Sung Bum Cho

Comparison of a new polytetrafluoroethylene-covered metallic stent to a noncovered stent in canine ureters.

The aim of this study was to determine the feasibility of using a newly designed polytetrafluoroethylene (PTFE)-covered metallic stent in the ureter by comparing its effectiveness with that of the noncovered stent in a canine model. We placed 14 stents in the ureters of seven mongrel dogs that weighed 30–40 kg each. The covered and noncovered stents were deployed in the right and left ureters, respectively, of six dogs. In the seventh dog, a covered stent and a double-J catheter were inserted in the right ureter, and a covered stent only was inserted in the left ureter. The first six dogs were sacrificed at 5, 10, and 15 weeks after deployment of the stents (two for each follow-up period), and the seventh dog was sacrificed at 30 weeks. There was no migration or poor expansion of any of the stents observed on plain radiography. On intravenous pyelogram and retrograde pyelogram, all of the covered stents at each follow-up period had patent lumens at the stented segments without hydronephrosis, and the passage of contrast material through it was well preserved. The noncovered stents in the dogs sacrificed at 5 and 10 weeks and one of the two dogs sacrificed at 15 weeks showed near-complete occlusion of the stent lumen due to ingrowth of the soft tissue, and severe hydronephrosis was also noted. The noncovered stent in the other dog sacrificed at 15 weeks showed the passage of contrast material without hydronephrosis, but the lumen of the stent was still nearly occluded by the soft tissue. There was no evidence of hydronephrosis or passage disturbance of the contrast material in both ureters of the dog sacrificed at 30 weeks. We conclude that the newly designed PTFE-covered stent effectively prevented the luminal occlusion caused by urothelial hyperplasia compared to the near-total occlusion of the noncovered stents, and no migration of the covered stents was noted.

Traumatic Axillary Artery Dissection with Radial Artery Embolism

This report describes a case of pathologically proven traumatic arterial dissection, presenting as complete occlusion of the axillary artery with radial artery embolism. Occlusion of the axillary artery by traumatic dissection mimicked transection and radial artery embolism mimicked congenital absence of the radial artery on the initial angiogram, but these were correctly diagnosed with the following sonogram.

Concurrent inferior vena cava and hepatic vein stenoses after orthotopic liver transplantation: a case report.

Outflow obstruction or stenosis of a hepatic graft is a rare but serious complication after liver transplantation, with a reported incidence of 1% to 6%. It can cause signs of portal hypertension, renal dysfunction, or lower-extremity edema depending on the level of obstruction, which may lead to patient mortality. Most reported cases show a stenosis at either the inferior vena cava (IVC) or one of the hepatic veins. Herein we have reported our experience of concurrent suprahepatic IVC and hepatic vein stenoses after orthotopic liver transplantation with related imaging findings and a successful treatment outcome. Due to the complexity of stenoses, two self-expandable metallic stents were placed simultaneously using different venous accesses.