The early diagnosis of acute occlusive mesenteric ischaemia: experimental results and clinical applications.

The diagnosis of acute superior mesenteric artery occlusion in the dog has been achieved in every case by isotope scanning of the abdomen using technetium-labelled red cells or technetium-labelled human serum albumin. The white cell count is also significantly elevated, but the changes in the levels of the enzymes CPK, LDH, AST and serum amylase are not specific for actue mesenteric ischaemia. In the human the presence of a normal gut circulation can be demonstrated by isotope scanning provided that the patient is not severely shocked. The presence of a normal gut circulation as shown on the scintigram conclusively eliminates the possibility of acute main trunk occlusion of the superior mesenteric artery. This should be of help in differentiating acute occulusive mesenteric ischaemia from other causes of the acute abdomen. Abdominal scintiscanning is complementary to angiography, which still remains the most precise means of diagnosing acute mesenteric ischaemia. Although the abdominal scintigram is more limited in its application and is not as accurate as angiography, it is quicker to perform, non-invasive, and entirely safe. Abdominal scintiscanning is an excellent screening test to be used in patients suspected of suffering from acute occlusive mesenteric ischaemia.