BREAST
- They are modified sweat glans in the superficial fascia of the pectoral region in both sexes.
- In females it reaches its full development at puberty, and is rudimentary in males.
- Hemispherical in shape. ↪ due to high fat content.
- It extends ventrically from 2ed to 6th rib (midclavicular line), and horizontally from lateral border of the sternum to the mid-axillary line. ↪ In females who have never given birth.
- It may have an extension (axillary tail) which penetrate the deep pectoral fascia to be present in the axilla.
Blood supply :
- Venous drainage: through veins corresponding to the arteries.
Innervation :
2ed - 6th intercostal nerves.
has no fibrous capsule. → If there is the breast couldn't change its size
* After the first pregnancy the color of the nipple and areola becomes dark brown.
Structure of the breast
- 1. The nipple :
- light brown conical projection below the center of the breast.
- It lies at the level of 4th intercostal space.
- It is penetrated by 15-20 lactiferous ducts.
- 2. The areola :
- area of the skin surrounding the nipple
- It contains sebaceous glands which enlarges during pregnancy to form tubercles of Montogermy.
- 3. The glandular tissue:
- 3.1 lobes : - 15-20 lobes - Formed of alveoli and drained by one lactiferous duct.
- 3.2 Lactiferous ducts : - Each duct form a dilation called. lactiferous sinus before it opens into the nipple.
- 4. Fibrous Supporting framework:
- 4.1 Fibrous stroma (Suspensory ligaments) : - Passing between lobes, and binding the skin of the breast to the underlying pectoral fascia.
- 4.2 Fatty stroma : - forms the main bulk of the breast. It present all over the breast except nipple and sub-areolar area.