Breast - Repro Y3 Flashcards
function
source of nutrition for neonates - production of human milk
location and relations
vertical extent: 2nd/3rd rib - 6th rib
transverse: sternal edge to midaxillary line
lies on deep pectoral fascia
which muscles do they cover
2/3 rests on pectoral fascia covering pectoralis major
1/3 rests on fascia covering serratus anterior
how are attached to dermis
suspensory ligament of cooper - support the lobules of the gland
structure - nipple
prominence of breast
structure - areola
pigmented area around the nipple
structure - glandular tissue
contains around 15-20 lobules of glandular tissue (parenchyma)
how are lobules drained
lactiferous duct - opens independently on the nipple
dilated portion of duct
lactiferous sinus
nipple features
no fat or hair
contains collagenous dense connective tissue, elastic fibres and bands of smooth muscle
tips of nipples are fissured with lactiferous ducts opening into them
position: variable or 4th ICS
areola features
skin covering the nipple and areola contains numerous sweat & sebaceous glands
enlarge during pregnancy
oily material secreted by the sebaceous gland provides a protective lubricant for nipple and areola
4 quadrants of breast
superolateral quadrant
superomedial quadrant
inferolateral quadrant
inferomedial quadrant
what is extension of superolateral quadrant called
axillary tail
gynecomastia
postnatal development of rudimentary lactiferous ducts in males
during midpuberty about 2/3 of boys develop varying degrees of hyperplasia of the breasts
define polymastia
an extra breast
define polythelia
extra nipple
define athelia or amastia
absence of nipple or breast
function of ligaments (of Cooper)
attach and secure breast to dermis and underlying pectoral fascia
separate the secretory lobules of the breast
arterial supply to medial aspect of breast
internal thoracic artery (aka internal mammary artery) - branch of subclavian artery
retromammary space
between breast and pectoral fascia - often used in reconstructive plastic surgery
arterial blood supply to lateral aspect of breast
lateral thoracic and thoracoacromial branches - originate from axillary artery
lateral mammary branches - post intercostal arteries (derived from aorta)
— supply lateral aspect in 2nd, 3rd and 4th ICS
mammary branch - originates from anterior intercostal artery
venous drainage
veins correspond with the arteries, draining into the axillary and internal thoracic veins
lymphatic drainage
axillary nodes (75%)
parasternal nodes (20%)
posterior intercostal nodes (5%)
skin also receives lymphatic drainage
skin - drains to axillary, inferior deep cervical and infraclavicular nodes
nipple and areola - drains to subareolar lymphatic plexus
nerves of breast
anterior and lateral cutaneous branches of 4th-6th intercostal nerves
- sensory fibres to skin of breast
- sympathetic fibres to blood vessels and smooth muscle around nipple
