keyword
MENU ▼
Read by QxMD icon Read
search

artificial retina

keyword
https://www.readbyqxmd.com/read/29775503/artificial-rod-and-cone-photoreceptors-with-human-like-spectral-sensitivities
#1
Byeongho Park, Heehong Yang, Tai Hwan Ha, Hyun Seo Park, Seung Ja Oh, Yong-Sang Ryu, Youngho Cho, Hyo-Suk Kim, Juyeong Oh, Dong Kyu Lee, Chulki Kim, Taikjin Lee, Minah Seo, Jaebin Choi, Young Min Jhon, Deok Ha Woo, Seok Lee, Seok Hwan Kim, Hyuk-Jae Lee, Seong Chan Jun, Hyun Seok Song, Tai Hyun Park, Jae Hun Kim
Photosensitive materials contain biologically engineered elements and are constructed using delicate techniques, with special attention devoted to efficiency, stability, and biocompatibility. However, to date, no photosensitive material has been developed to replace damaged visual-systems to detect light and transmit the signal to a neuron in the human body. In the current study, artificial nanovesicle-based photosensitive materials are observed to possess the characteristics of photoreceptors similar to the human eye...
May 18, 2018: Advanced Materials
https://www.readbyqxmd.com/read/29758028/a-surgical-simulator-for-peeling-the-inner-limiting-membrane-during-wet-conditions
#2
Seiji Omata, Yusei Someya, Shyn'ya Adachi, Taisuke Masuda, Takeshi Hayakawa, Kanako Harada, Mamoru Mitsuishi, Kiyohito Totsuka, Fumiyuki Araki, Muneyuki Takao, Makoto Aihara, Fumihito Arai
The present study was performed to establish a novel ocular surgery simulator for training in peeling of the inner limited membrane (ILM). This simulator included a next-generation artificial ILM with mechanical properties similar to the natural ILM that could be peeled underwater in the same manner as in actual surgery. An artificial eye consisting of a fundus and eyeball parts was fabricated. The artificial eye was installed in the eye surgery simulator. The fundus part was mounted in the eyeball, which consisted of an artificial sclera, retina, and ILM...
2018: PloS One
https://www.readbyqxmd.com/read/29752243/mechanical-stimulation-of-the-retina-therapeutic-feasibility-and-cellular-mechanism
#3
Corey M Rountree, Chen Meng, John B Troy, Laxman Saggere
Retinal prostheses that seek to restore vision by artificially stimulating retinal neurons with electrical current are an emerging treatment for photoreceptor degenerative diseases but face difficulties achieving naturalistic vision with high spatial resolution. Here, we report the unexpected discovery of a technique for mechanically stimulating retinal neurons with the potential to bypass the limitations of electrical stimulation. We found that pulsatile injections of standard Ames medium solution into explanted retinas of wild type rats under certain injection conditions (pulse-width > 50ms at 0...
May 2018: IEEE Transactions on Neural Systems and Rehabilitation Engineering
https://www.readbyqxmd.com/read/29691928/circadian-rhythms-refractive-development-and-myopia
#4
Ranjay Chakraborty, Lisa A Ostrin, Debora L Nickla, P Michael Iuvone, Machelle T Pardue, Richard A Stone
PURPOSE: Despite extensive research, mechanisms regulating postnatal eye growth and those responsible for ametropias are poorly understood. With the marked recent increases in myopia prevalence, robust and biologically-based clinical therapies to normalize refractive development in childhood are needed. Here, we review classic and contemporary literature about how circadian biology might provide clues to develop a framework to improve the understanding of myopia etiology, and possibly lead to rational approaches to ameliorate refractive errors developing in children...
May 2018: Ophthalmic & Physiological Optics: the Journal of the British College of Ophthalmic Opticians (Optometrists)
https://www.readbyqxmd.com/read/29691783/optimization-of-fixative-solution-for-retinal-morphology-a-comparison-with-davidson-s-fixative-and-other-fixation-solutions
#5
Kazuhiro Tokuda, Byron Baron, Yasuhiro Kuramitsu, Takao Kitagawa, Nobuko Tokuda, Naoyuki Morishige, Masaaki Kobayashi, Kazuhiro Kimura, Kazuyuki Nakamura, Koh-Hei Sonoda
PURPOSE: Numerous fixative solutions are available but many are not amenable to the histomorphological preservation of retinae. The investigators specifically focused on retinal histological studies, which rather than 4% formaldehyde (FA), often use Davidson's fixative. However the latter has its limitations. The purpose of this study was to produce a new fixative which maintains retinae closer to the in vivo conditions. STUDY DESIGN: Experimental design. METHODS: Four fixative formulations (4% paraformaldehyde, Davidson's fixative, modified Davidson's fixative and an in-house fixative - TB-Fix) were tested on retinae and the outcomes on histomorphology and immunohistochemical staining for selected antigenic markers was compared...
