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The first deaf-blind patient in Russia with Argus II retinal prosthesis system. What he sees and why
摘要： A 59-year-old man with retinitis pigmentosa and hearing loss (clinical Usher syndrome) underwent surgery to implant the Argus II retinal prosthesis system in the right eye. This is the first case of retinal implant surgery in the Russian Federation. In this study we propose a new method for evaluating the functional results after implantation of the Argus II, the statistical analysis was performed to find correlations between the sizes of phosphenes that the patient drew and then were digitalized, and the height of the subimplant interface, retinal thickness, impedance, and perceptual threshold, which showed interesting mixed results. Correlation analysis showed the weak dependency between the size of a phosphene and the perceptual threshold and we did not find significant correlations between a phosphene and the height of the interface, impedance and retinal thickness.
关键词： Argus II,Usher syndrome,retinitis pigmentosa,deaf-blind,blind,artificial vision,retinal prosthesis system,retinal implant,deafblind
更新于2025-09-23 15:23:52
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In vitro reliability testing and in vivo lifespan estimation of wireless Pixium Vision PRIMA photovoltaic subretinal prostheses suggest prolonged durability and functionality in clinical practice
摘要： Objective. Retinal implants have the potential to restore some sight in patients with retinal degeneration. The PRIMA implant’s novel design features simpler insertion and no transscleral cabling or extraocular components. This in vitro study investigated PRIMA’s durability under real time and accelerated conditions and estimated the device’s lifespan in vivo. Approach. Two potential failure modes were examined: corrosion and overstimulation. Real-time aging was tested using implants immersed in balanced saline solution (BSS) at 37°C, mimicking the intraocular environment. Accelerated aging was examined at 77°C (Arrhenius theory). Confirmatory testing of acceleration factor was performed using different temperatures (37°C-87°C) and weakened implant coatings. The effect of repeated maximum stimulation was tested using a pulsed infrared laser (6x acceleration factor). Data were used to estimate device lifespan. Main results. 175 implants were tested for up to 33 months. No corrosion or water ingress was observed after approximately 20 accelerated years. A pixel failure rate of 0.15% was recorded after 10 accelerated years’ stimulation. The derived lifespan estimation for the PRIMA implant was 27.0 years with a reliability of 90% (95% confidence interval). Significance. The PRIMA implant was found to be robust, with in vitro reliability of at least ten years. The PRIMA implant shows durability and functionality for clinically relevant timespans under similar environmental conditions to the human eye. These results require in vivo confirmation.
关键词： implant corrosion,reliability,retinal prosthesis,lifespan,subretinal
更新于2025-09-23 15:21:01
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Translation of a photovoltaic retinal prosthesis
摘要： A silicon-based photovoltaic subretinal prosthesis triggers behavioural responses to pulsed near-infrared light in awake macaques.
关键词： silicon-based,photovoltaic retinal prosthesis,macaques,near-infrared light
更新于2025-09-19 17:13:59
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A review on the current status of retinal prostheses (bionic eye); Pregled informacija o trenutnom stanju retinalnih proteza (bioni?ko oko);
摘要： Argus? II, the first retinal prosthesis is approved for the treatment of patients with retinal pigmentosis. 2011 has received the CE (European Committee) designation and 2013 FDA (Food and Drug Administration) Approval. Retinal prosthesis provides a stable, safe and long-lasting retinal stimulation. The improvement of vision with retinal prosthesis depends on the improvement of the visual resolution, development of the correct neural form for imaging and improvement of the biological compatibility of the device to ensure durability. Once the theme of folklore and science fiction, the idea of returning sight to blind people today is approaching reality.
关键词： retinitis pigmentosa,visual prosthesis,retinal prosthesis
更新于2025-09-16 10:30:52
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Handbook of Bioelectronics (Directly Interfacing Electronics and Biological Systems) || Photovoltaic retinal prosthesis for restoring sight to the blind
摘要： Age-related macular degeneration (AMD) is one of the leading causes of blindness in the developed world, with an incidence of 1:500 in patients aged 55–64, and 1:8 in patients over 85 [1]. Retinitis pigmentosa (RP) is an inherited disease blinding about 1 in every 4000 individuals much earlier in life [2]. In both of these conditions the photoreceptor layer degenerates, while the inner retinal neurons survive to a large extent [3–5]. Electrically activating these neurons provides an alternative route for visual information and raises hope for the restoration of sight to the blind.
