Download or read book A Curvable Silicon Retinal Implant written by Rostam Dinyari and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In age-related macular degeneration (AMD) and retinitis pigmentosa (RP), two leading causes of blindness, the photoreceptor layer of the retina is degenerated while the rest of the retina is well preserved. The function of the photoreceptors is very similar to that of solar cells. Upon receiving light, they activate the inner layers of the retina by producing electrical and chemical signals. These signals are then processed and compressed by a complex circuit of retinal neurons (horizontal cells, bipolar cells, amacrine cells, and ganglion cells) and sent to the brain. The brain perceives these data as sight. Electronic retinal implant systems seek to restore sight in AMD and RP by electrical stimulation of the surviving retinal neurons. Currently the more dominant systems consist of a microelectrode array, which is placed directly on the ganglion cells (epiretinal). In this approach, a camera mounted on goggles captures video which is then processed by a pocket computer. The power and data are then transmitted wirelessly to an extraocular receiver unit. Through an intraocular cable, the receiver unit sends appropriate electrical stimuli to the array of microelectrodes. The electrodes then stimulate the ganglion cells by passing current pulses through the tissue. These stimulations are perceived by the brain as spots of light. The epiretinal approach has some disadvantages. Because the electrodes directly stimulate the ganglion cells, the image processing and data compression capabilities of the retina are not utilized. Placing the extraocular receiver unit and connecting it via a cable to the microelectrode array significantly complicates the surgical procedure and increases the chance of post surgical complications. Additionally, the perceived images are independent of the eye movements. We have developed an integrated photovoltaic monolithic silicon retinal implant that requires no electrical power or data connection. In our design, a miniature camera captures video that is processed by a pocket computer before being projected into the eye at a near-infrared wavelength ([Lambda] = 905 nm) onto the silicon implant located in the subretinal space (area in the back of the retina). The implant consists of a two-dimensional array of photovoltaic pixels. The projected image is provided in pulsed fashion and each pixel element consists of up to three series-connected photovoltaic cells such that the pixels deliver current pulses that are sufficiently strong to stimulate the remaining functional neural cells. The current pulses are interpreted as visual images by the brain. Placing the implant in the subretinal space allows for utilization of the existing image processing and data compression functions of the retina. Each pixel receives both power and data directly through laser radiation. This eliminates the need for a separate wireless receiver unit and simplifies the surgical procedures and reduces the post-surgical risks. Additionally, in this approach, eye movements change the perceived images. The novelty of the work reported here is the integration of photovoltaic devices in a MEMS process that allows the implant to deform to the natural curvature of the eye, while also providing isolation between the bodies of the three series-connected subpixels that make up each pixel. This was achieved by patterning the implants into an array of pixels connected together by deformable silicon flexures. In addition, the trenches also provide electrical isolation between the three series-connected photovoltaic subpixels. Curving the implant is advantageous since the complete implant is in focus, resulting in optimum quality of vision perceived. Curved implants can also be substantially larger than planar implants and can hence cover a larger part of the field of view. A curvable implant also causes no mechanical strain or abnormality in the eye. Usage of three series-connected subpixels per pixel improves the impedance matching to the surrounding tissue and enhances the injected current per pixel allowing for higher resolution implants. Fabricated implant with a resolution of 64 pixels/mm2 can inject sufficient current for neural activation at safe optical intensities. Additionally, the exchange of nutrients and waste, which is necessary for the survival of the retinal cells, is provided by diffusion through the trenches that define the silicon devices.
Download or read book Flexible and Curved Focal Plane Arrays for Image Sensing Applications written by and published by Parilee Edison. This book was released on with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Foldable Flex and Thinned Silicon Multichip Packaging Technology written by John W. Balde and published by Springer Science & Business Media. This book was released on 2013-11-27 with total page 357 pages. Available in PDF, EPUB and Kindle. Book excerpt: Foldable Flex and Thinned Silicon Multichip Packaging Technology presents newly emerging methods used to make stacked chip packages in the so-called 2-1/2 D technology (3-D in physical format, but interconnected only through the circuits on folded flex). It is also being used in single chip packages where the thinness of the chips and the flex substrate made packages significantly thinner than through any other means.
