RÉSUMÉ
In this paper, all the intrahepatic arterioportal shunts (IHAPSs) that result from the functional redistribution of hepatic arterial and portal venous blood flow are defined as functional IHAPSs (F-IHAPSs) so as to make the differentiation from organic IHAPSs (O-IHAPSs) that result from the intrahepatic arterioportal fistula or direct communication, such as those IHAPSs that are associated with advanced hepatocellular carcinoma (HCC) and other malignant hepatic tumors as well as those IHAPSs that are accompanied by congenital hepatic vascular malformations, hereditary hemorrhagic telangioectasia (HHT) and liver trauma (including iatrogenic injury), etc. In F-IHAPSs, the most common one is formed by the compensatory (or secondary) increase of arterial blood flow that is caused by the decrease of hepatopetal portal blood flow due to a variety of reasons; its formation mechanisms can be divided into three categories:(1) trans-sinusoidal type, such as the F-IHAPSs that is associated with cirrhosis;(2) post-sinusoidal type, such as the F-IHAPSs that is accompanied with the acute stage of Budd-Chiari syndrome; and (3) pre-sinusoidal type, such as the F-IHAPSs that occurs along with the gastrointestinal hemorrhagic shock. Another kind of F-IHAPSs has been commonly seen in some hepatic diseases that have primary increase of hepatic arterial blood flow, including hypervascular hepatic cavernous hemangioma, small hepatocellular carcinoma that has rich blood supply, hepatobiliary inflammatory diseases, etc.;and in this paper they are all classified as F-IHAPSs category, however, the formation mechanisms of such F-IHAPSs vary with their basic diseases. Clinically, imaging diagnosis of F-IHAPSs can be made based on the following three signs:(1) all kinds of hepatic diseases that have concomitant intrahepatic arterioportal fistula or direct communication, as mentioned above, have been definitely excluded:(2) hepatic artery DSA reveals early visualization of portal vein in arterial phase, known as the characteristic sign of F-IHAPSs;and/or: (3) hepatic dynamic enhanced CT/MR scanning demonstrates transient enhancement of liver parenchyma in arterial phase, especially early visualization of portal vein is also present; in this case the diagnosis of F-IHAPSs can be undoubtedly confirmed. However, in making differential diagnosis, F-IHAPSs must be carefully differentiated from O-IHAPSs, local hepatic parenchymal perfusion caused by hepatic aberrant vein or by abnormal hepatopetal draining vein from systemic circulation, etc. In addition, when cirrhosis-related transient hepatic parenchymal enhancement presents as a solitary small nodule, differentiation with small HCC should be taken into consideration. In order to provide the readers with a complete and up-to-date understanding of F-IHAPSs, the relevant example illustrations, figures and graphics are accompanied with the text.
RÉSUMÉ
This paper aims to make a comprehensive review about the new generation drug-eluting stents and their effects of anti-thrombosis to decrease stent thrombosis (ST), which are very helpful for interventional radiologists, especially for cardiologists who are engaged in percutaneous coronary interventional therapy. Based on the review of recently published academic papers and the investigation of the manufacturers and market of stent, the main factors related to ST complication which is associated with new generation drug-eluting stents are retrospectively and briefly analyzed. Besides, a variety of new generation drug-eluting stents with anti-thrombosis effect that are being successfully developed recently with new technology and new materials, including the renewal or improvement of the stent platform, loaded drug, carrier and its loading technology, etc. are comprehensively described in this paper in a combination way of vivid pictures with corresponding essay. In addition, the development and the prospect in clinical application of biodegradable drug-eluting stents are also briefly discussed in this paper.
RÉSUMÉ
Objective To further explore the blood supply and interventional therapy of adult cavernous hemangiomas of the liver (CHL).Methods Recently some authors reported that a satisfactory effect resulted from transcatheter portal venous embolization was obtained in few cases of CHL with blood supply of portal vein,and raised an objection to the standpoint that CHL was commonly supplied by hepatic artery completely.In order to get a scientific and reasonable explanation for it,this paper reviewed the vascular embryology and histology of the liver,the pathologic features of CHL as well as the relative literature,and combined with the investigation results of blood dynamic changes of CHL that had been performed in 2000～2002 by us.Results CHL was caused by the arrested development of hepatic sinusoids at the embryonic stage.Pathologically,CHL was consisted of a lot of enlarged abnormal sinusoids,which were variant in size and closely related with the hemodynamic changes of CHL (in inverse proportion).The CHL consisted of even and tiny abnormal sinusoids (diameter less than 50 ?m) pathologically usually presented a high flow.During the hepatic artery angiography or CTHA,it was rapidly filled by the arterial blood containing contrast media and frequently showed dense opacification or enhancement.Simultaneously this could result in increased pressure of abnormal sinusoids.When the sinusoidal pressure exceeded that of the connecting portal venules,the arterial blood containing contrast media filled in the abnormal sinusoids could lead to retrograde flow in the portal venules.That was arterial-portal venous shunts (APVS).These appearances described as above could also occur in some CHL with intermediate flow,in which many tiny abnormal sinusoids located in the peripheral area were identified pathologically.On the contrary,the CHL consisted of larger abnormal sinusoids (diameter more than 500 ?m) pathologically usually presented a low flow.During the hepatic artery angiography or CTHA,it was filled very slowly by the arterial blood containing contrast media and was difficult to opacify or enhance.Simultaneously this could result in a low pressure of abnormal sinusoids.When the sinusoidal pressure was lower than that of the connecting portal venules,the portal venous blood containing contrast media could easily flow into the abnormal sinusoids and make it enhanced during the direct or indirect portography (or CTAP).Conclusion CHL is really a congenital venous malformation.All the CHL with high flow and some CHL with intermediate flow are surely supplied by the hepatic artery and drained primarily by the peripheral branches of portal vein.However,in few CHL with marked lower flow,the portal vein should become a primary supply vessel,so a direct or indirect portography (or CTAP) must often be taken to identify the diagnosis.Thereby,the technique of transcatheter embolization of CHL including the aim,indication,approach,and the used sclerotic or embolic drugs,etc,should also be reconsidered in order to improve its therapeutic efficacy.