2 Laparoscopic Anatomy of the Pelvis Intra-Abdominal Anatomy of the Male Pelvic Region Prostatic Fascia Bladder Denonvilliers’ Fascia Medial Umbilical Ligaments Rectourethralis Muscle Lateral Umbilical Ligaments Prostatic Neurovascular Plexus Spermatic Cords Accessory Pudendal Arteries Iliac Vessels Sphincteric Complex Ureters Urethra Seminal Vesicular Complex Rhabdomyosphincter Rectum and Sigmoid Colon Intra-Abdominal Anatomy of the Female Pelvic Region Retropubic Space Overview and Compartments Pubis Bladder and Urethra Obturator Muscles Vagina, Cervix, and Uterus Bladder Ovaries and Fallopian Tubes Endopelvic Fascia Ureters Santorini’s Plexus Vascular and Lymphatic Supplies Prostatic Fascia and Prostatic Pedicles Nerve Supply Intra-Abdominal Anatomy of the spermatic vessels can be visualized entering the Male Pelvic Region deep inguinal ring (Figure 2.1). Bladder A view of the anterior pelvic wall within the abdomen shows three cord-like peritoneal folds that appear to The dome of the bladder is the mobile portion of attach the bladder to the umbilicus: the median the bladder, and it stands out centrally. The anatomic umbilical ligament (or median umbilical fold) and relationships of the bladder change according two medial umbilical ligaments (or medial umbilical to its level of fullness. Because a Foley catheter folds). The median umbilical ligament extends from must be inserted into the bladder before the pneu- the dome of the bladder to the umbilicus and cor- moperitoneum is created, the bladder is initially responds to the remnants of the fetal urachus. The empty and its limits are not clearly demarcated. medial umbilical ligaments arise from the pelvis as As the bladder fills, its limits become more clearly a continuation of the internal iliac artery and extend delineated. Laterally, it expands toward the medial to the umbilicus. These are the obliterated segments umbilical ligaments; anterior and superiorly, it of the fetal hypogastric arteries. More laterally, the expands toward the median umbilical ligament lateral umbilical ligaments consist of peritoneal folds and the umbilicus, to which it is attached through covering the epigastric vessels. Further laterally, the the urachus. 17 18 2. Laparoscopic Anatomy of the Pelvis Figure 2.1. Umbilical ligaments (transperitoneal view of right hemipelvis). UL = median umbilical ligament, MUL = medial umbilical ligament, LUL = lateral umbilical ligament, B = bladder, V = vas deferens, SpV = spermatic ves- sels, EIV = external iliac vein, U = ureter The median umbilical ligament (urachus) consti- The pouch of Douglas (Figure 2.2) appears as a tutes a fibromuscular cord, broad at its attachment cul-de-sac between the bladder anteriorly and the to the bladder but narrowing as it ascends. It is a rectum posteriorly. Its depth varies among patients, vascularized structure with few vessels that need to and it is used to make a posterior approach to the be controlled during dissection of the bladder. This seminal vesicles. The exact location of the seminal fulguration can be avoided in case the urachus is vesicles cannot be readily visualized, but they are spared. Laterally, the median umbilical ligament is often found about 2 cm above the deepest part of separated from the medial umbilical ligament by the pouch of Douglas. The outline of the seminal the medial umbilical fossa, an anatomic landmark vesicles and the distal portions of the vas deferens to access the space of Retzius. are occasionally visible in thin patients. It is important to emphasize the coalescence of The visceral peritoneum and the underlying fat, the urachus and medial umbilical ligaments to the which compose the anterior aspect of the pouch anterior parietal peritoneal wall during embryo- of Douglas that covers the bladder posteriorly, logic development to understand the planes that are rich in small vessels that should be fulgurated need to be incised during avascular access to the when incised to gain access to the seminal vesi- space of Retzius. Similar to the coalescence of cles so that the surgical field is kept as bloodless the colonic gutters to the parietal peritoneal wall as possible. to form the fascias of Toldt, both the urachus and umbilical ligaments coalesce to the anterior pari- Medial Umbilical Ligaments etal peritoneal wall; this is the plane that must be identified and developed to dissect the bladder off In the fetus, the hypogastric artery is twice as large the anterior wall in a bloodless field (see laparo- as the external iliac artery, and it is the direct con- scopic radical prostatectomy, Chapter 9). tinuation of the common iliac artery. It ascends Intra-Abdominal Anatomy of the Male Pelvic Region 19 Figure 2.2. Pouch of Douglas. B = bladder, V = vas deferens, U = ureter, IIA = internal iliac artery, EIV = external iliac vein, R = rectum, Si = sigmoid colon along the side of the bladder and runs upward on The ureter travels over the iliac vessels to run the back of the anterior abdominal wall to converge medial and deep to the medial umbilical ligament. at the umbilicus with the hypogastric artery of the