GIT - Peritoneal Cavity ANAT30008 2024 PDF

Peritoneal Cavity Dr Rex Barton-Smith BSc (Clin Sci), MHSc (Osteo), Grad.Cert.Tert.Ed 1  Learning Outcomes Define what peritoneum is and its functions Understand and describe the development of the peritoneal tissues and the peritoneal...

Peritoneal Cavity Dr Rex Barton-Smith BSc (Clin Sci), MHSc (Osteo), Grad.Cert.Tert.Ed 1  Learning Outcomes Define what peritoneum is and its functions Understand and describe the development of the peritoneal tissues and the peritoneal cavity Describe visceral relationships to peritoneum Identify specific peritoneal tissues from multiple planes and views Describe peritoneal attachments to musculoskeletal and visceral structures Comprehend basic clinical examples relating to the peritoneum 2  Peritoneum Recap Peritoneum - What is it? Continuous transparent serous membrane lining viscera and walls in the abdominal and pelvic regions Peritoneal Tissue and Divisions to comprehend Visceral and parietal peritoneum o These layers formed during embryological development of viscera o Note the difference in innervation and vascular supply Peritoneal connections - ‘omenta, ligaments and mesentery’ o These tissues form connections between peritoneal tissue typically o Double layered o Permit neurovascular supply and provide attachment Peritoneal Cavity and Divisions to comprehend P. Cavity - potential space between parietal and visceral layers Peritoneal fluid lines the parietal and visceral layers/fills the cavity Greater sac and lesser sac are divisions of the cavity 3 Drake RL, Vogl AW, Mitchell AWM. Gray’s Anatomy for Students. 3rd Ed. Churchill Livingstone Elsevier, 2015 Fig 4.1 Parietal peritoneum Visceral peritoneum 4 Drake RL, Vogl AW, Mitchell AWM. Gray’s Anatomy for Students. 3rd Ed. Churchill Livingstone Elsevier, 2015 Fig 4.54  Peritoneal Development Embryological development of viscera results in some viscera moving away from the abdominal wall and dragging peritoneal tissue with it. These viscera that migrate are now: Visceral peritoneum → Surrounded by visceral peritoneum → Referred to as intraperitoneal → Attached to the abdominal wall via peritoneal tissues Parietal peritoneum The viscera remaining on the posterior abdominal wall are now: → Partially covered by peritoneum → Referred to as retro/extraperitoneal 5 Drake RL, Vogl AW, Mitchell AWM. Gray’s Anatomy for Students. 3rd Ed. Churchill Livingstone Elsevier, 2015 Fig 4.52a-b  Retroperitoneal Viscera These are retroperitoneal throughout their development and are paired viscera Suprarenal glands Kidneys and ureters 6 3D4Medical Ltd (2021) Complete anatomy (8.0.0) (Computer App)  Secondarily Retroperitoneal Viscera These viscera became ‘intra’ during development and finished ‘retro’. They are unpaired viscera. Duodenum Pancreas Ascending colon Descending colon 7 Drake RL, Vogl AW, Mitchell AWM. Gray’s Anatomy for Students. 3rd Ed. Churchill Livingstone Elsevier, 2015 Fig 4.52b 3D4Medical Ltd (2021) Complete anatomy (8.0.0) (Computer App) Secondarily Retroperitoneal Development Descending Colon Example 8 Moore KL, Dalley AF & Agur AMR. Clinically Oriented Anatomy. 7th Ed. Wolters Kluwer, 2014, Fig 2.24  Secondarily Retroperitoneal Development Drake RL, Vogl AW, Mitchell AWM. Gray’s Anatomy for Students. 3rd Ed. Churchill Livingstone Elsevier, 2015 Fig 4.6 9 Drake RL, Vogl AW, Mitchell AWM. Gray’s Anatomy for Students. 3rd Ed. Churchill Livingstone Elsevier, 2015 Fig 4.6  Intraperitoneal Viscera Intraperitoneal viscera remain within layers of peritoneum after development. Stomach Spleen Liver and gall bladder Jejunum, ileum and appendix Transverse colon Sigmoid colon They connect to surrounding structures via Omenta ‘Ligaments’ Mesentery 3D4Medical Ltd (2021) Complete anatomy (8.0.0) (Computer App) 10 Intraperitoneal Viscera Liver and small intestine faded 11 3D4Medical Ltd (2021) Complete anatomy (8.0.0) (Computer App) Netter, FH. Atlas of Human Anatomy. 3rd Ed. New Jersey, Icon Learning Systems Plate #266  Peritoneal Tissue Connections Double layered peritoneal connections 1. Mesentery Connect viscera with abdominal wall Embryologically we begin with ventral and dorsal mesentery Our focus will be on the intestinal mesentery 2. Omenta connect stomach and proximal duodenum with other viscera 3. Peritoneal ‘ligaments’ Connect viscera with another viscera or abdominal wall Note the ‘omenta’ are comprised of peritoneal ligaments 12 Drake RL, Vogl AW, Mitchell AWM. Gray’s Anatomy for Students. 3rd Ed. Churchill Livingstone Elsevier, 2015 Fig 4.6  13 Drake RL, Vogl AW, Mitchell AWM. Gray’s Anatomy for Students. 