Abdomen Anatomy 2024 PDF.pdf

Abdomen Reference: Bontrager Chapter 3 & Radiographic Positioning & Related Anatomy 11th Edition RAD 101 Abdominal Anatomy Bony structures Abdominal muscles Digestive system Accessory digestive organs Spleen Urinary system Abdominal cavity Qu...

Abdomen Reference: Bontrager Chapter 3 & Radiographic Positioning & Related Anatomy 11th Edition RAD 101 Abdominal Anatomy Bony structures Abdominal muscles Digestive system Accessory digestive organs Spleen Urinary system Abdominal cavity Quadrants & Regions Topographic Landmarks 2024 2  Bony Structures Lumbar Spine Sacrum Coccyx Pelvis Femur 2024 3  Abdominal Muscles Two Psoas Major & Minor Located on either side of the lumbar spine Diaphragm Umbrella-shaped muscle Separates abdominal cavity from thoracic cavity 2024 4  Diaphragm Openings Inferior Vena Cava Hiatus Aortic Hiatus Esophageal Hiatus 2024 5  digestive system 1)Oral cavity 2)Pharynx 3)Esophagus Digestive 4)Stomach System 5)Small intestines 6)Large intestines Accessory organs Liver Gallbladder pancreas Fig. 3.3 2024 6 Stomach & Small Intestine Stomach -Size and shape can vary depending on contents and body habitus Duodenum -Shortest and widest portion -Looks like the letter “C” -Proximal portion is called duodenal bulb or cap -Ducts from liver, gallbladder and pancreas drain into the duodenum Jejunum -2/5 of small intestine Ileum -3/5 of small intestine 2024 Fig. 3.4 7 Stomach & Small Intestine Review Stomach Duodenal Bulb (cap) A - Duodenum (c shaped) B - Jejunum C - Ileum 2024 8  Ducts Connecting to Duodenum 2024 9  Large Intestine Begins in the right lower quadrant at the ileocecal valve Cecum Appendix (Vermiform) is attached at the posteromedial aspect of the cecum Ascending colon Vertical portion of bowel Joins the transverse colon at the right colic (hepatic) flexure Transverse colon Joins the descending colon at the left colic (splenic) flexure Descending colon Sigmoid Fig. 3.6 S-Shaped Rectum Ends at the anus –Sphincter muscle 2024 10 Accessory Pancreas Liver Digestive Organs Gallbladder Accessory Digestive Organs Pancreas Located posterior to stomach Head of pancreas sits in the c-loop of the duodenum (romance of the abdomen) Body and tail into upper left quadrant A part of the endocrine & exocrine system produces insulin to help with blood sugar levels produces digestive juice Fig. 3.7 2024 12 Accessory Digestive Organs Liver Largest solid organ Occupies most of the right upper quadrant Produces bile that assist in emulsification (breakdown) of fats Fig. 3.7 2024 13  Accessory Digestive Organs Gallbladder pear-shaped sac Located posterior and inferior to the liver Bile gets stored and concentrated Contracts and releases bile when the hormone (cholecystokinin, CCK) is Fig. 3.7 released Pathology: Cholelithiasis: presence of one or more calculi (gallstones) in the gallbladder. Only 20% are 2024 visualized on an abdominal image (due to calcium) 14 Spleen Part of the lymphatic system Sits posterior and left of the stomach Located in the left upper quadrant Can be visualized faintly on abdomen images particularly if enlarged (splenomegaly) Fig. 3.7 2024 15  Urinary System Two Kidneys right sits more inferior than the left due to the liver eliminate waste material and excess water from the blood Two Ureters One Urinary Bladder One Urethra Fig. 3.10 2024 Suprarenal (adrenal) glands are located on the superomedial portion of each kidney (a part of the endocrine system) 16  Review Urinary System A. Left kidney B. Left proximal ureter C. Left distal ureter D. Bladder Which kidney sits E. Right kidney lower? Why? 2024 17 Fig. 3.11  Important Terms: Peritoneum Abdominal Parietal Cavity Visceral Mesentery Omentum Mesocolon 2024 18 Peritoneum Double-walled saclike membrane that contains most of the abdominal structures & organs 1. Parietal peritoneum