April 24, 2018: Japanese Journal of Ophthalmology
https://www.readbyqxmd.com/read/29669366/the-use-of-optical-coherence-tomography-for-the-detection-of-early-diabetic-retinopathy
#6
Gabor Mark Somfai, Heinrich Gerding, Delia Cabrera DeBuc
Diabetic retinopathy (DR) is one of the leading causes of vision loss globally with a severe burden on all societies due to its high treatment and rehabilitation costs. The early diagnosis of DR may provide preventive steps (including retinal laser therapy and tight carbohydrate, blood pressure, and cholesterol control) that could in turn help to avoid progression of the pathology with the resultant vision loss. Optical coherence tomography (OCT) enables the in vivo structural imaging of the retina, providing both qualitative (structure) and quantitative (thickness) information...
April 2018: Klinische Monatsblätter Für Augenheilkunde
https://www.readbyqxmd.com/read/29643781/two-cases-of-rhegmatogenous-retinal-detachment-associated-with-asteroid-hyalosis
#7
Yoshitaka Okuda, Keigo Kakurai, Takaki Sato, Seita Morishita, Masanori Fukumoto, Ryohsuke Kohmoto, Mai Takagi, Takatoshi Kobayashi, Teruyo Kida, Tsunehiko Ikeda
Background: To report two cases of rhegmatogenous retinal detachment (RRD) associated with asteroid hyalosis (AH). Case Presentation: Two patients presented with RRD originating from a flap tear. Case 1 involved a 62-year-old male who was found to have bullous RRD in his left eye originating from a flap tear. During vitreous surgery, a thick vitreous cortex was found to have strongly adhered to the entire retinal surface, from the center to the periphery. A bimanual method was then used in conjunction with the vitrectomy to create an artificial posterior vitreous detachment...
January 2018: Case Reports in Ophthalmology
https://www.readbyqxmd.com/read/29643775/case-report-of-a-family-affected-by-stickler-syndrome-in-which-rhegmatogenous-retinal-detachment-occurred-in-five-eyes-of-three-siblings
#8
Daisaku Kimura, Takaki Sato, Shou Oosuka, Ryohsuke Kohmoto, Masanori Fukumoto, Masashi Mimura, Kensuke Tajiri, Takatoshi Kobayashi, Teruyo Kida, Tsunehiko Ikeda
Purpose: Stickler syndrome is an autosomal dominant inherited disorder that is well known to be highly associated with the development of rhegmatogenous retinal detachment. In this study, we report the case of a family affected by Stickler syndrome in which rhegmatogenous retinal detachment developed in 5 eyes of 3 siblings. Case Series: For treatment, we performed vitreous surgery on 1 eye of the eldest son, and bilateral scleral buckling surgery on the 2 younger children...
January 2018: Case Reports in Ophthalmology
https://www.readbyqxmd.com/read/29624184/self-powered-vision-electronic-skin-basing-on-piezo-photodetecting-ppy-pvdf-pixel-patterned-matrix-for-mimicking-vision
#9
Wuxiao Han, Linlin Zhang, Haoxuan He, Hongmin Liu, Lili Xing, Xinyu Xue
The development of multifunctional electronic-skin that establishes human-machine interfaces, enhances perception abilities or has other distinct biomedical applications is the key to the realization of artificial intelligence. In this paper, a new self-powered (battery-free) flexible vision electronic-skin has been realized from pixel-patterned matrix of piezo-photodetecting PVDF/Ppy film. The electronic-skin under applied deformation can actively output piezoelectric voltage, and the outputting signal can be significantly influenced by UV illumination...