3rd Ed. Churchill Livingstone Elsevier, 2015 Fig 4.13a-d  Peritoneal reflections Mesentery Mesos – ‘middle’ in Greek Enteron – ‘gut/intestine’ in Greek ‘The Mesentery’ – jejunum and ileum Extends to appendix and potentially caecum Transverse mesocolon – transverse colon Sigmoid mesocolon – sigmoid colon 14 Netter, FH. Atlas of Human Anatomy. 3rd Ed. New Jersey, Icon Learning Systems Plate #266  Mesenteries Transverse colon Transverse mesocolon “The mesentery” Sigmoid mesocolon Sigmoid colon Mesoappendix Jejunum and ileum Appendix 15 Moore KL, Dalley AF & Agur AMR. Clinically Oriented Anatomy. 7th Ed. Wolters Kluwer, 2014, Fig 2.25 Netter, FH. Atlas of Human Anatomy. 3rd Ed. New Jersey, Icon Learning Systems Plate #263  Mesentery Root of ‘the mesentery’ Begins at the duodenal flexure Passes obliquely and inferiorly to finish in the lower right quadrant near the ileocaecal junction Root of transverse mesocolon Begins at the hepatic/right colic flexure Passes horizontally over abdominal viscera to finish at the splenic/left colic flexure Root of sigmoid mesocolon Begins at the pelvic brim adjacent to the left common iliac vessels What specific structures do you Passes into the pelvis to finish at the rectum notice each mesentery reflects away from? 16 Netter, FH. Atlas of Human Anatomy. 3rd Ed. New Jersey, Icon Learning Systems Plate #266  Omenta - Greater Omentum Omentum – ‘Apron’ in latin GO reflected superiorly Attachments Greater curvature and proximal duodenum Transverse colon, spleen and diaphragm Key features Double layer folds back upon itself Important pathway for neurovasculature Highly variable in distribution and fat content 17 Netter, FH. Atlas of Human Anatomy. 3rd Ed. New Jersey, Icon Learning Systems Plate #261A and B  Greater Omentum Development Moore KL, Dalley AF & Agur AMR. Clinically Oriented Anatomy. 7th Ed. Wolters Kluwer, 2014, Fig 2.29 McMinn RMH. Last’s Anatomy. 9th Ed. Elsevier, 1994, Fig 5.16 18  Greater Omentum - Ligaments Ligaments Reflections Gastrophrenic ligament Gastrosplenic ligament Gastrocolic ligament 19 Netter, FH. Atlas of Human Anatomy. 3rd Ed. New Jersey, Icon Learning Systems Plate #266 Moore KL, Dalley AF & Agur AMR. Clinically Oriented Anatomy. 7th Ed. Wolters Kluwer, 2014, Fig 2.26  Greater Omenta Donor Variation 20 Rohen JW & Yokochi C, Color Atlas of Anatomy, A Photographic Study of the Human Body. 7th Ed. Lippincott Williams & Wilkins 2010 p306 Rohen JW & Yokochi C, Color Atlas of Anatomy, A Photographic Study of the Human Body. 7th Ed. Lippincott Williams & Wilkins 2010 p292  Omenta – Lesser Omentum Omentum – ‘Apron’ in latin Gastrohepatic ligament Attachments Lesser curvature and proximal duodenum Visceral surface of the liver Hepatoduodenal ligament Key features Important pathway for neurovasculature Houses the portal triad Less variable than greater omentum 21 Netter, FH. Atlas of Human Anatomy. 3rd Ed. New Jersey, Icon Learning Systems Plate #267A  Omenta – Lesser Omentum Gastrohepatic ligament Hepatoduodenal ligament What structures have been removed in this image? 22 Netter, FH. Atlas of Human Anatomy. 3rd Ed. New Jersey, Icon Learning Systems Plate #267A Netter, FH. Atlas of Human Anatomy. 3rd Ed. New Jersey, Icon Learning Systems Plate #280  Peritoneal Ligaments - Liver Falciform ligament Falciform ligament Anterior coronary ligament Left triangular ligament Bare Area *HG Right triangular *HG ligament *HD Lesser Omentum* HG – hepatogastric ligament *HD HD – hepatoduodenal ligament Posterior coronary ligament 23 Netter, FH. Atlas of Human Anatomy. 3rd Ed. New Jersey, Icon Learning Systems Plate #280 Peritoneal Ligaments - Spleen Gastrosplenic ligament Splenorenal ligament 24  Peritoneal cavity – Greater and Lesser Sacs Abdominal viscera largely fill the abdominal cavity The small remaining space between the visceral and parietal peritoneal layers is known as the ‘peritoneal cavity’ The peritoneal cavity can be subdivided into greater and lesser sacs The lesser sac is also referred as the omental bursa Epiploic/Omental foramen is the junction where 25 the greater and lesser sac meet/communicate Drake RL, Vogl AW, Mitchell AWM. Gray’s Anatomy for Students. 3rd Ed. Churchill Livingstone Elsevier, 2015 Fig 4.53  Omental foramen and Lesser Sac/Omental Bursa 26 Moore KL, Dalley AF & Agur AMR. Clinically Oriented Anatomy. 7th Ed. Wolters Kluwer, 2014, Fig 2.29 Netter, FH. Atlas of Human Anatomy. 3rd Ed. New Jersey, Icon Learning Systems Plate #264 Omental foramen and Lesser Sac/Omental Bursa 27 Rohen JW & Yokochi C, Color Atlas of Anatomy, A Photographic Study of the Human Body. 7th Ed. Lippincott Williams & Wilkins 2010 p311  Peritoneal Cavity – Sacs and Omental Foramen Use this slide and the previous two to see if you can work out the boundaries of the omental foramen (anterior, posterior, superior and inferior) 28 Moore KL, Dalley AF & Agur AMR. Clinically Oriented Anatomy. 7th Ed. Wolters Kluwer, 2014, Fig 2.23