Branches of the aorta used to be considered vital for the circulation as they often supply a large amount of other vessels. Ligating intercostal or lumbar branches is commonly accepted to be safe if needed. However, the major ventral branches of the aorta were generally thought to be more important. Occlusion of the inferior mesenteric artery (IMA) is being practices routinely ever since the introduction of the endovascular aortic aneurysm repair (EVAR) with often only transient mucosal ischemia of the sigmoid colon observed in about 10% of the cases.
While the occlusion of the superior mesenteric artery (SMA) is widely accepted not to be compatible with life, ligating the celiac axis may be an interesting approach to explore.
Here is a nice and short description of the tests. Rowen Zetterman points out some possible limitations:
"Advanced fibrosis may be underestimated and patients with macronodular cirrhosis may be classified as noncirrhotic.": I don't see this as a problem in real life because macronodular cirrhosis is easily diagnosed just by plain imaging.
"Fibrosis may be overestimated in patients with extrahepatic cholestasis or acute hepatocellular injury due to the effects of these conditions on liver stiffness.": I would add here also CHF as it makes a liver stiff as well.
"Ultrasound elastography does not distinguish patients with no fibrosis from patients with minimal fibrosis.": Yes, this is understandable. But there is probably no clinical relevance of this distinction.
"Ascites can interfere with the generation of a shear wave through the liver.": At the stage of significant ascites, the patients usually have some sort of diagnosis. But I agree that this is a real limitation of the test.
Having those limitations in mind, I think that overall this is a very nice idea. We are challenged now to get some sensitivity and specificity so that we could find the group of patients who could avoid the biopsy.
Recently I had an interesting case with a weird behavior of a suspected metastasis after resection of the primary tumor.
A 43 years old gentleman came in July 2008 to the Medical Service with nausea, vomiting and abdominal pain. The workup showed a tumor in the 3rd portion of the duodenum as well as a big mass in the right liver lobe, so the IM guys asked us to take a look. They performed two attempts to biopsy the masses which showed no tumor. This was the reason for the decision to resect the tumor.
The guys at the Mayo Clinic performed an interesting retrospective study about new-onset diabetes as a marker of underlying pancreatic cancer. They found that approxymately 1% of diabetes subjects aged > or =50 years will be diagnosed with pancreatic cancer within 3 years of first meeting criteria for diabetes.
Especially in patients with a positive family history for pancreatic carcinoma and new-onset of DM, a follow up may be a good idea.