Southwest Research Institute assistance to NASA in biomedical areas of the technology utilization program Final report, 1 Feb. 1969 - 24 Aug. 1970

Research progress in technology transfer by NASA Biomedical Application Tea

Vascular implants – new aspects for in situ tissue engineering

Conventional synthetic vascular grafts require ongoing anticoagulation, and autologous venous grafts are often not available in elderly patients. This review highlights the development of bioartificial vessels replacing brain-dead donor- or animal-deriving vessels with ongoing immune reactivity. The vision for such bio-hybrids exists in a combination of biodegradable scaffolds and seeding with immune-neutral cells, and here different cells sources such as autologous progenitor cells or stem cells are relevant. This kind of in situ tissue engineering depends on a suitable bioreactor system with elaborate monitoring systems, three-dimensional (3D) visualization and a potential of cell conditioning into the direction of the targeted vascular cell phenotype. Necessary bioreactor tools for dynamic and pulsatile cultivation are described. In addition, a concept for design of vasa vasorum is outlined, that is needed for sustainable nutrition of the wall structure in large caliber vessels. For scaffold design and cell adhesion additives, different materials and technologies are discussed. 3D printing is introduced as a relatively new field with promising prospects, for example, to create complex geometries or micro-structured surfaces for optimal cell adhesion and ingrowth in a standardized and custom designed procedure. Summarizing, a bio-hybrid vascular prosthesis from a controlled biotechnological process is thus coming more and more into view. It has the potential to withstand strict approval requirements applied for advanced therapy medicinal products

Pneumatic Actuator Development for MRI Robots

The Linear Pneumatic-Hydraulic MRI Robot Actuator was designed as a modular solution to precision motion in a medical MRI environment. The implementation of this non-ferrous and nearly completely non-metallic linear driver mechanism gives an operator the ability to place grippers, sensors, syringes, and other medical instruments with an extraordinary level of flexibility and precision. Its modular design allows for rapid prototyping of robotic systems and paves the way for more advanced and complex minimally invasive procedures under real-time MRI guidance. This enables decreased setup and adjustment time as well as higher precision and reduced complications. The team\u27s design will be used in future MRI robot designs and research in collaboration with the UMass Medical School

Front-End Receiver Architecture for Miniaturised Ultrasound Imaging

Abstract -The design and measured results for an I/Q synthetic aperture beamforming front-end are presented. The system targets a highly portable ultrasound imaging applications such as wearable/portable devices and capsule endoscopes. Synthetic aperture beamforming is carried out in the baseband in order to minimise the bandwidth and power consumption. A single-channel analogue front-end (AFE) demodulates RF signals into I/Q components. The FPGA-based beamformer dynamically apodises and focuses the data by interpolating and applying complex phase rotations to the I/Q samples. The entire system is pipelined using a synthetic aperture protocol through a single, multiplexed channel in order to reduce the cost and complexity of the system and minimise the area. The AFE consumes 7.8mW and occupies 1.5 mm × 1.5 mm in AMS 0.35µm CMOS. The digital beamformer is implemented on a Kintex-7 TM FPGA and consumes 262mW for a frame rate of 4Hz. Measured results using real ultrasound data reveal that comparable image quality may be attained to the case when full RF beamforming is used. Future work includes integration of analogue/digital components on a single chip

Technology applications

A summary of NASA Technology Utilization programs for the period of 1 December 1971 through 31 May 1972 is presented. An abbreviated description of the overall Technology Utilization Applications Program is provided as a background for the specific applications examples. Subjects discussed are in the broad headings of: (1) cancer, (2) cardiovascular disease, (2) medical instrumentation, (4) urinary system disorders, (5) rehabilitation medicine, (6) air and water pollution, (7) housing and urban construction, (8) fire safety, (9) law enforcement and criminalistics, (10) transportation, and (11) mine safety