Download or read book Ultra thin Chip Technology and Applications written by Joachim Burghartz and published by Springer Science & Business Media. This book was released on 2010-11-18 with total page 471 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ultra-thin chips are the "smart skin" of a conventional silicon chip. This book shows how very thin and flexible chips can be fabricated and used in many new applications in microelectronics, Microsystems, biomedical and other fields. It provides a comprehensive reference to the fabrication technology, post processing, characterization and the applications of ultra-thin chips.
Download or read book Visual Prosthesis and Ophthalmic Devices written by Joyce Tombran-Tink and published by Springer Science & Business Media. This book was released on 2007-12-08 with total page 277 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume details the latest technology in treating eye injuries and infections. It provides insight into the most up-to-date and established treatment options. The volume focuses on what can currently be achieved with a variety of ocular prostheses as well as what the future holds. Coverage reviews issues such as intraocular lens implants, biocompatibility of materials, retinal implants, testing models, and software designs.
Download or read book Silicone Implants written by Jacqueline Van de Kamp and published by . This book was released on 1994 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Silicone Implants written by Jennie P. Hunt and published by . This book was released on 1992 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A review flexible devices for nerve stimulation written by Ze-Qing Liu and published by OAE Publishing Inc.. This book was released on 2024-01-10 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nerve stimulation technology utilizing electricity, magnetism, light, and ultrasound has found extensive applications in biotechnology and medical fields. Neurostimulation devices serve as the crucial interface between biological tissue and the external environment, posing a bottleneck in the advancement of neurostimulation technology. Ensuring safety and stability is essential for their future applications. Traditional rigid devices often elicit significant immune responses due to the mechanical mismatch between their materials and biological tissues. Consequently, there is a growing demand for flexible nerve stimulation devices that offer enhanced treatment efficacy while minimizing irritation to the human body. This review provides a comprehensive summary of the historical development and recent advancements in flexible devices utilizing four neurostimulation techniques: electrical stimulation, magnetic stimulation, optic stimulation, and ultrasonic stimulation. It highlights their potential for high biocompatibility, low power consumption, wireless operation, and superior stability. The aim is to offer valuable insights and guidance for the future development and application of flexible neurostimulation devices.
Download or read book Implantable Neural Prostheses 1 written by David Zhou and published by Springer Science & Business Media. This book was released on 2009-06-10 with total page 391 pages. Available in PDF, EPUB and Kindle. Book excerpt: Significant progress has been made in the development of neural prostheses to restore human functions and improve the quality of human life. Biomedical engineers and neuroscientists around the world are working to improve design and performance of existing devices and to develop novel devices for artificial vision, artificial limbs, and brain–machine interfaces. This book, Implantable Neural Prostheses 1: Devices and Applications,ispart one of a two-book series and describes state-of-the-art advances in techniques associated with implantable neural prosthetic devices and their applications. Devices covered include sensory prosthetic devices, such as visual implants, cochlear implants, auditory midbrain implants, and spinal cord stimulators. Motor prosthetic devices, such as deep brain stimulators, Bion microstimu- tors, the brain control and sensing interface, and cardiac electro-stimulation devices are also included. Progress in magnetic stimulation that may offer a non-invasive approach to prosthetic devices is introduced. Regulatory approval of implantable medical devices in the United States and Europe is also discussed.
Download or read book Implantable Microdevices written by Wen Li and published by MDPI. This book was released on 2019-10-23 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt: Implantable microdevices, providing accurate measurement of target analytes in animals and humans, have always been important in biological science, medical diagnostics, clinical therapy, and personal healthcare. Recently, there have been increasing unmet needs for developing high-performance implants that are small, minimally-invasive, biocompatible, long-term stable, and cost-effective. Therefore, the aim of this Special Issue is to bring together state-of-the-art research and development contributions that address key challenges and topics related to implantable microdevices. Applications of primary interest include, but are not limited to, miniaturized optical sensing and imaging tools, implantable sensors for detecting biochemical species and/or metabolites, transducers for measuring biophysical quantities (e.g., pressure and/or strain), and neural prosthetic devices.