Adheres to the abdominal cavity wall 2. Visceral peritoneum Portion that covers the organs 3. Peritoneal cavity Space between the two portions Contains organs Contains lubricating-type fluid Ascites: abnormal Fig. 3.14 accumulation of fluid in the abdomen 2024 19 Mesentery Double fold of the peritoneum that extends anteriorly from the posterior abdominal wall holds the small intestines in place Fig. 3.14 2024 20  Specific type of double-folded peritoneum that extends from the stomach to another organ Lesser omentum Extends superiorly from the lesser curvature of the Omentum stomach to portions of the Liver Greater omentum Connects the transverse colon to the greater curvature of the stomach inferiorly Drapes over the small bowel, then folds back on itself to form an apron along the anterior wall “fatty apron” 2024 21  The peritoneum that attaches the colon to the posterior abdominal wall 4 forms of mesocolon – named Mesocolon after the portion of the colon they attach to Ascending Transverse Descending Sigmoid (pelvic) 2024 22  Two parts of the peritoneal cavity Greater & Major portion: Lesser Sac Greater sac aka peritoneal cavity Smaller portion: Lesser sac Located in the upper posterior part of the peritoneal cavity behind the stomach Special name: Omentum Bursa Fig. 3.16 2024 23  Where Are Your Organs located? Intraperitoneal - (Within) Retroperitoneal - (Behind) Infraperitoneal - (Beneath or Under) 2024 https://www.ldatschool.ca/wp- 24 content/uploads/2014/07/Mnemonics.jpg Intraperitoneal Organs Liver Organs located within the Gallbladder abdominal cavity that are Spleen partially or completely covered by some type of Stomach visceral peritoneum Jejunum Ileum Cecum Transverse Sigmoid Total of 9 organs 2024 25  Retroperitoneal Organs Structures that are closely attached to the posterior abdominal wall (retro, means “backward” or “behind”) Kidneys Ureters Adrenal glands Pancreas C-loop of duodenum Ascending colon Descending colon Upper rectum Major abdominal vessels Inferior vena cava Aorta 2024 26 Infraperitoneal Organs Located under or beneath the peritoneum 3 total Lower rectum Urinary bladder Reproductive organs 2024 27  Time Out! Cecum (Intra) Ascending (Retro) Transverse (Intra) Descending (Retro) Sigmoid (Intra) Upper Rectum (Retro) Lower Rectum (Infra) 2024 28  Divided by 2 planes Quadrants 1. Transverse plane through the abdomen at the level of umbilicus (L4/L5) 2. Vertical plane – midsagittal plane or midline Four Quadrants 1. Right upper quadrant 2. Left upper quadrant 3. Right lower quadrant 4. Left lower quadrant 2024 29  RUQ LUQ RLQ LLQ Liver Spleen Ascending colon Descending colon Gallbladder Stomach Appendix (vermiform) Sigmoid colon Right colic (hepatic) flexure Left colic (Splenic) flexure Cecum 2/3 of jejunum Duodenum (c-loop) Tail of pancreas 2/3 of ileum Head of pancreas Left kidney Ileocecal valve Right kidney Left suprarenal gland Right suprarenal gland 7 6 5 3 Location of Structures and Organs by Quadrants 2024 30 Regions (9) 1 Right hypochondriac 2 Epigastric 3 Left hypochondriac 4 Right lateral (lumbar) 5 Umbilical 6 Left lateral (lumbar) 7 Right inguinal (iliac) 8 Pubic (hypogastric) 9 Left inguinal (iliac) 31  Planes that Separate Regions Vertical Planes (2) Right and Left Lateral Plane (Midway between MSP & ASIS) Transverse/Horizontal Planes (2) Transpyloric Plane (Level of L1) Transtubercular Plane (Level of L5) 2024 32 Topographic Landmarks Xiphoid process (T9-T10) approximates the superior anterior portion of the diaphragm Inferior costal (rib) margin (L2-L3) used to locate upper abdominal organs such as gallbladder and stomach Iliac crest (L4-L5) most commonly used abdominal landmark level of mid-abdominopelvic region Anterior superior iliac spine (ASIS) (S1-S2) Greater trochanter Same level as symphysis pubis Symphysis pubis Ischial tuberosity 2024 33