Fallopian tubes

Fallopian tubes

Also called the uterine tubes they open into the uterus at one end and are closely related to the ovaries at the other end. They can be anatomically divided into an intramural segment that passes through the uterine wall, a narrow isthmus (high risk of rupture in an ectopic pregnancy), the widest and longest segment called ampulla (site of fertilization) and a fimbriated infundibulum that is in close relation to the ovaries. The mucosal epithelium has ciliated cells that beat towards the uterus and nonciliated secretory cells. Smooth muscle is arranged in an inner circular and outer longitudinal layer. Peristaltic movements can be seen that help to move the embryo towards the uterus. Ampulla is the most common location for an ectopic pregnancy.

Ovaries

They are located on either side of the broad ligament, associated with the mesovarium. Ovaries are female gonads. The surface is covered by simple cuboidal epithelium called surface or germinal epithelium. Beneath the surface epithelium is a dense connective tissue covering called the tunica albuginea. Beneath the tunica are the cortex and an inner medulla. The cortex shows a stroma with various follicles in different stages of development. The medulla contains blood vessels, nerve fibres and lymphatics.

The ovaries are connected to the uterus by the ovarian ligament. The suspensory ligament of the ovary or the infundibulopelvic ligament attaches the ovary to the pelvic sidewall. The ovaries are supplied by the ovarian artery which is a branch of the abdominal aorta. It runs in the ovarian ligament, which connects the ovary to the uterus. The right ovarian vein drains directly into the IVC while the left ovarian vein drains into the left renal vein. The left ovarian vein is prone to compression as it is longer. Compression leads to pelvic congestion and chronic pelvic pain. The left iliofemoral vessels are the most common site of thromboembolism in pregnant patients.

Breast

They are accessory organs of the female reproductive system. It lies on the pectoralis major and serratus anterior muscles, covered by skin. It is attached to the underlying muscle and overlying dermis by suspensory ligaments of Cooper. Superolaterally, breast tissue extends into the axilla as the axillary tail of Spence. Breast tissue is a mix of adipose tissue and glandular tissue. Adipose tissue is under the influence of estrogen while glandular tissue is under the influence of progesterone. Size of the breast varies depending on the content of adipose tissue while milk production is dependent on glandular tissue.

1. Nipple and Areola: The pigmented nipple and areola are located anteriorly at the level of the fourth rib, and are lined by lightly keratinized, stratified squamous epithelium. The areola is round and has raised, sebaceous glands which enlarge during pregnancy to form the tubercles of Montgomery. The nipple lacks sebaceous glands. The lactiferous ducts open onto the surface of the nipple in a ring-like fashion. Smooth muscle fibres are situated under the nipple-areolar complex. They are arranged in radial/longitudinal and circular directions. Circular fibres are called the muscle of Sappey while radial fibres form the muscle of Meyerholz. Contraction of these muscles during breast feeding results in the ejection of milk.
2. Mammary Gland: It is a modified sweat gland. The glandular tissue is divided into lobes which are made of clusters of milk producing alveoli. Myoepithelial cells surround the alveoli. The lobules are drained first by intralobular ducts, then interlobular ducts which eventually drain into the lactiferous ducts. There are 15-20 lactiferous ducts in all. Each duct dilates towards the areola to form a lactiferous sinus. The sinus acts as a temporary reservoir for milk. Upper, outer quadrant of the breast is the major site for breast cancer as it is rich in glandular tissue.

3. Blood Supply: Major supply is from the internal mammary or internal thoracic artery. Others are thoracoacromial artery, lateral thoracic artery, vessels to serratus anterior/ thoracodorsal artery and terminal branches of the third to eight intercostal perforators. Venous drainage is divided into a superficial (plexus of Haller) and deep system.
4. Lymphatic drainage: Superficial lymphatics from the nipple and areola form the Sappey’s plexus that eventually drains into the axillary nodes. It also communicates with the deep lymphatics. Majority of the breast parenchyma is drained by the axillary nodes. Rest of the drainage is to the internal mammary or parasternal nodes, followed by the posterior intercostal nodes. Some lymphatics located more cranially may drain into the supraclavicular lymph nodes located in the cervical group. Lymphatics also communicate with the opposite breast, subdiaphragmatic and hepatic nodes.
5. Nerve Supply: Nipple sensation is from the lateral cutaneous branch of T4. Sensation to the rest of the breast is from T3-5 intercostal nerves. Upper and lateral part is also supplied by the supraclavicular branch of the cervical plexus.