Gastric bubble under the left dome of diaphragm is one of the commonest appearances; occasionally a subtle tumour can be sometimes seen.
Interposition of the hepatic flexure between the liver and the right dome diaphragm is a normal variant; below the left dome the gastric bubble and sometimes the splenic flexure are visible.
Free air under the diaphragm {pneumoperitoneum] is probably the most important of pathology that should not be missed as this finding may be very subtle.
Pathology of the liver,
gall bladder,
spleen,
pancreas {including calcifications},
aortic may be visible below the diaphragm and may point towards lesions mimicking chest symptoms or other systemic pathology.
The diaphragm a muscular and fibrous tissues separating the thoracic from the abdominal cavity
The area below the domes of diaphragm on the Chest Radiographs is one of the areas of review whilst reporting as a large number of abnormalities can be detected,
point towards underlying disorders that may mimic chest symptoms.
Normal densities below the diaphragm:
The solid organs,
liver and spleen are of low optical density and appear as white on CXR.
Air filled structures like the stomach and large bowel are of high optical density and appear as black on CXR
Calcifications in a cyst are usually round or oval in appearance seen in the solid organs.
Perhaps,
the most important of all is the free air outside the bowel,
the feature of a perforated bowel { also seen in the immediate post operative period}; free air is well seen in most cases,
however it can be subtle in few can be easily missed during routine reporting.
HEPATO-BILIARY: Calcified cysts & granulomas,
hepatomegaly,
pneumobilia,
biliary stents,
surgical clips,
abscess
SPLENIC: Calcified cysts & granulomas,
splenomegaly
PANCREATIC: Calcifications
GASTROINTESTINAL: Stomach{distension,
tablets,
foreign bodies,
gastric banding}large bowel{ dilatation,
toxi megacolon
MISCELLANY: Surgical sutures,
stents {biliary,vascular}