Spees W.,CDRH |
Berndt D.,Mapletech Productions LLC
Medical Device and Diagnostic Industry | Year: 2010
A finite state machine-based architecture needs to be identified that can provide an attractive alternative to conventional real-time operating system (RTOS). This need arises as the operation of a multitasking RTOS is difficult to verify completely, and incorrect assumptions about its dynamic operation and side effects could have serious implications. A major benefit of using finite state logic to design software is that it clearly communicates system logic, structure, and organization, both in human-accessible and machine-readable forms. The performance benefit achievable by continuous, concurrent, and direct execution of task state machines is derived from the inherent nature of finite state logic, given a specific state of a system, no action or output processing is required until a specific defined event has occurred.
MacPherson M.,Abraxis BioScience |
Foltz B.,The Good |
Helfgott J.,CDRH |
Singer N.,Compliance Alliance LLC |
Hocker S.,Lindyn Group
Medical Device and Diagnostic Industry | Year: 2010
OEMs which can benefit from the latest resources and current practices for clinical investigation programs are discussed. the medical device development process typically includes developing the product, collecting clinical data or other evidence on the product's safety and effectiveness, and completing a marketing application in the form of a premarket approval (PMA) or premarket notification (510 (k)), which is submitted to FDA. These inspections ensure the quality and integrity of clinical data that are submitted to the center to support marketing applications. The practices identified in this paper related to auditing, monitoring, and training are cost-effective measures for improving the quality of medical companies' new product submissions. These can help to ensure the reliability and integrity of data collected during the clinical trial process, and ultimately safeguards the health of citizens both in the United States and around the world.
Solar Atmospheres Inc., Souderton,Pa., announces that it has become the first company to receive MedAccred critical process re-accreditation. Furthermore, the company expanded its scope of accreditation to include Hardness Testing and Metallography & Microindentation Hardness. MedAccred is an industry-managed critical process supply chain oversight program developed by leading medical device companies to improve device quality and enhance patient safety. The effort to establish MedAccred began in 2010 when the Performance Review Institute (PRI) was asked to consider the development of a Nadcap style special process supplier accreditation program for the medical device industry. An industry roundtable was organized and convened in 2012 among interested medical device companies and PRI. Following this roundtable meeting, briefings were held with the FDA Center for Devices and Radiological Health's (CDRH) Office of Compliance and the FDA's Office of Global Operations within the Office of the Commissioner. The program purpose and scope was discussed, along with the results of proof of concept audits conducted to demonstrate the program's viability. The FDA provided positive feedback and strong encouragement to pursue the development of the program. By 2014, several critical process Task Groups were operating on a formal basis. Program documents were drafted, circulated, and approved by the executives of the participating companies, and audit criteria had been published in several critical process areas. Solar Atmospheres committed to hosting the first MedAccred audit. In early 2015, the first MedAccred critical process accreditation was issued to Solar Atmospheres or Heat Treating. Today's functioning critical process Task Groups include Cable & Wire Harnesses, Heat Treating, Plastics Injection Molding, Printed Circuit Board Assemblies, Sterilization, and Welding. The industry-managed task groups develop audit criteria, conduct audits, and award MedAccred Critical Process Accreditations to leading suppliers at all tiers in the Medical Device Supply Chain. Many companies are seeking MedAccred Accreditation to demonstrate their commitment to quality and patient safety. Future MedAccred Task Groups under consideration for development include Material Testing Laboratories, Assemblies, PCBs, Batteries, Chemical Processing, NDT, Cleaning, Coating, Optics, and Packaging. Active OEM and Contract Manufacturer participants include Johnson & Johnson, Philips, Stryker, GE Healthcare, Medtronic, NYPRO Jabil, Steris, etc. The list of participating suppliers is growing steadily.
Choi M.,CDRH |
Zafar F.,CDRH |
Wang J.,CDRH |
Ramponi G.,University of Trieste |
And 3 more authors.
ACM SIGGRAPH 2013 Posters, SIGGRAPH 2013 | Year: 2013
The luminance range of the sun to the night sky is approximately 14 orders of magnitude. Current display technology can present approximately three orders of magnitude, however this number is increasing as High-Dynamic-Range (HDR) technology develops to further emulate reality [Seetzen et al. 2004]. Another benefit to HDR technology is the increased bit-depth enabling the display of more information. However, a major limitation in the perception of added bit-depth is veiling glare. The increased luminance range in HDR displays have the ability to produce glare sources that can reduce the visible contrast in neighboring dark areas. This effect is especially undesirable in the visualization of scientific data and in medical images. The HDR presentation must be optimized so that the benefits of a wide luminance range are not diminished by glare in the human visual system. One important question is, what is the largest luminance range that avoids these veiling glare effects while presenting the most bit-depth? We have found that the answer is highly dependent on the spatial and luminance distribution in the image. Many models have been proposed to estimate the veiling glare in a given image. A well known model is High-Dynamic-Range Visual Difference Predictor 2 (HDR-VDP- 2) [Mantiuk et al. 2011], a calibrated method able to determine the visibility of differences in HDR images. Building on a number of previous metrics of visible difference, this model operates in a broad range of viewing conditions, from scotopic to photopic vision. More importantly, HDR-VDP-2 can be used to represent the effects of visual glare in signal detection. The inputs of the HDRVDP- 2 are a luminance map of an image, a reference image, and an image with the target. The software outputs the probability of target detection accounting for various visual effects including veiling glare.
Dutta D.K.,CDRH |
Dutta D.K.,Uniformed Services University of the Health Sciences |
Potnis P.A.,CDRH |
Rhodes K.,CDRH |
And 2 more authors.
PLoS ONE | Year: 2015
Multinucleate giant cells (MGCs) are formed by the fusion of 5 to 15 monocytes or macrophages. MGCs can be generated by hip implants at the site where the metal surface of the device is in close contact with tissue. MGCs play a critical role in the inflammatory processes associated with adverse events such as aseptic loosening of the prosthetic joints and bone degeneration process called osteolysis. Upon interaction with metal wear particles, endothelial cells upregulate pro-inflammatory cytokines and other factors that enhance a localized immune response. However, the role of endothelial cells in the generation of MGCs has not been completely investigated. We developed a three-dimensional peripheral tissue-equivalent model (PTE) consisting of collagen gel, supporting a monolayer of endothelial cells and human peripheral blood mononuclear cells (PBMCs) on top, which mimics peripheral tissue under normal physiological conditions. The cultures were incubated for 14 days with Cobalt chromium alloy (CoCr ASTM F75, 1-5 micron) wear particles. PBMC were allowed to transit the endothelium and harvested cells were analyzed for MGC generation via flow cytometry. An increase in forward scatter (cell size) and in the propidium iodide (PI) uptake (DNA intercalating dye) was used to identify MGCs. Our results show that endothelial cells induce the generation of MGCs to a level 4 fold higher in 3-dimentional PTE system as compared to traditional 2-dimensional culture plates. Further characterization of MGCs showed upregulated expression of tartrate resistant alkaline phosphatase (TRAP) and dendritic cell specific transmembrane protein, (DC-STAMP), which are markers of bone degrading cells called osteoclasts. In sum, we have established a robust and relevant model to examine MGC and osteoclast formation in a tissue like environment using flow cytometry and RT-PCR. With endothelial cells help, we observed a consistent generation of metal wear particle- induced MGCs, which heralds metal on metal hip failures. © 2015, Public Library of Science. All rights reserved.