Breast Anatomy 01/02 Flashcards
The ‘breast’ involves 3 main components, what are these?
Mammary glands (modified sweat glands) Superficial fascia (connective tissue) Overlying skin on the area
Where anatomically is the location of a breast?
On the pectoral region on each side of the thoracic wall
What is the mammary gland composed of? (2)
Glandular tissue (secretory glands) Adipose tissue (fat tissue)
What is the function of the 3 main hormones (Oestrogen, Progesterone and Prolactin)?
They cause glandular tissue in the breast and the uterus to change during the menstrual cycle
At puberty what does an increase in circulating oestrogen result in?
The growth of ducts, lobules, connective tissue and fat to form the adult breast
What is the pre-dominant component of breast in non-lactating women?
Fat (+ proportion gets larger with age)
What are the 3 major hormones that affect the breast?
Oestrogen
Progesterone
Prolactin
During pregnancy, what do high levels of oestrogen and progesterone stimulate?
The production of glandular breast tissue in preparation for lactation
What is the location of the breast cranio-cordially?
2nd to 6th rib
What does cranio-cordially mean?
From head to toe
What is the location of the breast posteriorly?
Posteriorly to fasciae of pectoralis major
What is the location of the breast laterally?
Laterally mammary fold usually lies at the anterior axillary line (but may extent to latissimus dorsi muscle) and breast tissue can extend to the mid-axillary line
What is the location of the breast medially?
Medially lateral border of sternum to midline
What is ptosis?
Drooping of the breast
What can ptosis (drooping) mean in regard to radiotherapy?
A significant proportion of breast tissue may lie inferior to the mammary fold which can cause problems as if the breast droops too low it can result in issues with lower internal structures e.g. lungs receiving unnecessary radiation
Where does the upper lateral breast region project?
Around the lateral margin of the pectoralis major muscle into the axilla
What are the 2 other names for the axillary process?
Axillary tail
Tail of Spence
What does the surface anatomy of the breast include?
Normal skin, except at the areola which is pigmented and contains a large number of sebaceous glands. The skin is associated with varied thickness of subcutaneous fat
Where does the axillary tail extend?
Into the anterior axillary fold
Where is the nipple found, what is it composed of and what is its function?
Found near the centre of the areola, contains dense fibrous connective tissue and its function is the expression of milk produced by the lobules
What shape/colour is the areola and what glands does it contain?
Small dark pigmented oval shape that contains sebaceous glands, sweat glands and accessory areola glands (glands of Montgomery)
How many lobes is the breast made up of?
12-20 lobes formed of smaller lobules
What are breast lobules formed from?
A cluster of alveoli
What do ducts and secretory lobules combine to form?
15-20 lactiferous ducts (stratified squamous epithelium) which open independently to deliver milk to the nipple