June 22, 2018: Nanotechnology
https://www.readbyqxmd.com/read/29587974/macular-photostress-and-visual-experience-between-microscope-and-intracameral-illumination-during-cataract-surgery
#10
Hyejin Seo, Dong Heun Nam, Jong Yeon Lee, Su Jin Park, Yu Jeong Kim, Seong-Woo Kim, Tae-Young Chung, Makoto Inoue, Terry Kim
PURPOSE: To evaluate macular photostress and visual experience between coaxial microscope illumination versus oblique intracameral illumination during cataract surgery. SETTING: Gachon University Gil Hospital, Incheon, South Korea. DESIGN: Prospective case series. METHODS: Consecutive patients who had cataract surgery using microscope illumination and intracameral illumination were included. The patients were asked to complete a questionnaire (seeing strong lights, feeling photophobia, feeling startled (fright) when seeing lights, seeing any colors, seeing any instruments or surgical procedures, and estimating intraoperative visual function) designed to describe their cataract surgery experience...
February 2018: Journal of Cataract and Refractive Surgery
https://www.readbyqxmd.com/read/29543853/removal-of-the-blue-component-of-light-significantly-decreases-retinal-damage-after-high-intensity-exposure
#11
Javier Vicente-Tejedor, Miguel Marchena, Laura Ramírez, Diego García-Ayuso, Violeta Gómez-Vicente, Celia Sánchez-Ramos, Pedro de la Villa, Francisco Germain
Light causes damage to the retina (phototoxicity) and decreases photoreceptor responses to light. The most harmful component of visible light is the blue wavelength (400-500 nm). Different filters have been tested, but so far all of them allow passing a lot of this wavelength (70%). The aim of this work has been to prove that a filter that removes 94% of the blue component may protect the function and morphology of the retina significantly. Three experimental groups were designed. The first group was unexposed to light, the second one was exposed and the third one was exposed and protected by a blue-blocking filter...
2018: PloS One
https://www.readbyqxmd.com/read/29515386/low-latency-line-tracking-using-event-based-dynamic-vision-sensors
#12
Lukas Everding, Jörg Conradt
In order to safely navigate and orient in their local surroundings autonomous systems need to rapidly extract and persistently track visual features from the environment. While there are many algorithms tackling those tasks for traditional frame-based cameras, these have to deal with the fact that conventional cameras sample their environment with a fixed frequency. Most prominently, the same features have to be found in consecutive frames and corresponding features then need to be matched using elaborate techniques as any information between the two frames is lost...
2018: Frontiers in Neurorobotics
https://www.readbyqxmd.com/read/29511183/nanowire-arrays-restore-vision-in-blind-mice
#13
Jing Tang, Nan Qin, Yan Chong, Yupu Diao, Yiliguma, Zhexuan Wang, Tian Xue, Min Jiang, Jiayi Zhang, Gengfeng Zheng
The restoration of light response with complex spatiotemporal features in retinal degenerative diseases towards retinal prosthesis has proven to be a considerable challenge over the past decades. Herein, inspired by the structure and function of photoreceptors in retinas, we develop artificial photoreceptors based on gold nanoparticle-decorated titania nanowire arrays, for restoration of visual responses in the blind mice with degenerated photoreceptors. Green, blue and near UV light responses in the retinal ganglion cells (RGCs) are restored with a spatial resolution better than 100 µm...
March 6, 2018: Nature Communications
https://www.readbyqxmd.com/read/29445713/effects-of-laser-physical-parameters-on-lesion-size-in-retinal-photocoagulation-surgery-clinical-oct-and-experimental-study
#14
A Soleimani, S H Rasta, T Banaei, A Asgharsharghi Bonab
Introduction: The aim of the present study was to determine burn intensity in retinal laser photocoagulation based on laser parameters; wavelength, power, beam size and pulse duration, using Optical Coherence Tomography (OCT), fundus camera, physical eye model and computer simulation in a clinical study. Materials and Methods: Participants were 10 adult patients between 50-80 years with proliferative diabetic retinopathy. A multicolor-photo coagulator with 532 nm green and 672 nm red for retina photocoagulation in diabetic retinopathy was used to investigate the participants...
