tailieunhanh - Ebook The ABSITE review: Part 2

(BQ) Part 2 book “The ABSITE review” has contents: Gastrointestinal hormones, biliary system, anal and rectal, small bowel, hernias, abdomen, and surgical technology, pediatric surgery, statistics and patient safety, orthopedics, neurosurgery, gynecology, and other contents. | CHAPTER 24. BREAST ANATOMY AND PHYSIOLOGY Breast development • Breast formed from ectoderm milk streak • Estrogen – duct development (double layer of columnar cells) • Progesterone – lobular development • Prolactin – synergizes estrogen and progesterone Cyclic changes • Estrogen – ↑ breast swelling, growth of glandular tissue • Progesterone – ↑ maturation of glandular tissue; withdrawal causes menses • FSH, LH surge – cause ovum release • After menopause, lack of estrogen and progesterone results in atrophy of breast tissue Nerves • Long thoracic nerve – innervates serratus anterior; injury results in winged scapula • Lateral thoracic artery supplies serratus anterior • Thoracodorsal nerve – innervates latissimus dorsi; injury results in weak arm pull-ups and adduction • Thoracodorsal artery supplies latissimus dorsi • Medial pectoral nerve – innervates pectoralis major and pectoralis minor • Lateral pectoral nerve – pectoralis major only • Intercostobrachial nerve – lateral cutaneous branch of the 2nd intercostal nerve; provides sensation to medial arm and axilla; encountered just below axillary vein when performing axillary dissection • Can transect without serious consequences Branches of internal thoracic artery, intercostal arteries, thoracoacromial artery, and lateral thoracic artery supply breast Batson’s plexus – valveless vein plexus that allows direct hematogenous metastasis of breast CA to spine Lymphatic drainage • 97% is to the axillary nodes • 2% is to the internal mammary nodes • Any quadrant can drain to the internal mammary nodes • Supraclavicular nodes – considered N3 disease • Primary axillary adenopathy – #1 is lymphoma Cooper’s ligaments – suspensory ligaments; divide breast into segments • Breast CA involving these strands can dimple the skin BENIGN BREAST DISEASE Abscesses – usually associated with breastfeeding. Staphylococcus aureus most common, strep • Tx: percutaneous or incision and drainage; discontinue breastfeeding; breast pump,