A Three – tier bio-implantable sensor monitoring and communications platform

One major hindrance to the advent of novel bio-implantable sensor technologies is the need for a reliable power source and data communications platform capable of continuously, remotely, and wirelessly monitoring deeply implantable biomedical devices. This research proposes the feasibility and potential of combining well established, ‘human-friendly' inductive and ultrasonic technologies to produce a proof-of-concept, generic, multi-tier power transfer and data communication platform suitable for low-power, periodically-activated implantable analogue bio-sensors. In the inductive sub-system presented, 5 W of power is transferred across a 10 mm gap between a single pair of 39 mm (primary) and 33 mm (secondary) circular printed spiral coils (PSCs). These are printed using an 8000 dpi resolution photoplotter and fabricated on PCB by wet-etching, to the maximum permissible density. Our ultrasonic sub-system, consisting of a single pair of Pz21 (transmitter) and Pz26 (receiver) piezoelectric PZT ceramic discs driven by low-frequency, radial/planar excitation (-31 mode), without acoustic matching layers, is also reported here for the first time. The discs are characterised by propagation tank test and directly driven by the inductively coupled power to deliver 29 μW to a receiver (implant) employing a low voltage start-up IC positioned 70 mm deep within a homogeneous liquid phantom. No batteries are used. The deep implant is thus intermittently powered every 800 ms to charge a capacitor which enables its microcontroller, operating with a 500 kHz clock, to transmit a single nibble (4 bits) of digitized sensed data over a period of ~18 ms from deep within the phantom, to the outside world. A power transfer efficiency of 83% using our prototype CMOS logic-gate IC driver is reported for the inductively coupled part of the system. Overall prototype system power consumption is 2.3 W with a total power transfer efficiency of 1% achieved across the tiers

Aerospace Medicine and Biology: A continuing bibliography with indexes, supplement 142

This bibliography lists 256 reports, articles, and other documents introduced into the NASA scientific and technical information system in May 1975 for aerospace medicine and biology

Diagnostic and Therapeutic MEMS (Micro-Electro-Mechanical Systems) Devices for the Identification and Treatment of Human Disease

abstract: Early detection and treatment of disease is paramount for improving human health and wellness. Micro-scale devices promote new opportunities for the rapid, cost-effective, and accurate identification of altered biological states indicative of disease early-onset; these devices function at a scale more sensitive to numerous biological processes. The application of Micro-Electro-Mechanical Systems (MEMS) in biomedical settings has recently emerged and flourished over course of the last two decades, requiring a deep understanding of material biocompatibility, biosensing sensitively/selectively, biological constraints for artificial tissue/organ replacement, and the regulations in place to ensure device safety. Capitalizing on the inherent physical differences between cancerous and healthy cells, our ultra-thin silicone membrane enables earlier identification of bladder cancer—with a 70% recurrence rate. Building on this breakthrough, we have devised an array to multiplex this sample-analysis in real-time as well as expanding beyond bladder cancer. The introduction of new materials—with novel properties—to augment current and create innovative medical implants requires the careful analysis of material impact on cellular toxicity, mutagenicity, reactivity, and stability. Finally, the achievement of replacing defective biological systems with implanted artificial equivalents that must function within the same biological constraints, have consistent reliability, and ultimately show the promise of improving human health as demonstrated by our hydrogel check valve. The ongoing proliferation, expanding prevalence, and persistent improvement in MEMS devices through greater sensitivity, specificity, and integration with biological processes will undoubtedly bolster medical science with novel MEMS-based diagnostics and therapeutics.Dissertation/ThesisDoctoral Dissertation Electrical Engineering 201

DESIGN OPTIMIZATION AND PRECLINICAL TESTING OF PEDIATRIC ROTARY BLOOD PUMPS AND COMPONENTS: TOWARDS THE PEDIAFLOW® VAD

Limited options exist for children (BSA<1.5 m2) requiring long-term mechanical circulatory support (MCS). Unlike adults where compact, 3rd generation, continuous-flow, implantable rotary blood pumps (RBPs) are now the standard for ventricular assist device (VAD)-indications, the only pediatric-approved chronic MCS device is the Berlin Heart® EXCOR®: a 1st generation pulsatile, pneumatically-driven, paracorporeal life-saving technology albeit with a substantial risk profile associated with frequent neurological and coagulation-related serious adverse events. In support of the smallest and most vulnerable patients, the goal of this research is to facilitate the development and translation of next-generation pediatric RBPs, including the University of Pittsburgh-led Consortium’s PediaFlow®: a miniature, implantable, rotodynamic, fully magnetically levitated, continuous-flow pediatric VAD intended to support patients between 3 to 15 kg at a flow rates of 0.3-1.5 L/min for up to six months. Presented here is the i) development of a standardized method for in vitro mechanical blood trauma testing of pediatric MCS devices; ii) design and ex vivo evaluation of a novel, pediatric-appropriate, suction resistant, placement insensitive, left ventricular drainage cannula; iii) creation of an MCS-tailored monitoring software for preclinical testing; iv) development of a PediaFlow®-specific flow estimation algorithm; and v) hemocompatibility findings in vitro and in vivo of the 4th generation PediaFlow® (PF4) VAD. The PF4, comparable in size to an AA battery, is the embodiment of more than a decade of extensive computational and experimental efforts over the span of four device iterations to minimize size, optimize performance, and maximize safety. This dissertation represents the work and results to date of PediaFlow® PF4 on the path to preclinical testing to submit an Investigation Device Exception (IDE) application in anticipation of eventual clinical trials