December 2017: Journal of Biomedical Physics & Engineering
https://www.readbyqxmd.com/read/29445326/structure-function-studies-of-the-%C3%AE-4-subunit-reveal-evolutionary-loss-of-a-glyr-subtype-involved-in-startle-and-escape-responses
#15
Sophie Leacock, Parnayan Syed, Victoria M James, Anna Bode, Koichi Kawakami, Angelo Keramidas, Maximiliano Suster, Joseph W Lynch, Robert J Harvey
Inhibitory glycine receptors (GlyRs) are pentameric ligand-gated anion channels with major roles in startle disease/hyperekplexia (GlyR α1), cortical neuronal migration/autism spectrum disorder (GlyR α2), and inflammatory pain sensitization/rhythmic breathing (GlyR α3). However, the role of the GlyR α4 subunit has remained enigmatic, because the corresponding human gene ( GLRA4 ) is thought to be a pseudogene due to an in-frame stop codon at position 390 within the fourth membrane-spanning domain (M4). Despite this, a recent genetic study has implicated GLRA4 in intellectual disability, behavioral problems and craniofacial anomalies...
2018: Frontiers in Molecular Neuroscience
https://www.readbyqxmd.com/read/29415876/electric-stimulus-duration-alters-network-mediated-responses-depending-on-retinal-ganglion-cell-type
#16
Maesoon Im, Paul Werginz, Shelley I Fried
OBJECTIVE: To improve the quality of artificial vision that arises from retinal prostheses, it is important to bring electrically-elicited neural activity more in line with the physiological signaling patterns that arise normally in the healthy retina. Our previous study reported that indirect activation produces a closer match to physiological responses in ON retinal ganglion cells (RGCs) than in OFF cells (Im and Fried 2015 J. Physiol. 593 3677-96). This suggests that a preferential activation of ON RGCs would shape the overall retinal response closer to natural signaling...
June 2018: Journal of Neural Engineering
https://www.readbyqxmd.com/read/29286422/methodology-for-biomimetic-chemical-neuromodulation-of-rat-retinas-with-the-neurotransmitter-glutamate-in-vitro
#17
Corey M Rountree, John B Troy, Laxman Saggere
Photoreceptor degenerative diseases cause irreparable blindness through the progressive loss of photoreceptor cells in the retina. Retinal prostheses are an emerging treatment for photoreceptor degenerative diseases that seek to restore vision by artificially stimulating the surviving retinal neurons in the hope of eliciting comprehensible visual perception in patients. Current retinal prostheses have demonstrated success in restoring limited vision to patients using an array of electrodes to electrically stimulate the retina but face substantial physical barriers in restoring high acuity, natural vision to patients...
December 19, 2017: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/29196319/object-representations-in-human-visual-cortex-formed-through-temporal-integration-of-dynamic-partial-shape-views
#18
Tanya Orlov, Ehud Zohary
We typically recognize visual objects using the spatial layout of their parts, which are present simultaneously on the retina. Therefore, shape extraction is based on integration of the relevant retinal information over space. The lateral occipital complex (LOC) can represent shape faithfully in such conditions. However, integration over time is sometimes required to determine object shape. To study shape extraction through temporal integration of successive partial shape views, we presented human participants (both men and women) with artificial shapes that moved behind a narrow vertical or horizontal slit...
January 17, 2018: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/29140328/retina-simulating-phantom-produced-by-photolithography
#19
Denise Valente, Brian Vohnsen
Cone photoreceptors have a narrow acceptance angle that is well matched to the size of the eye pupil and dampens the visual impact of aberrations and scattering. However, the structure of the human retina is not replicated in existing eye models used to test refractive designs or retinal implants that restore partial vision to the blind. Here, we report on an artificial waveguide-based retinal phantom manufactured by photolithography in photoresist film with dimensions and refractive index contrast similar to the retinal receptor layer...
November 15, 2017: Optics Letters
https://www.readbyqxmd.com/read/29127485/oct-based-deep-learning-algorithm-for-the-evaluation-of-treatment-indication-with-anti-vascular-endothelial-growth-factor-medications
#20
Philipp Prahs, Viola Radeck, Christian Mayer, Yordan Cvetkov, Nadezhda Cvetkova, Horst Helbig, David Märker
PURPOSE: Intravitreal injections with anti-vascular endothelial growth factor (anti-VEGF) medications have become the standard of care for their respective indications. Optical coherence tomography (OCT) scans of the central retina provide detailed anatomical data and are widely used by clinicians in the decision-making process of anti-VEGF indication. In recent years, significant progress has been made in artificial intelligence and computer vision research. We trained a deep convolutional artificial neural network to predict treatment indication based on central retinal OCT scans without human intervention...
January 2018: Graefe's Archive for Clinical and Experimental Ophthalmology
keyword
keyword
28465
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"