Normal anatomy of the breast Flashcards
How do the breasts develop?
- Mammary crests or ridges appear during 4th week
- These crests extend from axillary region to inguinal region
- The crests usually disappear except in the pectoral region
- Primary mammary buds – Secondary buds – lactiferous ducts and their branches
Describe the breasts?
- Secondary sexual feature of females
- Source of nutrition for the neonates
- Present in a rudimentary form in males
- Site of malignant change in as many as 1 in 10 women
What are the general features of the breast?
•Modified and highly specialized sweat glands
No special capsule or sheath
- Both Males & females have breasts
- Well developed in females
- Breast size and shape result from genetic,racial, and dietary factors
What is the extent of the breast?
Vertical: 2nd or 3rd rib – 6th rib
What is the transverse location of the breast?
Sternal edge to midaxillary line
Where does the breast lie?
On the deep pectoral fascia
Where is the axillary tail?
A small part of breasts may extend towards axillary fossa
What does the retromarry space do?
Help some degree of movement
Where does the parts of the breast rest?
- 2/3rd of the breast rests on the pectoral fascia covering pectoralis major
- 1/3rd of the breast rests on the fascia covering serratus anterior
Where does the breast firmly attach?
To the dermis by suspensory ligament of cooper – help support the lobules of the gland
What is the nipple?
Prominence of the breast
What is the areola?
Pigmented area around the nipple
How many lobules of the breast?
•Each breast contains 15-20 lobules of glandular tissue (parenchyma)
What is each lobule of breast drained by?
Lactiferous duct – opens independently on the nipple
What is a lactiferous sinus?
Dilated portion of breast
What is important about a nipple?
- No fat or hair
- Contains collagenous dense connective tissue, elastic fibres and bands of smooth muscle
- The tips of the nipples are fissured with lactiferous ducts opening into them
What is the position of the nipple?
variable or 4th intercostal space
What is important about the areola?
- 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
What are the breast quadrants?
•For anatomical location and description of pathology (cysts and tumours) the breast is divided into 4 quadrants.