关键词： age-related macular degeneration,restoring sight,Photovoltaic retinal prosthesis,blindness,retinitis pigmentosa
更新于2025-09-12 10:27:22
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The Appearance of Phosphenes Elicited Using a Suprachoroidal Retinal Prosthesis
摘要： Phosphenes are the fundamental building blocks for presenting meaningful visual information to the visually impaired using a bionic eye device. The aim of this study was to characterize the size, shape, and location of phosphenes elicited using a suprachoroidal retinal prosthesis. Three patients with profound vision loss due to retinitis pigmentosa were implanted with a suprachoroidal electrode array, which was used to deliver charge-balanced biphasic constant-current pulses at various rates, amplitudes, and durations to produce phosphenes. Tasks assessing phosphene appearance, location, overlap, and the patients’ ability to recognize phosphenes were performed using a custom psychophysics setup. Phosphenes were reliably elicited in all three patients, with marked differences in the reported appearances between patients and between electrodes. Phosphene shapes ranged from simple blobs to complex forms with multiple components in both space and time. Phosphene locations within the visual field generally corresponded to the retinotopic position of the stimulating electrodes. Overlap between phosphenes elicited from adjacent electrodes was observed with one patient, which reduced with increasing electrode separation. In a randomized recognition task, two patients correctly identified the electrode being stimulated for 57.2% and 23% of trials, respectively. Phosphenes of varying complexity were successfully elicited in all three patients, indicating that the suprachoroidal space is an efficacious site for electrically stimulating the retina. The recognition scores obtained with two patients suggest that a suprachoroidal implant can elicit phosphenes containing unique information. This information may be useful when combining phosphenes into more complex and meaningful images that provide functional vision.
关键词： retinal prosthesis,phosphene,bionic vision,suprachoroidal
更新于2025-09-11 14:15:04
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Circularly polarized implantable antenna characterization for retinal prosthesis systems
摘要： We describe a miniaturized antenna design for retinal prosthesis applications that enhances data transfer between the implant and external camera. The circularly polarized and conformal 2.4{2.48 GHz microstrip patch antenna was simulated inside the vitreous humor and is intended for biomedical applications. Modi(cid:12)ed Hilbert and serpentine geometries were used for the proposed implant antenna design. Capacitive radiator loading o?ered miniaturized dimensions of 5.8 (cid:2) 6.5 (cid:2) 2 mm 3 (width (cid:2) height (cid:2) thickness mm 3) . A truncated design enhanced the intrinsic circular polarization characteristics to > 3 dB axial ratio. Polydimethylsiloxane substrate and superstrate materials were used to achieve an S 11 value below {15 dB across the frequency range with biocompatible characteristics. The simulated peak gains for left-hand circular polarization and right-hand circular polarization at 2.45 GHz were {50 dBi and {60 dBi, respectively. These relatively small values were due to the high conductivity of the vitreous humor ( (cid:27) = 1.53 S/m), which imposed signi(cid:12)cant losses. Overall, the proposed antenna had an omnidirectional radiation pattern and + 8.45 dBm input to meet the speci(cid:12)c absorption rate regulation limit.
关键词： miniaturized,circular polarization,retinal prosthesis systems,Implant antenna
更新于2025-09-10 09:29:36
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ADVERSE EVENTS OF THE ARGUS II RETINAL PROSTHESIS
摘要： To analyze and provide an overview of the incidence, management, and prevention of conjunctival erosion in Argus II clinical trial subjects and postapproval patients. This retrospective analysis followed the results of 274 patients treated with the Argus II Retinal Prosthesis System between June 2007 and November 2017, including 30 subjects from the US and European clinical trials, and 244 patients in the postapproval phase. Results were gathered for incidence of a serious adverse event, incidence of conjunctival erosion, occurrence sites, rates of erosion, and erosion timing. Overall, 60% of subjects in the clinical trial subjects versus 83% of patients in the postapproval phase did not experience device- or surgery-related serious adverse events. In the postapproval phase, conjunctival erosion had an incidence rate of 6.2% over 5 years and 11 months. In 55% of conjunctival erosion cases, erosion occurred in the inferotemporal quadrant, 25% in the superotemporal quadrant, and 20% in both. Sixty percent of the erosion events occurred in the first 15 months after implantation, and 85% within the first 2.5 years. Reducing occurrence of conjunctival erosion in patients with the Argus II Retinal Prosthesis requires identification and minimization of risk factors before and during implantation. Implementing inverted sutures at the implant tabs, use of graft material at these locations as well as Mersilene rather than nylon sutures, and accurate Tenon’s and conjunctiva closure are recommended for consideration in all patients.
关键词： conjunctival erosion,retinitis pigmentosa,retinal prosthesis,Argus II,epiretinal implant
更新于2025-09-04 15:30:14