Gross Anatomy of the ABDOMINOPELVIC CAVITY and PERITONEUM M1 Gross and Developmental Anatomy 8:00 AM, November 12, 2008 Dr. Milton M. Sholley Professor of Anatomy and Neurobiology Lymphatic vessels of the testis drain up to lumbar lymph nodes. That is, lymph from the testis drains retrogradely along the pathway of the descent of the testis. Lymphatic vessels of the scrotum drain to the superficial inguinal lymph nodes (just like the rest of the skin of the lower abdomen, thigh, and genitalia). 2 Inferior epigastric vessels Median umbilical fold Medial umbilical fold Obliterated umbilical artery Lateral umbilical fold 3 2 1. Supravesical fossa 1 2. Medial inguinal fossa 3. Lateral inguinal fossa Urachus Posterior view 3 Four abdominal wall flaps will be created by making one vertical cut and one horizontal cut. Position the cuts so that the umbilicus stays with the lower left or the lower right flap. 4 5 Posterior view Grant’s Atlas, 12th ed. Fig. 2.18, p. 1196 Grant’s Atlas, 12th ed. Fig. 2.35D, p. 1367 Grant’s Atlas, 12th ed. Fig. 2.36B, p. 1378 The abdominal and pelvic cavities are continuous. i.e. There is an abdominopelvic cavity. (Sagittal section drawing) 9 (Frontal section drawing) Anterosuperior view Grant’s Atlas, 11th ed. p. 191 P S P False (greater) pelvis is above line PS P True (lesser) pelvis is below line PS P=Promontory of sacrum S=Symphysis of pubis S S Line PS=congugate diameter (Sagittal section drawing) (Sagittal section drawing)10 • The abdominopelvic cavity is lined with parietal peritoneum. • The gut is covered with visceral peritoneum. • Mesenteries are double layers of peritoneum that connect parietal and visceral layers. • The space between parietal and visceral layers is called the peritoneal cavity. Kidney Aorta Dorsal mesentery Parietal peritoneum Visceral peritoneum Peritoneal cavity 11 Intraperitoneal gut • Mesenteries suspend the gut and gut-associated organs within the abdominopelvic cavity. • Mesenteries DO NOT suspend the gut and gut-associated organs within the peritoneal cavity. • The peritoneal cavity normally contains nothing but a small amount of fluid that moistens the surfaces of the peritoneum. • The peritoneal cavity can expand to contain a large amount of fluid under abnormal circumstances. 12 • A retroperitoneal organ is located behind the parietal peritoneum and does NOT have a mesentery. –A secondarily retroperitoneal organ had a mesentery early in embryological life but lost it during further development. –A primarily retroperitoneal organ develops in a retroperitoneal position and never had a mesentery. • An intraperitoneal organ is invested by visceral peritoneum and has a mesentery. 13 14 15 Cross-section at L3-L4 Vertebral Level Right Left Rotated image from: CT-orientation 16 17 Gross Anatomy of the ABDOMINOPELVIC CAVITY and PERITONEUM Part 2 M1 Gross and Developmental Anatomy 9:00 AM, November 12, 2008 Dr. Milton M. Sholley Professor of Anatomy and Neurobiology Mid-sagittal section Walk around the Greater Sac of the Peritoneal Cavity 19 Grant’s Atlas, 12th ed. Grant’s Atlas, 12th ed. Fig. 3.14A, p. 209 Fig. 3.13A, p. 208 20 Pelvic Recesses of the Peritoneal Cavity Rectouterine pouch (Pouch of Douglas) Rectovesical pouch Vesicouterine pouch Grant’s Atlas, 12th ed. Male Female Grant’s Atlas,21 12th ed. Fig. 3.14B, p. 209 Fig. 3.13A, p. 208 Fluid within the Peritoneal Cavity will drain to Low Regions Grant’s Dissector, 12th ed. Fig. 3.28, p. 64 Patient Upright- Patient Supine- Fluid drains to peritoneal pouches Fluid drains to hepatorenal pouches in pelvic cavity and peritoneal pouches in pelvic cavity22 • The male peritoneal cavity is completely closed off from the outside surface of the body. • The female peritoneal cavity is connected to the outside of the body by the openings of the two Fallopian tubes. • The fact that the female peritoneal cavity communicates with the outside of the body is demonstrated by the hysterosalpingogram shown below. 23 Mid-sagittal section Walk around the Greater Sac of the Peritoneal Cavity 24 25 26 Cross-section at L1 Vertebral Level Right Left Rotated image from: CT-orientation 27 28 29 30 31 32 Cross-section at L3-L4 Vertebral Level Right Left Rotated image from: CT-orientation 33 Fluid within the Peritoneal Cavity will drain to Low Regions Grant’s Dissector, 12th ed. Fig. 3.28, p. 64 Patient Upright- Patient Supine- Fluid drains to peritoneal pouches Fluid drains to hepatorenal pouches in pelvic cavity and peritoneal pouches in pelvic cavity34 Superior Right Left Anterior View - In situ orientation 35 Superior Left Right Posterior View - In situ orientation 36 37 38 Superior Right Left 39 Inferior margin flipped upward-Posterior surface viewed from the front 40 41 Cross-section at L3-L4 Vertebral Level Right Left Rotated image from: CT-orientation 42 43 44 45 46 47 48 49 Cross-section at L1 Vertebral Level IVC Aorta Right Left Rotated image from: CT-orientation 50.