Cross-Sections+of+Abdomen+and+Pelvis

=**Objectives**= toc


 * 1. Review key features of plain films and CT or MRI's of abdomen and pelvis.**

On plain films, the bones are usually the only things that can be easily identified. However, gas in the intestinal loops will appear as dark spots; fecal material or blockages can produce regions of no gas in the intestines.

Barium swallow or enema can be used to visualize the lumen and the positioning of the intestinals and colon. Haustra will be visible in the colon as well as rugae in the stomach. Diverticulums will also show up. Plicae will be higher in the jejunum than in the ilium.

However, be aware that peristalsis alters the shape of the opacities on film.


 * 2. Identify the key landmarks of the abdomen to be used as guides in cross-sectional anatomy of the region.**

The aorta bifurcates into the common iliac arteries around the L5 vertebrae level.


 * 3. Review representative levels of the abdomen and pelvis and identify specific structures listed in the handout at each level.**

**T10**


43 - Esophageal-gastric junction 41 - Fundus of teh stomach 39 - Spleen - Liver 18 - Right-lower lobe of lung 36 - Left-lower lobe of lung 3, 21, 38, 48 - Cut edges of the diaphragm 32 - descending aorta 15 - Inferior vena cava 26 - Azygous vein 26 - Hemiazygous vein

**T12**


4 - Hepatic veins 7 - Proper hepatic artery 10 - Portal vein 8 - Common bile duct - Liver 40 - Stomach 31 - Spleen - Pancreas (not listed in this figure) 32, 33 - Splenic vessels 18, 27- Kidney - Renal cortex (not listed in this figure) - Renal medula (not listed in this figure) 41 - Splenic flexure - Right crus of the diaphragm (not listed in this figure) 25 - Left crus of the diaphragm 23 - Descending aorta 15 - Inferior vena cava

**L1-L2**


3 - Stomach 10 - Duodenum - Liver 8 - Gall bladder 9 - Head of pancreas 42, - Kidney 41 - Renal cortex 42 - Renal medula 52 - Descending colon 59 - Transverse colon 55 - Jejunum 36 - Descending aorta 15 - Inferior vena cava 23 - Psoas 37 - Quadratus lumborum

**L2-L3**


13 - Inferior pole of right lobe of liver 15 - Ascending colon 55 - Transverse colon 43 - Descending colon 52 - Jejunum 36 - Psoas 37 - Quadratus lumborum 7, 8, 9, 54, 53 - Muscles of the anterior abdominal wall 49 - Descending aorta 12 - Inferior vena cava 21 - Ureters

**L4-L5**


5 - Ascending colon 36 - Descending colon 30 - Ilium - gluteusmaximus 14 - gluteus medius

**S5 Male**


17- gluteusmaximus 28 - Rectum 1- Bladder 22 - Obturator internus 53 - Spermatic cord 51 - Femoral artery and vein

**Coccyx Male**


30 - Seminal vesicle 27 - Rectum 58 - Spermatic cord 55 - Femoral artery 55 - Femoral vein 61 - Pubic symphysis

**Lesser trochanter Male**


29 - Anal sphincter 28 - Levator ani 26 - Ischiorectal fossa - Corpora spongiosum 53 - Urethra 59 - Corpora cavernosum 55 - Spermatic cord

**S5 Female**


23 - Rectum - Bladder 34 - Uterus - Cecum 42 - Ileum 17 - Obturator internus 4 - External iliac vessels

**Coccyx Female**


19 - Rectum 1 - Bladder 22 - Uterus 22 - Cervix 30 - Femoral artery 30 - Femoral vein

**Lesser Trochanter Female**


19- Anus 3 - Vagina 2 - Urethra 16 - Ishiorectal fossa 9 - Levator ani 24 - Obturator internus 46 - Pubic symphysis 19 - Anal canal - Crus of the clitoris - Vaginal opening - Urethral opening - Body of the clitoris