Breast
US appearance of subcutaneous layer
skin appears as 2 thin echogenic lines fat is hypoechoic relative to skin and connective tissue cooper ligaments thin, hyperechoic, curvilinear bands
Montgomery glands
small bumps on the areola that mark the sites of sebaceous glands secrete a lubricating and protective substance
3 layers of the breast
subcutaneous fat layer mammary (parenchymal) layer retromammary fat layer
Subcutaneous fat layer
superficial layer of the breast contains skin and fat connective tissue
Cooper's ligaments
suspensory ligaments that support breast from the deep fascia to the skin
Areola contains ________ tubercules
Montgomery's AKA glands of montgomery
TDLU
Terminal ductolobular units 20-40 small lobules
Tail of Spence
a portion of mammary tissue which extends into the region of the axilla
Lymph nodes US appearance
flat, oval, hypoechoic solid mass peripheral, hypoechoic rim (halo) containing an echogenic fatty hilus
Breast primary function
produce milk to nourish offspring
Diagnostic quality
very operator and equipment dependent
Parenchyma contains how many lobes?
15-20
Ampulla
AKA lactiferous sinus region where lactiferous duct expands to store milk AKA Montgomery's gland
Mammography alone CAN or CANNOT directly determine whether a mass is cystic or solid???
Cannot
Microcalcifications
first imaging sign of a developing
Parenchymal layer
aka mammary layer contains glandular tissue, ducts, and connective tissue
Breast position
anterior chest wall adjacent and medial to the auxilla
Breast location
anterior to the pectoralis major medial to axilla
Arterial anastomoses are found beneaththe ______
areola
axilla
armpit contains the lymph nodes that drain the breast tissue
Veins follow the same course as _______
arteries
Primary arterial blood supply
branches of the internal mammary and lateral thoracic arteries and to a lesser extent thoracoacromial and intercostal arteries
Lactiferous ducts
ducts in the parenchyma of the breast that secrete milk
Ducts US appearance
echopoor tubular structures
Adenopathy
enlarged lymph nodes
Stromal elements
fat and all the connective tissue blood vessels, lymphatics, and nerves
Parenchyma
functional fibroglandular tissue contains the functional glandular elements of the breast and supporting connective tissues
US appearance of glandular tissue
homogeneous in texture medium level to low level echogenicity
US appearance of nipple
homogeneous texture medium-level echoes can cause acoustic shadowing
Glandular tissue in juvenile
hyperechoic little fat
Lobules US appearance
hypoechoic as fat
Glandular tissue during pregnancy/lactating
increased glandular tissue granular pattern
Lactation
milk secretion due to hormone prolactin from anterior pituitary under influence of progesterone and estrogen
Mammary glands
modified sweat glands exocrine organ whose main function is the secretion of milk
Histologic importance of TDLUs
most benign and malignant breast diseases arise from this structure
Glandular tissue in postmenopausal
mostly involuted high amount of fat
US appearance of retromammary layer
narrow hypoechoic layer defines posterior boundary to gland
Male breasts consist primarily of _____ and ______
nipple, areola
Milk ejection
occurs in presence of oxytocin from posteroir pituitary stimulation of infant sucking
Ribs US appearance
oval, hypoechoic structures attenuate sound with posterior acoustic shadowing
Breasts
paired, dome shaped structures modified sweat gland AKA mammary glands
Glandular tissue in premenopausal
partly involuted more amount of hyperechoic fat
Retromammary fat layer
posterior portion of the breast contains fat, muscle and deep connective tissue
Pectoralis major muscle
posteriorly borders the retromammary layer of the breast
Parenchymal/Glandular elements
primarily function to produce and transport milk lobes, lobules, ducts, acini
Lymphatics
transfer infection or malignancy from breast to more distant areas
UOQ
upper outer quadrant where majority of glandular tissue lies