Frederick S. Keller

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Gianturco-Rösch expandable Z-stents were used in 22 patients with superior vena cava syndrome (SVCS). Stents were placed in all patients in the SVC and in 17 patients, also into the innominate veins. Stent placement resulted in complete relief of symptoms in all patients. Twenty-one patients had no SVCS recurrence from 1 to 16 months, to their death, or to(More)
A long-term evaluation of a new percutaneously placed bioprosthetic, bicuspid venous valve (BVV) consisting of a square stent and small intestinal submucosa (SIS) covering was performed in 12 sheep. Of 26 BVVs placed into the jugular veins, 25 exhibited good valve function on immediate venography and 22 on venograms obtained before the sheep were killed.(More)
BACKGROUND Most of the presently used percutaneous arterial closure devices (PACD) for hemostasis after interventional vascular procedures are effective, but carry risk of complications by deposition of a foreign body. A new promising externally applied PACD - chitosan-based HemCon Bandage (HCB) was explored in sheep. The HCB hemostatic efficacy and(More)
PURPOSE To retrospectively review the indications and outcomes of transjugular liver biopsy (TJLB) with the left internal jugular vein (IJV) approach. MATERIALS AND METHODS A retrospective review of all TJLBs performed at one institution was performed. From August 1995 to October 2004, 293 liver biopsies were performed. Nineteen of the 293 procedures(More)
Connections between the systemic and pulmonary arterial systems are rare conditions that can be due to either congenital or acquired diseases such as anomalous systemic arterial supply to normal lung, pulmonary sequestration, and systemic supply to pulmonary arteriovenous malformations. Herein, a unique case of systemic artery to pulmonary arterial(More)
OBJECTIVES To eliminate occasional tilting of the original bioprosthetic venous valve (BVV) a second-generation BVV has been developed. This study was performed to evaluate deployment, stability, and short-term function of the second-generation BVV in an animal model. METHODS A second-generation percutaneously placed BVV consisting of a square stent and(More)
Lower extremity chronic deep venous insufficiency (CDVI) is common and remains a major health problem worldwide. Selected patients benefited from direct deep vein valve surgical repair or valve transplantation. A major limitation of this approach is that most of the patients are not candidates for these procedures due to obstructions or residual thrombus(More)
PURPOSE To investigate two spatial orientations of a percutaneously placed bicuspid second-generation bioprosthetic venous valve (SG-BVV) in the jugular vein (JV). MATERIALS AND METHODS Twelve SG-BVVs, consisting of small intestinal submucosa attached to a nitinol frame were placed across a natural valve (NV) in the distal JV in six sheep. Six SG-BVVs(More)
Purpose: In vitro and in vivo evaluation of a new retrievable, home-made, inferior vena cava (IVC) Square stent filter (SSF) with two trapping levels. Methods: In vitro, the SSF was compared in a flow model with the stainless steel Greenfield filter (SGF) for embolitrapping efficiency by serially passing 300 emboli of 3 and 6 mm in diameter and 15–30 mm in(More)
PURPOSE To describe the use of intravascular ultrasound (US) guidance for creation of transjugular intrahepatic portosystemic shunts (TIPSs) in humans. MATERIALS AND METHODS The initial 25 cases of intravascular US-guided TIPS were retrospectively compared versus the last 75 conventional TIPS cases during the same time period at the same institution in(More)