Subcutaneous layer: This consists of fat globules in a meshwork of fibrous septa. Camper fascia is the more superficial aspect of the subcutaneous layer.
Scarpa fascia is the deeper portion and has a more organized consistency than Camper fascia secondary to more fibrous tissue.

Musculoaponeurotic layer: Located immediately below the subcutaneum, the musculoaponeurotic layer consists of layers of fibrous tissue and muscles that hold the abdominal viscera in place.

Peritoneum: A single layer of serosa lines the posterior aspect of the anterior abdominal wall. Five vertical folds converge toward the umbilicus.

Subcutaneous vascular supply (Fig. 26-3)

Musculofascial blood supply parallels the subcutaneous supply (see Fig. 26-3).

Vertical: A midline incision provides optimal exposure to the abdomen. The incision is made from the symphysis to below the umbilicus, depending on how much space is needed. A small incision or “mini-lap” may offer excellent visualization and improved cosmesis. The incision can always be extended more cephalad and then circumferentially around the umbilicus to the left to avoid the ligamentum teres. The anterior rectus sheath is incised longitudinally. The peritoneum is entered taking care to avoid the superior aspect of the bladder.

Pfannenstiel incision: This is one of the most common incisions in obstetrics and gynecology. A transverse incision is made approximately two fingerbreadths (3 to 4 cm) above the pubic symphysis. Transverse incisions are generally less painful and more cosmetic than longitudinal incisions as they run along Langer lines. The incision is continued through the rectus sheath, and then the rectus muscles are dissected cephalad and caudad off the posterior aspect of the rectus sheath. Then, the rectus muscles are separated in the midline to gain entry to the peritoneum through a midline longitudinal incision. The degree of separation of the rectus
fascia from the underlying rectus muscles determines the amount of exposure provided by the Pfannenstiel incision. If more space is needed, the rectus fascia can be separated from the rectus muscle up to the umbilicus. Lateral extension of the skin incision runs a greater risk of injury to the ilioinguinal and iliohypogastric nerves either by direct incision or more often by entrapment during fascial closure.

Cherney incision: A modification of the Pfannenstiel incision, the Cherney incision provides better exposure to the pelvis than the Pfannenstiel. After the rectus muscle is dissected off the fascia, as in a Pfannenstiel, the tendinous insertion of the rectus muscle is cut approximately 0.5 cm above the insertion site at the posterior aspect of the pubic bones. The rectus bellies are then moved cephalad, providing excellent exposure to the pelvis. Note the importance of leaving enough tendons on the pubic bone so that the caudal aspect of the rectus muscles can be reapproximated to the tendon with a delayed absorbable suture in a horizontal mattress fashion during closure.

Maylard incision: The Maylard incision provides the best pelvic exposure of all the incision types. This incision is transverse, like the Pfannenstiel, with two main differences. The Maylard incision is made slightly more cephalad (at the level of the anterior superior iliac spine), and the rectus muscles are not dissected off the fascia. Rather, they are left attached to the rectus sheath and the muscles are transected. The inferior epigastric vessels are identified and ligated before the rectus muscles are transected completely. This helps to prevent blood loss from inadvertent inferior epigastric injury and also serves to preserve blood supply. This type of incision has the potential for greater blood loss but also for better pelvic exposure.

Primary laparoscopic trocars are placed for initial access. In gynecology, these are most often placed at the umbilicus or in the left upper quadrant. Accessory trocars may be placed suprapubically or laterally (see Fig. 26-3).

The vagina is shaped like a flattened tube, starting at the distal hymenal ring and ending at the fornices surrounding the proximal cervix. Its average length is 8 cm; this varies greatly with age, parity, and surgical history.

The vaginal epithelium is nonkeratinized, stratified squamous epithelium lacking mucous glands and hair follicles.

Deep to the epithelium is the vaginal muscularis or endopelvic fascia. The term fascia is misleading because this is actually fibromuscular tissue that includes fibroblasts, smooth muscle cells, and elastin, in addition to type I and III collagen, all loosely arrayed to create an elastic supportive layer. At the vaginal apex, this fibromuscular layer coalesces to create the cardinal and uterosacral ligaments. The fanshaped cardinal ligament creates a sheath that envelops the uterine artery and vein, fusing medially with the paracervical ring. The uterosacral portion inserts into the posterior and lateral aspect of the paracervical ring and then curves laterally along the pelvic sidewall to attach to the presacral fascia that overlies the second, third, and fourth sacral vertebrae. Together, the cardinal and uterosacral ligaments pull the vagina proximally toward the sacrum, suspending it over the muscular levator plate.

The endopelvic fascias of the anterior and posterior vaginal wall are known as the pubocervical fascia and rectovaginal fascia, respectively. Again, these layers are not true fasciae but composed of fibromuscular sheets. Superiorly, the pubocervical fascia attaches to the cervix and the cardinal/uterosacral support of the vaginal apex. Laterally, it coalesces with the fascia of the obturator internus muscle to create the arcus tendineus fascia pelvis (ATFP) or “white line.” Inferiorly, it attaches to the pubic symphysis. The rectovaginal fascia in the upper vagina coalesces with the lateral support of the anterior vaginal wall and fuses with the ATFP. The lower half of the rectovaginal fascia fuses with the aponeurosis of the levator ani muscles along a line referred to as the arcus tendineus fascia rectovaginalis. At its most inferior point, the rectovaginal septum fuses with the perineal body (Fig. 26-4).

The uterus is a fibromuscular organ composed of the corpus and the cervix.

Corpus: The endometrium is the innermost lining of the uterus made up of columnar epithelium and specialized stroma. The superficial layer of the endometrium contains hormonally sensitive spiral arterioles, which shed with each cycle. The myometrium contains interlacing smooth muscle fibers, and the serosal surface of the uterus is formed by peritoneal mesothelium. The fundus is the portion of the uterus cephalad to the endometrial cavity. The cornua are located where the fallopian tubes insert into the uterine cavity, lateral to the fundus.