Fabrication and validation of flexible neural electrodes based on polyimide tape and gold sheet.

This research was conducted to apply polyimide tape, which has the advantages of low price ans strong adhesive strength, to the neural electrode process. In addition, to maximize the low-cost characteristics, a fabrication process based on UV laser patterning rather than a photolithography process was introduced. The fabrication process started by attaching the gold sheet on the conductive double-sided tape without being torn or crushed.

Low dead space encapsulation and integration of circuits for retinal prosthesis based on cyclic olefin copolymer.

A retinal prosthesis is a device that can provide artificial vision to people who have lost their sight from certain retinal disorder. Because the device needs to be inserted into the body, high flexibility and reliability is required. Recently, devices using thermoplastic polymers such as LCP and COC as substrates have been studied.

Fabrication of Implantable Microelectrode Array using Cyclic Olefin Copolymer and SU-8 via Photocrosslinking Lamination.

In this work, a fabrication process for implantable electrodes using a Cyclic Olefin Copolymer (COC) substrate and a SU-8 passivation layer was presented. COC and SU-8 were shown to be suitable for implantable neural electrodes due to their biocompatibility, chemical resistance, and thermal stability. The electrodes were successfully patterned on the COC film, and the SU-8 passivation layer was coated while maintaining site-opened via photolithography.

Feasibility, credence, and usefulness of out-of-office cuffless blood pressure monitoring using smartwatch: a population survey.

Background: Cuffless blood pressure (BP) measurement, enabled by recent advances in wearable devices, allows for BP monitoring in daily life. This study aims to evaluate the feasibility, cresdence, and usefulness of cuffless BP monitoring through a population survey.

Methods: During the "Daily BP Measurement with Your Galaxy Watch" campaign held by the Korean Society of Hypertension, participants were asked to share their experiences with cuffless BP measurement using a smartwatch application through an online survey.

Automatic Lung Cancer Segmentation in [F]FDG PET/CT Using a Two-Stage Deep Learning Approach.

Purpose: Since accurate lung cancer segmentation is required to determine the functional volume of a tumor in [F]FDG PET/CT, we propose a two-stage U-Net architecture to enhance the performance of lung cancer segmentation using [F]FDG PET/CT.

Methods: The whole-body [F]FDG PET/CT scan data of 887 patients with lung cancer were retrospectively used for network training and evaluation. The ground-truth tumor volume of interest was drawn using the LifeX software.

Feasibility and measurement stability of smartwatch-based cuffless blood pressure monitoring: A real-world prospective observational study.

Cuffless wearable devices are currently being developed for long-term monitoring of blood pressure (BP) in patients with hypertension and in apparently healthy people. This study evaluated the feasibility and measurement stability of smartwatch-based cuffless BP monitoring in real-world conditions. Users of the first smartwatch-based cuffless BP monitor approved in Korea (Samsung Galaxy Watch) were invited to upload their data from using the device for 4 weeks post calibration.

Neurostimulators for high-resolution artificial retina: ASIC design challenges and solutions.

Neurostimulator is one of the most important part in artificial retina design. In this paper, we discuss the main challenges in the design of application-specific integrated circuit for high-resolution artificial retina and suggest corresponding solutions..

Subcutaneously implantable electromagnetic biosensor system for continuous glucose monitoring.

Continuous glucose monitoring systems (CGMS) are becoming increasingly popular in diabetes management compared to conventional methods of self-blood glucose monitoring systems. They help understanding physiological responses towards nutrition intake, physical activities in everyday life and glucose control. CGMS available in market are of two types based on their working principle.

Minimally Invasive Implant Type Electromagnetic Biosensor for Continuous Glucose Monitoring System: In Vivo Evaluation.

Objective: Continuous glucose monitoring system (CGMS) is growing popular and preferred by diabetes over conventional methods of self-blood glucose monitoring (SBGM) systems. However, currently available commercial CGMS in the market is useful for few days to few months. This paper presents a durable, highly sensitive and minimally invasive implant type electromagnetic sensor for continuous glucose monitoring that is capable of tracking minute changes in blood glucose level (BGL).

Investigation of neural electrode fabrication process on Polycarbonate substrate.

Polycarbonate is a polymer that has been widely used including medical application due to its useful properties. It has high temperature resistance, biocompatibility, transparency and low water absorption rate, which are needful characteristics for packaging material of implantable neural prosthetic devices. In this study, we investigated fabrication of neural electrode with polycarbonate film using standard photolithography process and heated hydraulic press for thermal lamination.

Selective Edge Rounding of Cyclic Olefin Copolymer Film Using UV Laser for Implantable Electrode Package.

Cyclic Olefin Copolymer is emerging as a packaging material for implantable electrodes due to its physical properties such as low water absorption rate and low water vapor permeability. The electrode-tissue interface is often regarded as a major focus of implantable electrodes, but its packaging should also be considered thoroughly since it directly contacts the adjoining body cells. Therefore, eliminating any sharp boundaries or edges around the package would be beneficial to minimize potential inflammatory responses caused by physical/mechanical stresses.