Therefore, as long as the surgeon is able to visualize opposite side. Having passed through the umbilical the umbilical ligament during pelvic lymph node opening, the two arteries, now termed umbilical, dissection and dissect lateral to it, the ureter will not enter the umbilical cord, where they are coiled be at risk (see Chapter 7). around the umbilical vein, and ultimately ramify in Laterally, the medial umbilical ligament is sepa- the placenta. rated from the lateral umbilical ligament (the fold At birth, when the placental circulation ceases, of peritoneum covering the inferior epigastric only the pelvic portion of the artery remains patent artery) by the medial umbilical fossa. This fossa and constitutes the hypogastric and the first part of is transversely divided into two portions by the the superior vesical artery in the adult; the remain- vas deferens to form a quadrangle anteriorly and a der of the umbilical artery is converted into a solid triangle posteriorly. While the anterior quadrangle fibrous cord, the medial umbilical ligament. This delimits an avascular access to Retzius’ space, the ligament is rarely vascularized and most often com- posterior triangle is crucial to gain access to the pletely obliterated. The prominence of the medial obturator fossa for pelvic lymph node dissection. umbilical ligaments varies depending on the amount The vas deferens forms its base anteriorly, the of adipose tissue around it. The medial umbilical external iliac vein laterally, and the medial umbili- ligaments are particularly easy to see in laparoscopy cal ligament medially; the ureter can be visualized and represent an important anatomic landmark for at the apex of the triangle (as it crosses over the dissection not only of the pelvic lymph nodes but iliac vessels) as well as deep on its medial aspect also of Retzius’ space. (Figure 2.3). 20 2. Laparoscopic Anatomy of the Pelvis Figure 2.3. Base of vasculodeferential triangle composed of vas deferens (V) anteriorly, of medial umbilical liga- ment (MUL) medially, and of medial aspect of external iliac vein (EIV) laterally; triangle contains obturator lymph nodes along with obturator nerve and vessels (not visible). SpV = spermatic vessels, EIA = external iliac artery, GFN = genitofemoral nerve, B = bladder, U = ureter, IIA = internal iliac artery Lateral Umbilical Ligaments ilioinguinal and sympathetic spermatic plexus), and the gonadal vessels. The gonadal artery runs The inferior epigastric artery is a medial branch over the iliopsoas muscle and joins the vas deferens of the distal segment of the external iliac artery. It before entering the deep inguinal ring. The gonadal ascends along the medial margin of the deep inguinal veins ascend on the psoas major, behind the peri- ring, continues between the rectus abdominis mus- toneum, lying on each side of the gonadal artery. cle and the posterior lamina of its sheath, and then They unite to form a single vein, which opens on abuts on the anterior parietal peritoneum to create the right side at an acute angle into the inferior the lateral umbilical ligament. This ligament is the vena cava, and on the left side at a right angle into least pronounced of the three aforementioned peri- the left renal vein. toneal folds, and it is not always readily visualized. The vas deferens is rarely visible at the postero- However, knowledge of its location is important to lateral aspect of the prostate but becomes more vis- avoid injury to these vessels during either insertion ible as its course becomes more superficial laterally of the lateral trocars or dissection of the space of as it crosses over the external iliac vessels. Retzius. Again, the vas deferens and the medial umbili- cal ligament are major landmarks for pelvic lymph node dissection: the vertical incision of the parietal Spermatic Cords peritoneum lateral to the medial umbilical liga- ment and posterior to the vas deferens provides the The spermatic cord is formed by the convergence initial access to the obturator fossa. The external of the lymphovascular packet draining the testes, iliac vein can be immediately identified laterally, the vas deferens, the corresponding nerves (the with the external iliac artery located further genital branch of the genitofemoral nerve and the anterolaterally. Spermatic Cords 21 Iliac Vessels The obturator nerve is located posterior and medial to the external iliac vein. It appears as a The external iliac artery is easily recognized pul- white, shining, striated, usually flattened cord that sating below the overlying parietal peritoneum enters the obturator fossa distally. Proximally, fold at the level where the vas deferens joins the it is located at the convergence of the internal and gonadal vessels. external iliac veins. The obturator artery, a primary Lateral to the external iliac artery is the geni- or secondary branch of the internal or even external tofemoral nerve, which can eventually be used iliac artery, usually runs posterior to the obturator for nerve grafting after resection of the prostatic nerve, and the obturator vein is commonly located neurovascular bundle.