Advancing Medical Technology Using FPGAs

Field Programmable Gate Arrays (FPGAs) have dramatically changed the design of medical devices in the past decade. FPGAs offer the flexibility of writing software on a standard microprocessor and the reliability and performance of dedicated hardware. In the design of medical devices that previously required the rigorous design of custom circuits or ASIC design, FPGAs are providing a good alternative at a much lower cost for low to mid-volume medical device design. In this session, we will explore how FPGAs relate to medical device technology including real-time processing of data, high performance image processing, precise control, and code reuse from prototype to deployed device. We will explore how this technology was applied to two devices that improve the success of high-risk surgeries. In the first, FPGA technology is used to monitor blood glucose levels in patients during open-heart surgery. The second example is a device that simulates electrical signals from the human nervous system to train neurophysiologists for events that may happen during surgery. We will explore the impact FPGAs have on design cycles, briefly explore the design process, and compare different programming methodologies including C, VHDL, and LabVIEW. Finally, we will discuss the impact of FPGAs with respect to the 510k process.

Enhancing Video Capsule Endoscopy: Location and Bleeding Detection

Video capsule endoscopy (VCE) is a non-invasive method of visually examining the internal lumen of small intestine for inflammation and bleeding through a wireless camera contained in a small capsule. Currently, VCE technology is limited because it cannot map images to their specific locations in the small bowel. Furthermore, approximately 40% of identified problem areas are false positives, making bleeding difficult to find. Therefore, physicians can only estimate the location of inflammation and bleeding areas based on the elapsed time before performing a wired endoscopy. Our pill camera offers an innovative wireless imaging GPS-like location system, in an easy to swallow pill that accurately identifies and displays bleeding areas within the small intestine through an intuitive user interface, which results in a 50% reduction in clinical times, as well as improved diagnosis for potential investors and providers, thus resulting in a $500 cost reduction in physician fees per patient.

Multi-Angle Lensfree Holographic Imaging for 3-D Cytometry on a Chip

Optical microscopy is an essential tool for many biomedical applications. Although commonly-used in laboratory settings, conventional optical microscopes are bulky and relatively costly to use in resource-limited settings which partially limit their use in point-of-care applications.

Surface Integrity of Magnesum-Calcium Orthopedic Biomaterial Procesed by Dry High-Speed Face Milling

Biodegradable magnesium-calcium (Mg-Ca) implants have the ability to gradually dissolve and absorb into the human body after implantation. The critical issue that hinders the application of Mg-Ca implants is its poor corrosion resistance to human body fluids. A promising approach to tackle this issue is tailoring the surface integrity characteristics of the orthopedic implants to get an appropriate corrosion kinetic. High speed face milling of biodegradable Mg-Ca alloy is used in this study as a possible way to achieve that goal. Polycrystalline diamond inserts are used to avoid material adhesion and likely fire hazards. All the cutting tests are performed without using coolant to keep the manufacturing process ecological. High cutting speed of 40 m/s and 200 μm depth of cut are applied in a broad range of feed values to cover finish and rough cutting regimes. The effect of feed as a key machining parameter which defines the amount and duration of thermo-mechanical load and ultimately provides higher chances for surface integrity changes are investigated.

Fast Real Time Binding for Surface Assays Using VCAT Coupled With SPRI

Microassays can take on the order of 1 to 72 hours due to complete the lack of mixing [1]. Various micromixers have been developed to quicken assay times, but they require bulky external equipment, difficult to fabrication and implementation, or are expensive. Robin Liu et al developed a low cost micromixer based on cavitation microstreaming which is easy to implement and has low power consumption. The device consists of small cavities or vertical cavity acoustic transducers (VCAT) located above a microfluidic chamber such that these small cavities trap air when a solution is injected into the chamber. A piezoelectric transducer (PZT) is then placed above the air cavities and is used to vibrate the air-liquid membrane to produce cavitation microstreaming within the chamber to cause mixing [2].