Manually wound coil fabrication process based on cyclic olefin copolymer substrate.

Neural prostheses are systems that interact with the human nervous system to recover function lost as a result of disease by recording or stimulating neural signals. Neural implants have a variety of components, but among them, designing highly efficient wireless power transmission systems is particularly important. However, there is a problem that it is difficult to design a wireless power transmission system with high transmission efficiency because power transmission efficiency is affected by various coil parameters.

The Design and Analysing Heating Effect of Spiral Planar Coil in COMSOL Multiphysics for Implantable Artificial Retina.

In this paper, simulation data and heat generation due to electromagnetic from spiral planar pair of coils for arti-ficial retinal implant were analyzed by COMSOL Multiphysics. Planar spiral outer and inner coils for an implantable artificial retina were designed and analyzed. The whole geometry was designed in a transplant situation.

Low-cost, thermoplastic micro-lens array with a carbon black light screen for bio-mimetic vision.

Micro-lens array is a great example of bio-mimetic technology which was inspired by compound eyes found in insects and is used in lasers, optical communication, and 3D imaging. In this study, a micro-lens array was fabricated from cyclic olefin copolymer using a cost-effective method: compression molding and thermal reflow. Also, a light screen was installed between lenses to reduce the optical interference for clearer individual images.

Vision-correcting holographic display: evaluation of aberration correcting hologram.

Vision-correcting displays are key to achieving physical and physiological comforts to the users with refractive errors. Among such displays are holographic displays, which can provide a high-resolution vision-adaptive solution with complex wavefront modulation. However, none of the existing hologram rendering techniques have considered the optical properties of the human eye nor evaluated the significance of vision correction.

Artificial Compound Eye Systems and Their Application: A Review.

The natural compound eye system has many outstanding properties, such as a more compact size, wider-angle view, better capacity to detect moving objects, and higher sensitivity to light intensity, compared to that of a single-aperture vision system. Thanks to the development of micro- and nano-fabrication techniques, many artificial compound eye imaging systems have been studied and fabricated to inherit fascinating optical features of the natural compound eye. This paper provides a review of artificial compound eye imaging systems.

Current Stimulation of the Midbrain Nucleus in Pigeons for Avian Flight Control.

A number of research attempts to understand and modulate sensory and motor skills that are beyond the capability of humans have been underway. They have mainly been expounded in rodent models, where numerous reports of controlling movement to reach target locations by brain stimulation have been achieved. However, in the case of birds, although basic research on movement control has been conducted, the brain nuclei that are triggering these movements have yet to be established.

Change in the eye position under general anesthesia in children with intermittent exotropia.

Purpose: To evaluate the eye position in subjects with intermittent exotropia and normal subjects under general anesthesia (GA) using the strabismus photo analyzer.

Methods: This retrospective case-control study included 78 subjects with intermittent exotropia and 25 normal control subjects who underwent epiblepharon surgery. Eye position under GA was assessed using the strabismus photo analyzer, based on eye models generated from corneal lights and limbus in pre- and post-anesthesia images.

Effect of Ultra-high-definition Television on Ocular Surface and Fatigue.

Purpose: To investigate the effects of watching ultra-high-definition television (UHD TV) on subjective ocular fatigue and objective ocular surface indices.

Methods: A total of 76 volunteers were recruited for this study. Subjects watched UHD TV for 10 minutes at a viewing distance of 110 cm.

Light-Induced Fluorescence-Based Device and Hybrid Mobile App for Oral Hygiene Management at Home: Development and Usability Study.

Background: Dental diseases can be prevented through the management of dental plaques. Dental plaque can be identified using the light-induced fluorescence (LIF) technique that emits light at 405 nm. The LIF technique is more convenient than the commercial technique using a disclosing agent, but the result may vary for each individual as it still requires visual identification.

Investigation of stereotactic surgery for avian brain stimulation by a fully implanted wireless system.

Objective: The authors' goal was to study avian motor brain mapping via wireless stimulation to induce certain behaviors. In this paper, the authors propose an electrode design that is suitable for avian brain stimulation as well as a stereotactic implant procedure for the proposed electrode.

Methods: An appropriate breed for avian brain study was chosen.

New Strategy of Visual Acuity Assessment by Consecutively-sized Landolt Ring Symbol.

In this paper, novel visual acuity test strategy is proposed. Unlike conventional way, an instructor shows a subject the magnifying image of Landolt ring through the monitor. By adapting multiple reliability verification system using feedback, instructor can get the vision acuity data with higher accuracy and resolution.

A Fully Implantable Wireless Stimulation System for Pigeon Navigation.

Navigation of freely moving animals has been studied for potential application to emergency situations and hazardous environments. A fully implantable stimulation system for remote animal navigation was proposed and applied to living pigeons. The animal navigation system, consisting of an external controller and a neural stimulator, was designed based on the anatomy of the pigeons.