Download or read book Neural Engineering written by Bin He and published by Springer Nature. This book was released on 2020-09-21 with total page 707 pages. Available in PDF, EPUB and Kindle. Book excerpt: This third edition overviews the essential contemporary topics of neuroengineering, from basic principles to the state-of-the-art, and is written by leading scholars in the field. The book covers neural bioelectrical measurements and sensors, EEG signal processing, brain-computer interfaces, implantable and transcranial neuromodulation, peripheral neural interfacing, neuroimaging, neural modelling, neural circuits and system identification, retinal bioengineering and prosthetics, and neural tissue engineering. Each chapter is followed by homework questions intended for classroom use. This is an ideal textbook for students at the graduate and advanced undergraduate level as well as academics, biomedical engineers, neuroscientists, neurophysiologists, and industry professionals seeking to learn the latest developments in this emerging field. Advance Praise for Neural Engineering, 3rd Edition: “A comprehensive and timely contribution to the ever growing field of neural engineering. Bin He’s edited volume provides chapters that cover both the fundamentals and state-of-the-art developments by the world’s leading neural engineers." Dr. Paul Sajda, Department of Biomedical Engineering, Electrical Engineering and Radiology, Columbia University “Neural Engineering, edited by Prof. He, is an outstanding book for students entering into this fast evolving field as well as experienced researchers. Its didactic and comprehensive style, with each chapter authored by leading scientific authorities, provides the ultimate reference for the field.” Dr. Dario Farina, Department of Bioengineering, Imperial College London, London, UK "Neural Engineering has come of age. Major advances have made possible prosthesis for the blind, mind control for quadraplegics and direct intervention to control seizures in epilepsy patients. Neural Engineering brings together reviews by leading researchers in this flourishing field. Dr. Terrence Sejnowski, Salk Institute for Biolgical Studies and UC San Diego
Download or read book Retina written by David R. Hinton and published by Elsevier Health Sciences. This book was released on 2005-09-21 with total page 2744 pages. Available in PDF, EPUB and Kindle. Book excerpt: Praised by JAMA as "The most complete description of the development, structure, function, pathophysiology, and treatment of the retina and its diseases to be found anywhere," this monumental three-volume work puts all of today's scientific and clinical knowledge of the retina at readers' fingertips. The New Edition has been comprehensively updated and reorganized to reflect all of the very latest scientific and genetic discoveries, diagnostic imaging methods, drug therapies, treatment recommendations, and surgical techniques. The result is an indispensable reference and diagnostic tool for generalists and specialists alike. Delivers the editorial expertise of four highly respected authorities, as well as contributions from internationally recognized leaders in visual science, ophthalmology, and vitreoretinal studies. Presents more than 3,400 superb illustrations (2,200 in full color) that capture all forms of retinal disease from every perspective. Offers the very latest information on the genetic basis of retinal disease, diagnostic retinal imaging, photodynamic therapy, and age-related macular degeneration. Examines the most recent advances in diagnostic indocyanine green angiography � optical coherence tomography (OCT) and quantitative fluoroscein angiography � macular translocation with 360� peripheral retinectomy � surgery for diffuse macular edema due to multiple causes, including proliferative vitreoretinopathy � artificial vision � and much more. Features a completely restructured section on age-related macular degeneration that includes epidemiology and risk factors � prophylaxis and prevention knowledge gained from large clinical trials like AREDS � proven and experimental treatments for AMD � and pharmacotherapy. Incorporates a multitude of new full-color images, 2200 in all.
Download or read book Bioelectronic Vision Retina Models Evaluation Metrics And System Design written by Joao Carlos Martins and published by World Scientific. This book was released on 2009-01-05 with total page 271 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a sound mathematical and technical perspective in functional and structural retina models, presents evaluation metrics to assess those models, and provides insights about the models hardware implementation.It begins by introducing the retina anatomy and its workings in a detailed way suitable for an engineering audience, while providing the mathematical analysis of the retina neural response. Moreover, it explores and establishes a framework for the comparison of retina models by organizing a set of metrics for testing and evaluating the different models.The book follows a signal processing perspective, where all models and metrics are discretized in order to be implemented and tested in a digital system, such as a computer or a specialized dedicated hardware device.
