DMS Study Guide 2026 – Diagnostic Medical Sonography Comprehensive Review
and Exam Preparation
Between the skin and chest wall, the breast is subdivided by fascial planes into three layers -
correct answer ✔✔ The subcutaneous fat layer
The mammary (parenchymal) layer
The retromammary fat layer
What is the nipple? - correct answer ✔✔ a round fibromuscular papilla projecting from the
center of the breast that is encircled by the pigmented areola
What does small bumps on the areola mark the sites as? - correct answer ✔✔ sebaceous glands
(Montgomery glands), which secrete an oily substance to lessen drying and cracking of the
nipple during breastfeeding.
What is within the mammary layer? - correct answer ✔✔ 15-20 overlapping lobes arranged in a
fashion around nipple
What does each lobe contain? - correct answer ✔✔ 20 to 40 terminal ductolobular units
(TDLUs) which are the functional units of the breast
What is the primary arterial blood supply breast? - correct answer ✔✔ branches from the
interna thoracic mammary artery, the lateral thoracic artery, and to a lesser extent the
thoracoacromial artery.
Where does arterial anastomoses occur the breast? - correct answer ✔✔ beneath the areola
, Where does the majority of breast lymph drains into? - correct answer ✔✔ the axillary lymph
nodes with lesser drainage to the internal mammary nodes, interpectoral (Rotter) nodes and
the supraclavicular nodes
What is the anatomic layers of the breast? - correct answer ✔✔ skin, subcutaneous
(premammary) layer, mammary layer
retromammary space, muscle layers, chest wall
The muscle layer are: - correct answer ✔✔ pectoralis major muscle
pectoralis minor muscle
What is the ultrasound normal appearance of the breast layers are: - correct answer ✔✔ Skin:
hyperechoic fat - medium gray, Cooper's ligaments - echogenic linear structures
Mammary layer: isoechoic or slightly hypoechoic to fat, lactiferous ducts - hypoechoic
Muscles: hypoechoic with echogenic striations
Ribs: hyperechoic with shadowing
What are the most common developmental anomalies of the breast? - correct answer ✔✔
Amastia: absence of breast
Polymastia: more than 2 breasts
Athelia: absent nipple
Polythelia: acessory nipple
Nipple inversion
What are the normal ultrasound findings of the normal intramammary lymph node? - correct
answer ✔✔ The size of a normal intramammary node is typically less than 1 cm, but axillary
nodes can be much larger. nodes are oval or reniform in shape, well circumscribed, oriented
parallel to the skin, and display a symmetric hypoechoic outer cortex and a hyperechoic fatty
hilum
and Exam Preparation
Between the skin and chest wall, the breast is subdivided by fascial planes into three layers -
correct answer ✔✔ The subcutaneous fat layer
The mammary (parenchymal) layer
The retromammary fat layer
What is the nipple? - correct answer ✔✔ a round fibromuscular papilla projecting from the
center of the breast that is encircled by the pigmented areola
What does small bumps on the areola mark the sites as? - correct answer ✔✔ sebaceous glands
(Montgomery glands), which secrete an oily substance to lessen drying and cracking of the
nipple during breastfeeding.
What is within the mammary layer? - correct answer ✔✔ 15-20 overlapping lobes arranged in a
fashion around nipple
What does each lobe contain? - correct answer ✔✔ 20 to 40 terminal ductolobular units
(TDLUs) which are the functional units of the breast
What is the primary arterial blood supply breast? - correct answer ✔✔ branches from the
interna thoracic mammary artery, the lateral thoracic artery, and to a lesser extent the
thoracoacromial artery.
Where does arterial anastomoses occur the breast? - correct answer ✔✔ beneath the areola
, Where does the majority of breast lymph drains into? - correct answer ✔✔ the axillary lymph
nodes with lesser drainage to the internal mammary nodes, interpectoral (Rotter) nodes and
the supraclavicular nodes
What is the anatomic layers of the breast? - correct answer ✔✔ skin, subcutaneous
(premammary) layer, mammary layer
retromammary space, muscle layers, chest wall
The muscle layer are: - correct answer ✔✔ pectoralis major muscle
pectoralis minor muscle
What is the ultrasound normal appearance of the breast layers are: - correct answer ✔✔ Skin:
hyperechoic fat - medium gray, Cooper's ligaments - echogenic linear structures
Mammary layer: isoechoic or slightly hypoechoic to fat, lactiferous ducts - hypoechoic
Muscles: hypoechoic with echogenic striations
Ribs: hyperechoic with shadowing
What are the most common developmental anomalies of the breast? - correct answer ✔✔
Amastia: absence of breast
Polymastia: more than 2 breasts
Athelia: absent nipple
Polythelia: acessory nipple
Nipple inversion
What are the normal ultrasound findings of the normal intramammary lymph node? - correct
answer ✔✔ The size of a normal intramammary node is typically less than 1 cm, but axillary
nodes can be much larger. nodes are oval or reniform in shape, well circumscribed, oriented
parallel to the skin, and display a symmetric hypoechoic outer cortex and a hyperechoic fatty
hilum
