Handa 9781496386441 Full Sample Chap 1

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SECTION I  Preparing for Surgery

Superior rectal a.

Internal iliac a.

Internal pudendal a.

I

Rectosigmoid a.

Middle rectal a.

Coccygeus m.

Levator ani m.

Inferior rectal a.

External anal sphincter m.

FIGURE 1.26  The rectosigmoid colon and anal canal showing collateral arterial circulation from superior rectal (terminal branch of inferior mesenteric), middle rectal (from internal iliac), and infe- rior anal (rectal), which are branches of the internal pudendal arteries (from internal iliac).

have a supportive function as well as a role in carry- ing vessels and nerves to the organ. An understanding of their disposition is important to both vaginal and abdominal surgeries. The tissue that surrounds and connects the organs to the pelvic wall has been given the special designation of endopelvic fascia . It is not a layer similar to the layer encountered during abdominal incisions (rectus abdomi- nis “fascia”). It is composed of blood vessels and nerves, interspersed with a supportive meshwork of irregular connective tissue containing collagen and elastin. These structures connect the muscularis of the visceral organs to pelvic wall muscles. In some areas, there is consider- able smooth muscle within this tissue, as is true in the area of the uterosacral ligaments. Although surgical texts often speak of this fascia as a specific structure separate from the viscera, this is not strictly true. These layers can be separated from the viscera, just as the superficial lay- ers of the bowel wall can be artificially separated from the deeper layers, but they are not themselves separate structures.

PELVIC CONNECTIVE TISSUE The “endopelvic fascia” is a term sometimes used to refer to both parietal fascia and extraperitoneal and visceral fascia in the abdomen and pelvis. However, the term “endopelvic fascia” remains controversial. The visceral pelvic fasciae (adventitial layers) of the pelvic viscera are continuous with condensations of irregular connective tissue on the lateral walls of the organs, which transmit vessels and nerves and blend with the thickenings of the connective tissues that lie over the pelvic wall muscles. These attachments, as well as the attachments of one organ to another, separate the different surgical cleavage planes from one another ( FIG. 1.27 ). These condensations of the endopelvic fasciae surrounding the pelvic organs have assumed supportive roles, connecting the viscera to the pelvic walls, in addition to their role in transmit- ting the organs’ neurovascular supply from the pelvic wall. They are somewhat like a mesentery that con- nects the bowel, for example, to the body wall. They

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