Myoepithelioma of the hand and carpal tunnel: An unusual cause of median nerve compression.

Myoepitheliomas are rare tumors increasingly recognized to occur in the soft tissues. Although the hand and carpal tunnel are exceptional locations, the presence of these lesions in such sites constitutes a potential cause of debilitating symptoms. We report the case of a patient with severe pain secondary to median nerve compression and displacement of flexor tendons caused by a rapidly growing myoepithelioma. This is the first sonographic description of this tumor producing carpal tunnel syndrome and disabling pain. High-resolution sonography allowed evaluation of gross tumor morphology and real-time assessment of its interactions with surrounding structures.

Percutaneous balloon fenestration and stent placement for lower limb ischemia complicated with type B aortic dissection.

We report a case of lower limb ischemia secondary to type B aortic dissection, which was successfully treated with endovascular aortic fenestration and stent placement. In this case, we were not able to restore adequate flow to the ischemic limb by means of aortic balloon fenestration alone, so additional stent placement was required to buttress the true lumen and fenestra. There was no recurrence of lower limb ischemia complications during the follow-up period. Aortic balloon fenestration with stent placement seems to be a safe and effective technique to salvage an ischemic lower limb complicated by acute aortic dissection.

Use of the wallstent for symptomatic relief of malignant inferior vena cava obstructions.

PURPOSE: To report our experience with the Wallstent for the relief of congestive symptoms in patients with malignant inferior vena cava (IVC) obstructions. MATERIALS AND METHODS: We treated five patients with malignant obstructions of the IVC with a total of seven self-expandable stents. All obstructions were due to extrinsic compression; the procedures were indicated to relieve congestive symptoms in patients unresponsive to other therapies or in whom other treatments were contraindicated. Patients were evaluated for decrease in ascites and edema, weight loss, and patency, where available. RESULTS: All procedures were straightforward and obstructions could be successfully canalized. Inferior venacavograms obtained immediately after the procedure showed complete revascularization and disappearance of collateral circulation. Follow-up was carried out until death in four patients and until discharge in one. Of the five patients, four showed clinical improvement and one had no improvement. There was no recurrence of congestive symptoms. Except for one patient with partial migration of a stent, there were no important complications related to the procedure. CONCLUSION: Wallstents could be placed without complications in the IVC and were effective to ameliorate congestive symptoms in patients with malignant IVC obstructions.

Endovascular obliteration of bleeding duodenal varices in patients with liver cirrhosis.

The purpose of this paper is to describe our experience with endovascular obliteration of duodenal varices in patients with liver cirrhosis and portal hypertension. Balloon-occluded transvenous retrograde and percutaneous transhepatic anterograde embolizations were performed for duodenal varices in five patients with liver cirrhosis, portal hypertension, and decreased liver function. All patients had undergone previous endoscopic treatments that failed to stop bleeding and were poor surgical candidates. Temporary balloon occlusion catheters were used to achieve accumulation of an ethanolamine oleate-iopamidol mixture inside the varices. Elimination of the varices was successful in all patients. Retrograde transvenous obliteration via efferent veins to the inferior vena cava was enough to achieve adequate sclerosant accumulation in three patients. A combined anterograde-retrograde embolization was used in one patient with balloon occlusion of afferent and efferent veins. Transhepatic embolization through the afferent vein was performed in one patient under balloon occlusion of both efferent and afferent veins. There was complete variceal thrombosis and no bleeding was observed at follow-up. No major complications were recorded. Endovascular obliteration of duodenal varices is a feasible and safe alternative procedure for managing patients with portal hypertension and hemorrhage from this source.

Effect of stent oversizing on in-stent stenosis and lumen size in normal porcine veins.

PURPOSE: To present an in vivo evaluation of the effects of stent oversizing on in-stent stenosis and on actual lumen size in normal veins. METHODS: Twelve self-expanding stents were implanted in the common iliac veins of 6 minipigs, which were divided in 2 groups for follow-up at 1 and 3 months, respectively. Oversizing ranged from 119.5% to 216% of the original vessel diameter. Intravascular ultrasound (IVUS) was used to measure vessel areas at the stent edges and midpoint. In-stent stenosis and decrease in actual lumen size were evaluated with IVUS immediately after implantation and during follow-up. RESULTS: There was a very strong positive linear regression between stent oversizing and in-stent stenosis in the 1-month model (r=0.947, p=0.004), in the 3-month model (r=0.931, p=0.007), and in the sum of these 2 groups (r=0.83, p<0.001). Regarding the change in actual lumen size, we found a strong negative linear regression with stent oversizing in the 1-month (r=-0.754, p=0.083) and the 3-month (r=-0.562, p=0.246) groups, but these did not attain statistical significance. However, a strong correlation between stent oversizing and a decrease in lumen size in all samples proved to be statistically significant (r=0.619, p=0.032). CONCLUSIONS: Stent oversizing was strongly correlated with increased in-stent stenosis and decreased actual lumen size at follow-up in normal non-stenotic porcine veins.

Prophylactic stenting of the inferior vena cava before transcatheter embolization of renal cell carcinomas: an alternative to filter placement.

PURPOSE: To report the use of the self-expanding Wallstent as an alternative to prophylactic inferior vena cava (IVC) filter placement before embolization of renal carcinomas with tumor thrombus. CASE REPORTS: Two patients, a 71-year-old man and an 88-year-old woman, were diagnosed with extensive tumor infiltration of the IVC secondary to renal cell carcinomas. Prophylactic placement of an IVC filter before transcatheter embolization was unsuccessful in both cases; a reduced space for deployment would have left part of the filter inside the right atrium. Instead, a Wallstent was used to constrain the tumor thrombus against the vessel wall and, at the same time, protect the patency of the contralateral kidney. Adequate patencies were confirmed 9 months after stenting in the first patient and after 19 days in the second patient. There were no clinical manifestations of pulmonary embolism. CONCLUSIONS: Wallstent implantation is an alternative prophylactic measure before transarterial embolization of renal carcinomas if IVC filters cannot be placed.

Portosplenic blood flow separation in a patient with portosystemic encephalopathy and a spontaneous splenorenal shunt.

A patient with portosystemic encephalopathy, hyperammonemia, and a spontaneous splenorenal shunt was admitted to the authors' institution after a failed attempt at transvenous retrograde shunt obliteration. As an alternative approach, the authors separated splenic and portal flows by embolizing only the proximal splenic vein while leaving the shunt intact. Thus, the splenic flow could escape into the systemic circulation and an extreme increase in portal pressure was avoided. The procedure could provide rapid decreases in blood ammonia levels and a fast resolution of symptoms, but repeated interventions were required.