrous septa 

 of the superficial fascia. These septa are at- 

 tached to the skin above, envelop and pass 

 between the fatty and glandular lobules, and 

 form a thin covering for the under surface of 

 the gland. The breast is sometimes spoken of 

 as having a capsule, but that simply refers to 

 the fibrous tissue just described. This fibrous 

 tissue follows largely the ducts, hence when 

 affected with carcinoma it contracts and draws 

 the nipple in. This forms the retracted nipple 

 of that disease. The fibres that go to the skin 

 have been named the ligaments of Cooper. 

 The fibrous tissue forms a net-work in the 

 meshes of which are packed the glandular 

 structure and fat-lobules. It is this which 

 gives the firmness and shape to the virgin 

 breast. In lactation, the fibrous tissue softens 

 and stretches to accommodate the increase in 

 the glandular structure and this, with the loss 

 of fat, causes the breast to become lax and 

 pendulous. In palpating a normal breast be- 

 tween the fingers and the thumb, this firm- 

 ness may feel like a foreign growth; hence 

 this method of examination is not to be relied 



A better way is to have the patient re- 



Gland- 

 tissue 



Fat 



Fascial envel 



on. 



FIG. 206. Sagittal section of mamma of young 

 woman who had never borne children; hardened 

 in formalin. (Piersol.) 



cline, and lay the fingers flat on the breast, 

 compressing it on the chest-wall beneath. 

 This flattens the glandular structure and any mass can be more surely detected. 



The fibrous tissue between the glandular structure and the pectoralis beneath 

 is quite thin and loose, with large spaces in it which have been called the sub- 

 mammary bursa. Pus readily spreads in this loose submammary tissue, but in the 

 gland itself only with difficulty. 



Blood Supply. The breast is supplied with blood. from above by \hzpectoral 

 branch of the acromial thoracic artery, which leaves the axillary artery at the inner 

 border of the pectoralis minor muscle. The pectoral branch descends between the 

 pectoralis major and minor and anastomoses with the intercostals and long thoracic. 

 It sends branches through the pectoralis major muscle, and in carcinoma of the gland 

 it may be seen much enlarged running downward on the chest-wall beneath the 

 muscle. From the inner side come \he perforating branches of the internal mammary 



