Retinal safety of near infrared radiation in photovoltaic restoration of sight

Lorach, Henri; Wang, J.; Lee, D. Y.; Dalal, Roopa; Huie, Phil; Palanker, Daniel

doi:10.1364/boe.7.000013

Cited by 30 publications

(31 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…According to the thermal safety standard for active implantable medical devices (ISO 14708-1 / EN 45502-1), the maximum temperature on the surface of the implant should not exceed 2 °C above the normal surrounding body temperature of 37 °C 31 . We measured in air the increase in temperature on the POLYRETINA surface (Fig.…”

Section: Resultsmentioning

confidence: 99%

Design and validation of a foldable and photovoltaic wide-field epiretinal prosthesis

et al. 2018

View full text Add to dashboard Cite

Retinal prostheses have been developed to fight blindness in people affected by outer retinal layer dystrophies. To date, few hundred patients have received a retinal implant. Inspired by intraocular lenses, we have designed a foldable and photovoltaic wide-field epiretinal prosthesis (named POLYRETINA) capable of stimulating wireless retinal ganglion cells. Here we show that within a visual angle of 46.3 degrees, POLYRETINA embeds 2215 stimulating pixels, of which 967 are in the central area of 5 mm, it is foldable to allow implantation through a small scleral incision, and it has a hemispherical shape to match the curvature of the eye. We demonstrate that it is not cytotoxic and respects optical and thermal safety standards; accelerated ageing shows a lifetime of at least 2 years. POLYRETINA represents significant progress towards the improvement of both visual acuity and visual field with the same device, a current challenging issue in the field.

show abstract

Section: Resultsmentioning

confidence: 99%

Design and validation of a foldable and photovoltaic wide-field epiretinal prosthesis

et al. 2018

View full text Add to dashboard Cite

show abstract

“…The threshold in the RCS rats was found to be ~ 1 mW/mm 2 , exceeding the natural retinal irradiance by a factor of 1,000 (Lorach et al, 2015b). The investigators argue that the pulsed delivery of NIR at this intensity level results in an average irradiance far below the maximum permissible dose of NIR to retina for chronic exposure (Lorach et al, 2016). Since it's not clear from the group's publications whether long term changes occurred at the implant-retina interface, physically and functionally, their arguments in terms of ocular safety awaits further verification.…”

Section: Photovoltaic Retinal Prosthesismentioning

confidence: 95%

Retinal stimulation strategies to restore vision: Fundamentals and systems

Lan

Weiland

Roska

et al. 2016

Progress in Retinal and Eye Research

239

185

View full text Add to dashboard Cite

Retinal degeneration, a leading cause of blindness worldwide, is primarily characterized by the dysfunctional/degenerated photoreceptors that impair the ability of the retina to detect light. Our group and others have shown that bioelectronic retinal implants restore useful visual input to those who have been blind for decades. This unprecedented approach of restoring sight demonstrates that patients can adapt to new visual input, and thereby opens up opportunities to not only improve this technology but also develop alternative retinal stimulation approaches. These future improvements or new technologies could have the potential of selectively stimulating specific cell classes in the inner retina, leading to improved visual resolution and color vision. In this review we will detail the progress of bioelectronic retinal implants and future devices in this genre as well as discuss other technologies such as optogenetics, chemical photoswitches, and ultrasound stimulation. We will discuss the principles, biological aspects, technology development, current status, clinical outcomes/prospects, and challenges for each approach. The review will cover functional imaging documented cortical responses to retinal stimulation in blind patients.

show abstract

“…Detailed studies of retinal heating with and without silicon implants under various illumination conditions have shown that under typical use conditions, the temperature increase associated with activation of a subretinal photovoltaic implant is not expected to exceed 0.5°C, well within the safety limits for chronic use [70]. …”

Section: Approaches To Retinal Prostheticsmentioning

confidence: 99%

Electronic approaches to restoration of sight

Goetz

Palanker

2016

Rep. Prog. Phys.

View full text Add to dashboard Cite

Retinal prostheses are a promising means for restoring sight to patients blinded by the gradual atrophy of photoreceptors due to retinal degeneration. They are designed to reintroduce information into the visual system by electrically stimulating surviving neurons in the retina. This review outlines the concepts and technologies behind two major approaches to retinal prosthetics: epiretinal and subretinal. We describe how the visual system responds to electrical stimulation. We highlight major differences between direct encoding of the retinal output with epiretinal stimulation, and network-mediated response with subretinal stimulation. We summarize results of pre-clinical evaluation of prosthetic visual functions in- and ex-vivo, as well as the outcomes of current clinical trials of various retinal implants. We also briefly review alternative, non-electronic, approaches to restoration of sight to the blind, and conclude by suggesting some perspectives for future advancement in the field.

show abstract

Retinal safety of near infrared radiation in photovoltaic restoration of sight

Cited by 30 publications

References 22 publications

Design and validation of a foldable and photovoltaic wide-field epiretinal prosthesis

Design and validation of a foldable and photovoltaic wide-field epiretinal prosthesis

Retinal stimulation strategies to restore vision: Fundamentals and systems

Electronic approaches to restoration of sight

Contact Info

Product

Resources

About