Thermally Responsive Structures for Gastric Pacing and Other Applications

We report on the development of a polymeric layer consisting of an embedded channel network. The channels are filled with a thermally responsive polymer. The embedded thermally responsive polymer is in solid phase in room ambient, but changes to liquid at physiological body temperature (∼37 °C). This phase change results in the polymer structure changing to a more flexible state. An important application of this polymer layer is its use as a thermally regulated support structure for a gastric pacing electrode, to give some rigidity to the electrode body preferable during implantation surgery, while changing to a more flexible state inside the body as the embedded polymer subsequently melts at physiological temperature. The latter is expected to reduce complications caused by a rigid device.

Design and Research of Interspinous Lumbar Non-Fusion Device

Objective: Long term clinical data showed that lumbar fusion for Lumbar spinal stenosis (LSS) and lumbar disc degeneration (LDD) therapy could change the loads of disc and articular facet and increase the motion of adjacent segments which lead to facet arthropathy and adjacent level degeneration. This study is to design and analyze an interspinous process device (IPD) that could prevent adjacent level degeneration in the LSS and LDD therapy. Method: The IPD was designed based on anatomical parameters measured from 3D CT images directly. The IPD was inserted at the validated finite element model of the mono-segmental L3/L4. The biomechanical performance of a pair of interbody fusion cages and a paired pedicel screws were studied to compare with the IPD. The model was loaded with the upper body weight and muscle forces to simulate five loading cases including standing, compression, flexion, extension, lateral bending and axial rotation. Results: The interbody fusion cage induced serious stress concentration on the surface of vertebral body, has the worst biomechanical performance among the three systems. Pedicle screws and interbody fusion cage could induce stress concentration within vertebral body which leads to vertebral compression fracture or screw loosening. Regarding to disc protection, the IPD had higher percentage to share the load of posterior lumbar structure than the pedicel screws and interbody fusion cage. Conclusion: IPD has the same loads as pedicle screw-rod which suggests it has a good function in the posterior stability. While the IPD had much less influence on vertebral body. Furthermore, IPD could share the load of intervertebral discs and facet joints to maintain the stability of lumbar spine.

Innovative Biomimetic Hybrid Composites to Repair Multifunctional Anatomical Region

The development of biomimetic materials for osteochondral tissue substitution and repair can be the start for a revolution in the classical procedures of orthopaedic surgery. The persisting problems, linked to the absence of a complete functional recovery of the articulation and to the stabilization and protraction of the half-life of an articular prosthesis can be overcome by the new class of osteochondral substitutes. The characteristics of the artificial bone tissue are drastically different from those of the natural one and this is mainly due to the absence of the peculiar self-organizing interaction between apatite crystals and proteic matrix. At this purpose a biomimetic approach was used in which apatitic phases are directly nucleated on different macromolecular matrices, which act as template and induce peculiar physico-chemical features in the mineral phase to create a substitute for osteochondral lesions. In particular a biologically inspired approach was applied to nucleate bone-like hydroxyapatite (HA) nanocrystals on self-assembling collagen fibers. Biohybrid composite materials were obtained mimicking composition, structure and morphology of human osteochondral interfaces. [1–4]

Kinematics of the Posterolateral Corner of the Knee: A Cadaveric Study

Combined injuries of the posterior cruciate ligament (PCL) and the posterolateral corner (PLC) of the knee results in posterolateral rotatory instability. The detailed anatomy and kinematics of the PCL is well described in the literature as well as the anatomy of the PLC; however, the detailed kinematics of the posterolateral corner ligaments and tendons are not well understood. This information on the posterolateral corner is important for developing a strategy for accurate anatomical reconstructions. Therefore, the purpose of this study was to quantify the detailed kinematics of the posterolateral corner of the knee ligaments and tendons.

Software Engineering Practices to Improve Code Quality and Prepare for Validation

Programmers creating mission-critical applications — embedded control applications, industrial monitoring applications, and high-performance test systems — cannot afford to introduce errors or uncertainty into the system. The stakes are especially high in medical applications, where failure can often lead to patient injury and costly product recalls.