Abdominal Imaging

The abdominal radiograph

Why do we see any structure on a normal abdominal radiograph? It has to be surrounded by tissue of different attenuation (x-ray stopping power). we therefore see margins delineated by air (the mucosal surface of air filled bowel) Things outlined by fat (usually the kidneys. the psoas margins,the bladder and the abdominal wall).

We can only see gas soft tissue (effectively water density)- viscera, bowel and bowel wall, bladder. bone and calcium-stones, calcified lymph nodes,stones(90% renal, 10% gallstones) Fat

Properitoneal fat Transversus abdominis

A FEW INTERESTING RADIOGRAPHS

Gas outside the bowel. Outling both the inside and outside of the bowel. Free gas

DILATED LARGE BOWEL WITH NO BOWEL WALL THICKENING Turned out to be a sigmoid tumour.

Gross large bowel wall thickening. Secondary to ulcerative colitis

Causes of colitis Inflammatory bowel disease Ischaemic colitis Pseudomembranous colitis Amoebic,schistosoma etc

Gas outside the bowel. Outling both the inside and outside of the bowel. Free gas

Aortic aneurysm

Basic CT Anatomy

mhv rhv IVC anterior posterior right left

gb rk ra cl (1) stomach anterior posterior right left spleen pv ha

anterior posterior right left rk lk pancreas sv d cd

Fluid in lesser sac gallbladder

Renal pelvis Renal artery Renal vein

uu anterior posterior right left

u u anterior posterior Right left

anterior posterior right left u u bladder nav

Left gastric A Gastroduodenal A Common Hepatic A Splenic A Pancreaticoduodenal A Right gastric –small, from proper hepatic or Lt gastric

Image of an aneurysm to discuss suitability