Cost-effectiveness of superficial femoral artery endovascular interventions in the UK and Germany: a modelling study.

OBJECTIVES: To assess the lifetime costs and cost-effectiveness of 5 endovascular interventions to treat superficial femoral arterial disease. DESIGN: A model-based health economic evaluation. An existing decision analytical model was used, with updated effectiveness data taken from the literature, and updated costs based on purchasing prices. SETTING: UK and German healthcare perspectives were considered. PARTICIPANTS: Patients with intermittent claudication of the femoropopliteal arteries eligible for endovascular treatment. METHODS: UK and German healthcare perspectives were considered, as were different strategies for re-intervention. INTERVENTIONS: Percutaneous transluminal angioplasty (PTA) with bail-out bare metal stenting (assumed to represent the existing standard of care, and 4 alternatives: primary bare metal stents, drug-eluting stents, drug-eluting balloons (DEBs) and biomimetic stents). PRIMARY OUTCOME MEASURES: The incremental cost-effectiveness ratio between 2 treatments, defined as the incremental costs divided by the incremental quality-adjusted life years (QALYs). RESULTS: Use of a biomimetic stent, BioMimics 3D, was always estimated to dominate the other interventions, having lower lifetime costs and greater effectiveness, as measured by QALYs. Of the remaining interventions, DEBs were always the most effective, and PTA the least effective. There was uncertainty in the cost-effectiveness results, with key drivers being the costs and effectiveness of the biomimetic stent along with the costs of DEBs. CONCLUSIONS: All 4 of the alternatives to PTA were more effective, with the biomimetic stent being the most cost-effective. As there was uncertainty in the results, and all of the interventions have different mechanisms of action, all 4 may be considered to be alternatives to PTA.

An active electrolocation catheter system for imaging and analysis of coronary plaques.

Coronary artery disease-currently one of the most frequent causes of death-is characterized by atherosclerotic plaques grown in the wall of blood vessels and inhibiting blood flow. Preventive assessment focusses on critical sizes of structural plaque parameters like relative lipid core area and cap thickness to identify high-risk plaques called thin cap fibroatheromas. Although state-of-the-art catheter systems were successfully applied in invasive plaque diagnostics, the high costs induced by these devices inhibit usage in daily clinical practice. To overcome this shortcoming, we follow a biomimetic approach to construct a prospective low-cost catheter system that adapts the active electrolocation principles of weakly electric fish Gnathonemus petersii. Only a few and simple parameters relevant for plaque detection and characterization are estimated from plaque-evoked electric images which are projected on the surface of the catheter. Two prototypical electrolocation catheter systems were tested. The first catheter system featured a ring electrode catheter and was used to obtain dynamic 1D electric images of synthetic plaques in an agarose atherosclerosis model. Our proof of concept showed that synthetic plaques could be reliably detected from 1D electric images. Based on a cluster analysis of selected key image features, synthetic plaques could be categorized into four plaque conditions, predefined from thresholds for critical structural parameters, representing high to low risk plaques. In the second recording approach, plaque-evoked dynamic and static spatial electric images were obtained by a multi-electrode catheter system. Based on these recordings, a synthetic plaque with a critical cap thickness could be detected and localized in a pig coronary artery.

Versatile, Reusable, and Inexpensive Ultrasound Phantom Procedural Trainers.

We have constructed simple and inexpensive models for ultrasound-guided procedural training using synthetic ballistic gelatin. These models are durable, leak resistant, and able to be shaped to fit a variety of simulation scenarios to teach procedures. They provide realistic tactile and sonographic training for our learners in a safe, idealized setting.

An anthropomorphic spine phantom for proton beam approval in NCI-funded trials.

As part of the approval process for the use of scattered or uniform scanning proton therapy in National Cancer Institute (NCI)-sponsored clinical trials, the Radiological Physics Center (RPC) mandates irradiation of two RPC anthropomorphic proton phantoms (prostate and spine). The RPC evaluates these irradiations to ensure that they agree with the institutions' treatment plans within criteria of the NCI-funded cooperative study groups. The purpose of this study was to evaluate the use of an anthropomorphic spine phantom for proton matched-field irradiation, and to assess its use as a credentialing tool for proton therapy beams. We used an anthropomorphic spine phantom made of human vertebral bodies embedded in a tissue substitute material called Muscle Substitute/Solid Rigid Number 4 (MS/SR4) comprising three sections: a posterior section containing the posterior surface and the spinous processes, and left and right (L/R) sections containing the vertebral bodies and the transverse processes. After feasibility studies at three institutions, the phantom, containing two thermoluminescent dosimeters (TLDs) for absolute dose measurements and two sheets of radiochromic film for relative dosimetry, was shipped consecutively to eight proton therapy centers participating in the approval study. At each center, the phantom was placed in a supine or prone position (according to the institution's spine treatment protocol) and imaged with computed tomography (CT). The images then were used with the institution's treatment planning system (TPS) to generate two matched fields, and the phantom was irradiated accordingly. The irradiated phantom was shipped to the RPC for analysis, and the measured values were compared with the institution's TPS dose and profiles using criteria of ± 7% for dose agreement and 5 mm for profile distance to agreement. All proton centers passed the dose criterion with a mean agreement of 3% (maximum observed agreement, 7%). One center failed the profile distance-to-agreement criterion on its initial irradiation, but its second irradiation passed the criterion. Another center failed the profile distance-to-agreement criterion, but no repeat irradiation was performed. Thus, seven of the eight institutions passed the film profile distance-to-agreement criterion with a mean agreement of 1.2 mm (maximum observed agreement 5 mm). We conclude that an anthropomorphic spine phantom using TLD and radiochromic film adequately verified dose delivery and field placement for matched-field treatments.

Synthetic human tissue models can reduce the cost of device development.

Synthetic human tissues and body parts that closely resemble the live human environment have been developed for use in medical device verification and validation tests. This article discusses how they can save time and money while improving quality and accuracy.