Sheep models for evaluation of novel patch and prosthesis material in vascular surgery: tips and tricks to avoid possible pitfalls.

Background: In vascular surgery, novel synthetic prosthesis materials for patch-angioplasties, interpositions, bypasses and shunts are continuously under development and optimization. The characteristics of an ideal vascular prosthesis would display long-term patency, biocompatibility, durability, low porosity, lack of stich hole bleeding, ease of handling, kink resistance, infection resistance and reasonable costs. The aim of this study was to establish and report a reliable sheep model including potential pitfalls where those parameters could be analyzed.

In vivo MRI visualization of parastomal mesh in a porcine model.

Introduction: After two-dimensional plane MRI-visible mesh implants could be successfully visualized in phantom and small animal model, the aim of the underlying study was to explore the feasibility of an MRI visualization of complex three-dimensional mesh geometry in close contact to the intestine. We therefore used a MR-visible three-dimensional intra-peritoneal stoma (IPST) mesh in a porcine model.

Materials And Methods: Laparoscopic terminal sigmoid colostomy has been done with implantation of a prophylactic MRI-visible IPST mesh in two animals.

Wireless blood pressure monitoring with a novel implantable device: long-term in vivo results.

Purpose: Devices constantly tracking the blood pressure (BP) of hypertensive patients are highly desired to facilitate effective patient management and to reduce hospitalization. We report on experiences gathered in a pilot study that was designed to evaluate the prototype of a newly developed, minimally invasive implantable sensor system for long-term BP monitoring.

Methods: The device was implanted in the femoral artery (FA) of 12 sheep via standard FA catheterization under fluoroscopic control.

Superselective particle embolization enhances efficacy of radiofrequency ablation: effects of particle size and sequence of action.

Purpose: To evaluate the effects of particle size and course of action of superselective bland transcatheter arterial embolization (TAE) on the efficacy of radiofrequency ablation (RFA).

Methods: Twenty pigs were divided into five groups: group 1a, 40-μm bland TAE before RFA; group 1b, 40-μm bland TAE after RFA; group 2a, 250-μm bland TAE before RFA; group 2b, 250-μm bland TAE after RFA and group 3, RFA alone. A total of 40 treatments were performed with a combined CT and angiography system.