Handa 9781496386441 Full Sample Chap 1

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CHAPTER 1  Surgical Anatomy of the Female Pelvis

with only a small amount (approximately 10%) of smooth muscle. This smooth muscle is located peripher- ally within the cervix, connecting the myometrium with the muscle of the vaginal wall. This smooth muscle and accompanying fibrous tissue are easily dissected off the underlying, denser fibrous cervix core and form the layer reflected during intrafascial hysterectomy. It is circularly arranged around the fibrous cervix and is the tissue into which the cardinal and uterosacral ligaments attach. The vaginal part is covered by nonkeratinizing squamous epithelium. Its canal is lined by a columnar mucus-secreting epithelium that is thrown into a series of V-shaped folds that appear like the leaves of a palm and are therefore called palmate folds. These form com- pound clefts in the cervical canal, not tubular racemose glands, as formerly thought. The upper border of the cervical canal is the inter- nal os, above which the narrow cervical canal widens out into the endometrial cavity. The lower border of the canal is the external cervical os. The transition from the squamous epithelium of the vaginal part to the colum- nar epithelium of the cervical canal by the process of squamous metaplasia occurs near the external os. The resultant transformation zone is located variably in relation to the external os, changing with hormonal variations that occur during a woman’s life. It is in this active area of cellular transition that the cervix is most susceptible to malignant transformation. There is little adventitia in the uterus, with the peri- toneal serosa being directly attached to most of the cor- pus. The anterior portion of the uterine cervix is covered by the bladder; therefore, it has no serosa. Similarly, as discussed in the following section, the broad ligament envelops the lateral aspects of the cervix and body of the uterus; therefore, it has no serosal covering there. The

posterior cervix does have a serosal covering as the cul- de-sac peritoneum reflects onto the posterior vaginal wall several centimeters from the cervicovaginal junction. Adnexal Structures and Broad Ligament The uterine (fallopian) tubes are paired tubular struc- tures 7 to 12 cm in length ( FIG. 1.23 ). Each has four recognizable portions. At the uterus, the tube passes through the uterine wall (intramural part), also called the interstitial portion. On emerging from the body, a narrow isthmic portion begins with a narrow lumen and thick muscular wall. Proceeding toward the abdominal end, next is the ampulla, which has an expanding lumen and more convoluted mucosa. The fimbriated end of the tube has many frondlike pro- jections to provide a wide surface for ovum pickup. The distal end of the fallopian tube is attached to the ovary by the ovarian fimbria or fimbria ovarica, which is a smooth muscle band responsible for bringing the fimbria and ovary close to one another at the time of ovulation. The outer layer of the tube’s muscularis is composed of longitudinal fibers; the inner layer has a circular orientation. The lateral pole of the ovary is attached to the pel- vic wall by the suspensory ligament of ovary (infun- dibulopelvic ligament), composed of the ovarian artery, vein, lymphatics, and nerve plexus. Medially, the ovary is connected to the uterus through the ligament of the ovary (utero-ovarian ligament). During reproductive life, the ovary measures about 2.5 to 5 cm long, 1.5 to 3 cm thick, and 0.7 to 1.5 cm wide, varying with its state of activity or suppression, as with oral contracep- tive medications. Its surface is mostly free but has an attachment to the broad ligament through the mesovar- ium, as discussed below.

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Tubal branch of uterine artery

Tubal branch of ovarian artery

Ovary

Uterus (posterior wall)

Ovarian artery

Sampson artery to round ligament

FIGURE 1.23  Posterior view of uterine adnexa and collateral circulation of uterine and ovarian arteries. The uterine artery crosses over the ureter at the base of the broad ligament and gives off cervi- cal and vaginal branches before ascend- ing adjacent to the wall of the uterus and anastomosing with the medial end of the ovarian artery. Note the small branch of the uterine or ovarian artery that supplies the round ligament (Sampson artery).

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Uterine artery

Vaginal artery

Uterosacral ligament

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