Anatomy, blood supply and lymph drainage of breast

Anatomy, blood supply and lymph drainage of breast

roughly circular base extending:

transversely from lat. border of sternum to midaxillary line.

vertically from 2^nd - 6^th ribs

the breasts lie 2/3 on the deep pectoral fascia & 1/3 on fascia covering serratus ant.

retromammary space: potential space containing loose c.t. & fat, located between the pectoral fascia & breast

the mammary gll.:

suspenssory lig.: attaching mammary gll. to dermis.

divided into 15-20 lobules. each drained by lactiferous duct, that usually open independently on the nipple.

lactiferous sinus: formed by the dilatation of the ducts deep the areola. store milk during lactation.

tubuloalveolar gll. alveoli arranged in grape-like clusters.

modified sweat gll.

- The axillary tail (of Spence): a small part of the mammary gl. may extend along the inferolat. edge of pectoralis major towards thw axilla. may enlarge during menstrual cycle.

Areola: circula pigmented skin surrounding the nipple. contain sabeceous gll. that elarge during pregnancy & secrete oily substance that protect areola & nipple.

nipple: a conical prominence at the center of the areola. usually located at the level of 4^th intercostals space. it is composed of circular smooth m. ff. that compress the lactiferous ducts during lactation & erect the nipples in response to stimulus.

Blood supply:

Medial mammary branches of perforating branches and ant. Intercostals branches of the internal thoracic a.( coming from subclavian artery)

Lat. Thoracic a. and thoracoacromial aa., branches of axillary a.

Post. Intercostals aa., branches of thoracic aorta in 2^nd -4^th intercostal spaces

Venous drainage:

Mainly to axillary v.

Some to internal thoracic v.

Lymph drainage:

Axillary lymph nodes( apical, humeral, central, pectoral, subscapular lymph nodes) > clavicular (infra/supra clavicular) lymph nodes > subclavian lymphatic trunk(also drain upper limbs)

Parasternal lymph nodes > bronchomediastinal lymphatic trunk( also drain thoracic viscera)

Both drained to >>> right/ thoracic duct >>> venous angle

Innervation:

Nerves of breast derived from intercostals n. (2-6)

Clinical:

• mammography: radiographic examination of the breasts. used in order to detect cancer & as a guide in removal of brain tumors, cysts & abscesses.
• lactogram: insertion of opaque material for examination with x-rays.