Evaluation of the LGM Vena-Tech infrarenal vena cava filter in an ovine venous thromboembolism model.

Purpose: To validate a new percutaneous model of venous thrombosis in sheep and evaluate the use of the LGM Vena-Tech vena cava filter with use of this model.

Materials And Methods: After implantation of a LGM Vena-Tech filter in the infrarenal vena cava (IVC), thrombus was obtained by blocking the iliac vein with an inflated balloon (Wedge catheter) for 15 minutes and simultaneously injecting 20 mL of fresh thrombus into the femoral vein. Clot migration of the thrombus was induced by balloon deflation and injection of contrast medium.

[Morphometric study of the wall of the caudal vena cava after the implantation of a filter in the sheep].

The long stabilizers of the VT-LGM filter rest on large areas of the vascular wall. The morphometric study of the layers of the vascular wall, after implantation of filter in 15 ewes, divided into 3 groups of follow-up (2, 4 or 8 weeks) of 5 animals, was made at 3 levels opposite the filter and 1 level outside of it. Changes are seen for all the layers.

Caval incorporation of the LGM Vena Tech filter: an experimental study.

Purpose: To analyze LGM Vena Tech filter incorporation and the rapidity of the process.

Materials And Methods: A filter was inserted into the infrarenal inferior vena cava (IVC) of 15 ewes assigned to one of three groups depending on the length of follow-up (2, 4, or 8 weeks). Radiologic data concerning IVC diameter and filter patency, stability, and incorporation were obtained before and after insertion and before euthanasia.

Plasma treatment effects on the tantalum Strecker stent implanted in femoral arteries of sheep.

Purpose: To evaluate the effects of plasma treatment, a cleaning process for removal of organic contaminants from the knit-wire surface of tantalum Strecker stents, on biocompatibility and thrombogenicity.

Methods: A treated or untreated stent was randomly implanted in both femoral arteries of 15 sheep studied for periods of 4 (group 1), 15 (group 2), or 42 (group 3) days. Patency, histological changes, and mechanical effects were compared by means of radiologic and pathologic controls.

[Comparative study of bioactive calcium phosphate ceramics after implantation in spongy bone in dogs. Histologic, ultrastructural and electron probe microanalysis].

An experimental model of posterior spine arthrodesis in dogs was created using 3 types of calcium phosphate biomaterials already known for their applications as bone substitutes, namely: hydroxyapatite (HA), which is not readily resorbable; highly resorbable tricalcium phosphate (TCP); and a mixture of HA and TCP (BCP), the resorbability of which depends on the proportion of HA and TCP. The BCP implants had a macroporous structure, whilst the HA and TCP implants were used in dense form. The creation of macropores increases the surface exchange area, thus enabling the osseous colonization processes.