Accessory breast tissue is a relatively common congenital condition in which abnormal accessory breast tissue is seen in addition to the presence of normal breast tissue. This normal variant can present as a mass anywhere along the course of the embryologic mammary streak (axilla to the inguinal...
Amastia is a rare congenital condition characterised by the absence of breast tissue, nipple and areola. This may occur unilaterally or bilaterally.
During embryological development, breasts first appear as ectoderm ridges during the 6th week of gestation. This ridge grows thicker an...
Amazia is a rare congenital condition defined by the absence of glandular parenchyma in either one or both of the breasts and a normal nipple and areola complex.
This is a very rare entity and the true prevalence is not known. Although there are strict definition criteria, the di...
The anatomy curriculum is one of our curriculum articles and aims to be a collection of articles that represent the core anatomy knowledge for radiologists and imaging specialists.
Head and neck anatomy
Abdominal and pelvic anatomy
Axillary lymph nodes (LN) are in the axilla and receive lymph from vessels that drain the arm, the walls of the thorax, the breast and the upper walls of the abdomen.
There are five axillary lymph node groups, namely the lateral (humeral), anterior (pectoral), posterior (subscapu...
The breast is an apocrine gland seen in both males and females. However, in females it has a specific function which is the production of milk.
The breast has an inhomogeneous structure which is predominantly composed of adipose tissue and glandular tissue. In additi...
Breast hypoplasia is a condition which is characterised by underdevelopment of the breast. Breast hypoplasia can be congenital or acquired.
congenital adrenal hyperplasia
Chassaignac bursa (also known as retromammary bursa or submammary serous bursa) is the space behind the breast.
It contains loose connective tissue and aids in mobility of the breast on the thoracic wall. Posteriorly it is bound by the pectoral fascia and anteriorly by the deep layer of the su...
Cooper ligaments are the fibrous connections between the inner side of the breast skin and the pectoral muscles. Working in conjunction with the fatty tissues and the more fibrous lobular tissues, they are largely responsible for maintaining the shape and configuration of the breast. They play a...
The crests of Duret attach the most numerous superficial breast lobes by their summit to the superficial layer of fascia. The deepest crests connect the anterior lobes to the deep layer through the Cooper's ligament.
Breast lobe groups about one hundred lobules separated by interlobular connect...
The foramen of Langer is a defect in the deep pectoralis fascia. It is a defect at the level of the third intercostal space, through which the upper lateral portion of the breast extends into the axilla forming the axillary tail of Spence.
The inframammary fold is the anatomical boundary formed at the inferior border of the breast, where it joins with the chest.
In mammography, it is an important landmark to identify on the mediolateral oblique view to assess image quality.
Intramammary lymph nodes (IMLN) are lymph nodes within the breast tissue. In breast imaging, they generally fall into BIRADS II lesions 7. They can be solitary or multiple. This article discusses normal (physiological) intramammary lymph nodes.
Intramammary lymph nodes are seen in...
Lymphatic drainage of breast originates from breast lobules and flows into a subareolar plexus, called Sappey’s plexus. From this plexus, lymphatic drainage takes place through three main routes:
axillary or lateral pathway
fed by Sappey’s Plexus, as well as by ducts satellite lymphatics and b...
The mammary glands
develop in close association with a depot of adipose tissue that is commonly
referred to as the mammary fat pad.
The mammary fat pad is a matrix of adipose
and connective tissue capable of mediating hormone action and synthesizing an
array of growth regulatory molecules.
Montgomery glands are large sebaceous glands in the breast, representing a transition between a mammary gland and a sweat gland.
Located within the nipple-areolar complex, Montgomery glands open onto the skin surface via protrusions on the skin known as Montgomery tubercles. They...
Montgomery tubercles are the openings of Montgomery glands on the skin surface.
They are about 1-2 mm papules on the skin surface located on the skin of the nipple and areola.
These tubercles become prominent during stimulation and pregnancy
They are named after Wi...
During the 6th week of gestation, a pair of longitudinal thickening of the epidermis develop on the ventral surface of the embryo, extending from the axilla to the medial thigh, called "mammary ridges" (or "mammary line", “milk lines"). In large part these milk lines later atrophy, leaving only...
The pectoralis major muscle is a muscle of the pectoral region, overlying the anterior chest wall but is considered an upper limb muscle due to its function.
sternal part: sternum and superior six costal cartilages
clavicular part: medial half of the clavicle
Sappey plexus is a network of lymphatics in the areola of the nipple.
The breast is originally an ectodermal tissue, thus its lymphatic drainage is mostly parallel to the lymph flow of the overlying skin. Lymphatic flow from the skin finds its way to the diffuse subcutaneous plexus between the ...
Spence tail is the prolongation of upper outer quadrant of the breast in the axillary direction. It is also called the axillary tail, once it passes through the foramen of Langer, it pierces the axillary fascia. The duct system is seen to extend into the axilla.
If this direct continuity with t...
The sternalis muscle is an uncommon anatomic variant of the chest wall musculature and is of uncertain aetiology and function. Its importance lies in that it should not be mistaken for a pathological lesion.
Cadaveric studies have shown that the muscle is present in ~5% (range 1-...
Supernumerary nipples are a common minor congenital malformation that consists of accessory nipples.
Supernumerary nipples are located along the embryonic milk lines. Ectopic supernumerary nipples are found beyond the embryonic milk lines. In human beings, the embryonic milk line extends from a...
The supraclavicular lymph nodes are a paired group of lymph nodes located on either side in the hollow of clavicle close to the sternoclavicular joint. It is the final common pathway of the lymphatic system as it joins the central venous system. They oversee transport of lymph from the thoracic ...
The suspensory ligament of the axilla is the inferior extension of the clavipectoral fascia on each side of the thorax.
The suspensory ligament of the axilla originates from the inferior border of pectoralis minor, where the 'leaflets' of the clavipectoral fascia have fused again...
Each breast lobe is drained by a collecting duct terminating in the nipple. The collecting duct has several branches, which ends in a terminal ductal-lobular unit (TDLU), the basic functional and histopathological unit of the breast. The TDLU is composed of a small segment of the terminal duct a...