Download or read book World Congress on Medical Physics and Biomedical Engineering September 7 12 2009 Munich Germany written by Olaf Dössel and published by Springer Science & Business Media. This book was released on 2010-01-04 with total page 619 pages. Available in PDF, EPUB and Kindle. Book excerpt: Present Your Research to the World! The World Congress 2009 on Medical Physics and Biomedical Engineering – the triennial scientific meeting of the IUPESM - is the world’s leading forum for presenting the results of current scientific work in health-related physics and technologies to an international audience. With more than 2,800 presentations it will be the biggest conference in the fields of Medical Physics and Biomedical Engineering in 2009! Medical physics, biomedical engineering and bioengineering have been driving forces of innovation and progress in medicine and healthcare over the past two decades. As new key technologies arise with significant potential to open new options in diagnostics and therapeutics, it is a multidisciplinary task to evaluate their benefit for medicine and healthcare with respect to the quality of performance and therapeutic output. Covering key aspects such as information and communication technologies, micro- and nanosystems, optics and biotechnology, the congress will serve as an inter- and multidisciplinary platform that brings together people from basic research, R&D, industry and medical application to discuss these issues. As a major event for science, medicine and technology the congress provides a comprehensive overview and in–depth, first-hand information on new developments, advanced technologies and current and future applications. With this Final Program we would like to give you an overview of the dimension of the congress and invite you to join us in Munich! Olaf Dössel Congress President Wolfgang C.
Download or read book Green Materials for Electronics written by Mihai Irimia-Vladu and published by John Wiley & Sons. This book was released on 2017-09-04 with total page 446 pages. Available in PDF, EPUB and Kindle. Book excerpt: Combining the materials science, technological, and device aspects of organic bioelectronics based on green materials, this is the first overview of the emerging concepts involving fabrication techniques for sustainable electronics with low energy and material consumption. With contributions from top-notch editors and authors, in one focus, the book covers a collection of natural materials suited for electronics applications such as paper, silk, melanin, DNA and nucleobases, resins, gums, saccharides, cellulose, gelatine and peptides. In another thrust, the book focuses on device fabrication based on these materials, including processing aspects, and applications such as sensors, signal transducers, transient, implantable and digestible electronics. With its interdisciplinary approach this text will appeal to the chemistry, physics, materials science, and engineering communities.
Download or read book Implantable Sensor Systems for Medical Applications written by Andreas Inmann and published by Elsevier. This book was released on 2013-01-02 with total page 535 pages. Available in PDF, EPUB and Kindle. Book excerpt: Implantable sensor systems offer great potential for enhanced medical care and improved quality of life, consequently leading to major investment in this exciting field. Implantable sensor systems for medical applications provides a wide-ranging overview of the core technologies, key challenges and main issues related to the development and use of these devices in a diverse range of medical applications.Part one reviews the fundamentals of implantable systems, including materials and material-tissue interfaces, packaging and coatings, microassembly, electrode array design and fabrication, and the use of biofuel cells as sustainable power sources. Part two goes on to consider the challenges associated with implantable systems. Biocompatibility, sterilization considerations and the development of active implantable medical devices in a regulated environment are discussed, along with issues regarding data protection and patient privacy in medical sensor networks. Applications of implantable systems are then discussed in part three, beginning with Microelectromechanical systems (MEMS) for in-vivo applications before further exploration of tripolar interfaces for neural recording, sensors for motor neuroprostheses, implantable wireless body area networks and retina implants.With its distinguished editors and international team of expert contributors, Implantable sensor systems for medical applications is a comprehensive guide for all those involved in the design, development and application of these life-changing technologies. Provides a wide-ranging overview of the core technologies, key challenges and main issues related to the development and use of implantable sensor systems in a range of medical applications Reviews the fundamentals of implantable systems, including materials and material-tissue interfaces, packaging and coatings, and microassembly Considers the challenges associated with implantable systems, including biocompatibility and sterilization
Download or read book Visual Prosthesis written by Jeffrey N. Weiss and published by Springer Nature. This book was released on 2022-08-22 with total page 125 pages. Available in PDF, EPUB and Kindle. Book excerpt: For the millions of people with untreatable blindness the thought of a visual prosthesis that would allow them to live a normal life has always been a distant hope. There have been intermittent bright spots that periodically fan that hope such as when Dr. Dobelle’s visual prosthesis patient drove a car in an empty parking lot. This book will serve as an update of the work in developing a visual prosthesis. Chapters discuss the physiologic and engineering issues, alternative strategies, and patents, as well as recent research studies. Visual Prosthesis - A Concise Guide is a must-have resource for ophthalmologists, neurologists, engineers and physicists.
