Experimental intrahepatic portacaval anastomosis: use of expandable Gianturco stents.

Original Gianturco expandable stents and their modifications were used to create an experimental intrahepatic portacaval anastomosis (EIPCA) in 30 young domestic swine without portal hypertension. The study focused on the design of a suitable stent, the technique of its application, and the evaluation of short-term patency of the EIPCA. A stent with a 2.5-cm-long body and wire skirts on both ends was most suitable for EIPCA creation. Well-positioned stents shunted most of the portal blood in the inferior vena cava circulation and remained patent for 4-6 weeks. Ingrowth of liver parenchyma and abundant proliferation of the intima and connective tissue inside the stent lumen in these rapidly growing animals gradually decreased EIPCA patency, and thrombus formation with diminished blood flow closed them completely.

Iopamidol arteriography: discomfort and pain.

A double-blind, randomized study was performed to compare discomfort and pain associated with the use of iopamidol and Hypaque (diatrizoate sodium and diatrizoate meglumine) during iliofemoral runoff arteriography in 33 patients. Iopamidol caused substantially less discomfort and pain. The evaluation was helped by audiotaping the study and comparing patients' vocal responses to injections of these materials.

The value of protamine following heparin-covered angiography: double-blind placebo-controlled study.

Routine postprocedural administration of protamine sulfate has been advocated to offset the anticoagulant effect of prophylactic heparin given during transfemoral catheter angiography. The value of protamine is shown in a double-blind, randomized, placebo controlled series of 257 cases.

Retrograde pancreatic venography after reduction of the arterial visceral flow: an experimental study.

To evaluate techniques for retrograde pancreatic venography similar to epinephrine renal venography, 35 dogs had transjugular portography before and after the infusion of various doses of vasopressin systemically or selectively into the superior mesenteric and celiac arteries, or after occlusion of the distal thoracic aorta. Increased filling of the peripheral portal branches resulted, but none of the techniques provided diagnostically useful enhanced pancreatic visualization.

Experimental carotid aneurysms: I. Simple surgical production and radiographic evaluation.

Using simple surgical techniques, experimental carotid aneurysms are created which simulate some types of human berry aneurysms, both in hemodynamic and radiographic behavior. End to side anastomoses of an external jugular vein graft to the common carotid artery can be carried out by radiologic personnel with no formal surgical training. Factors which cause the aneurysms to fail and fill with clot are infection, incorporation of venous valves into the aneurysm sac, poor suturing technique, and perhaps a sac too large in comparison with its neck. The models are studied and followed by percutaneous catheter angiography, and show the swirling flow seen in clinical practice. These models may be used to study and refine percutaneous catheter occlusive techniques.