Basic science 34 Breast Anatomy and Physiology

  1. Name the group of lymph nodes present in the head and neck. Explain the lymphatic drainage of head and neck. [TU 2073]
  2. Describe the gross anatomy of breast with its lymphatic drainage and correlate clinically. [Tu 2070/5]
    • The breast lies between the subdermal layer of adipose tissue and the superficial pectoral fascia.
    • The breast parenchyma is composed of lobes that comprise multiple lobules. Fibrous bands termed the suspensory ligaments of Cooper provide structural support and insert perpendicularly into the dermis. The retromammary space, a thin layer of loose areolar tissue that contains lymphatics and small vessels, lies between the breast and pectoralis major muscle.
    • Located deep to the pectoralis major muscle, the pectoralis minor muscle is enclosed in the clavipectoral fascia, which extends laterally to fuse with the axillary fascia.
  3. Milk line
    Extend from base of forelimb (axilla) to base of hind limb (inguinal region)
  4. Halsted’s ligament?
    Costoclavicular ligament at which point, the axillary vein passes into the thorax and becomes subclavicular vein
  5. Blood supply of breast?
    • 1. Perforating branches of internal mammary artery (also called as internal thoracic artery)
    • 2. Lateral branches of posterior intercostal arteries
    • 3. Branches from axillary artery

    Venous drainage follow the course of arteries

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  6. Name axillary group of lymph node. Mention the area of drainage and their surgical importance. [TU 2066/6]

    Lymph nodes of axilla?
    • Posterior (scapular) – from lower posterior back
    • Anterior (pectoral) – from lateral aspect of breast
    • Lateral (axillary) – form upper extremity
    • Central – From scapula node, axillary vein
    • Apical (subclavicular) – from all other group of LNs
    • Rotters (interpectoral) – Between pectoral major and minor, directly from breast
  7. Levels of axillary LN?
    • Level I – Lateral to pectoral minor (anterior (pectoral), lateral and posterior group of lymph nodes)
    • Level II – Deep to pectoral minor (central group)
    • Level III – Medial to pectoral minor (apical, subclavicular group of lymph nodes)

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  8. Mention lymphatic drainage of female adult breast and their surgical importance. [TU 2061,64/5]
    Lymph from skin of breast except nipple and areola - axillary lymph nodes, inferior deep cervical, infraclavicular and also parasternal lymph nodes of both sides. 

    • Lymph from nipple, areola and lobules of the gland passes to subarealar lymphatic plexus (Sappey's Plexus).
    • From these plexus >75% drain to axillary lymph (mainly anterior group).
    • Remaining lymph (25%) particularly from medial breast quadrant drains to parasternal lymph nodes or to opposite breast. 

    Image Upload 3
  9. Important nerves in breast surgery?
    Long thoracic nerve (external respiratory nerve of Bell) - innervates the serratus anterior muscle. Division of the nerve may result in the winged scapula deformity. 

    Thoracodorsal nerve – innervates the latissimus dorsi muscle.

    Medial pectoral nerve - innervates the pectoralis major muscle. The pectoral neurovascular bundle is a useful landmark because it indicates the position of the axillary vein, which is just cephalad and deep (superior and posterior) to the bundle.

    Brachial cutaneous nerves - supply sensation to the undersurface of the upper part of the arm and skin of the chest wall, denervation leads to chronic and uncomfortable pain syndrome.
  10. Tissues of breast
    • Glandular epithelium – branching system of duct which end in terminal lobules or acini and lined by myoepithelial cells. Myoepithelial cells are surrounded by basement membrane
    • Fibrous stroma and supporting structures – Coopers ligament
    • Adipose tissue – increases after menopause
  11. Hormonal effects on breast?
    • Estrogen – Ductal development
    • Progesterone – Epithelial development
    • Prolactin – Lactogenesis
Card Set
Basic science 34 Breast Anatomy and Physiology