Dataset Information

Assessment of the Electronic Retinal Implant Alpha AMS in Restoring Vision to Blind Patients with End-Stage Retinitis Pigmentosa.

ABSTRACT: PURPOSE:To report the initial efficacy results of the Retina Implant Alpha AMS (Retina Implant AG, Reutlingen, Germany) for partial restoration of vision in end-stage retinitis pigmentosa (RP). DESIGN:Prospective, single-arm, investigator-sponsored interventional clinical trial. Within-participant control comprising residual vision with the retinal implant switched ON versus OFF in the implanted eye. PARTICIPANTS:The Retina Implant Alpha AMS was implanted into the worse-seeing eye of 6 participants with end-stage RP and no useful perception of light vision. Eligibility criteria included previous normal vision for ?12 years and no significant ocular or systemic comorbidity. METHODS:Vision assessments were scheduled at 1, 2, 3, 6, 9, and 12 months postimplantation. They comprised tabletop object recognition tasks, a self-assessment mobility questionnaire, and screen-based tests including Basic Light and Motion (BaLM), grating acuity, and greyscale contrast discrimination. A full-field stimulus test (FST) was also performed. MAIN OUTCOME MEASURES:Improvement in activities of daily living, recognition tasks, and assessments of light perception with the implant ON compared with OFF. RESULTS:All 6 participants underwent successful implantation. Light perception and temporal resolution with the implant ON were achieved in all participants. Light localization was achieved with the implant ON in all but 1 participant (P4) in whom the chip was not functioning optimally because of a combination of iatrogenic intraoperative implant damage and incorrect implantation. Implant ON correct grating detections (which were at chance level with implant OFF) were recorded in the other 5 participants, ranging from 0.1 to 3.33 cycles/degree on 1 occasion. The ability to locate high-contrast tabletop objects not seen with the implant OFF was partially restored with the implant ON in all but 1 participant (P4). There were 2 incidents of conjunctival erosion and 1 inferotemporal macula-on retinal detachment, which were successfully repaired, and 2 incidents of inadvertent damage to the implant during surgery (P3 and P4). CONCLUSIONS:The Alpha AMS subretinal implant improved visual performance in 5 of 6 participants and has exhibited ongoing function for up to 24 months. Although implantation surgery remains challenging, new developments such as OCT microscope guidance added refinements to the surgical technique.

SUBMITTER: Edwards TL

PROVIDER: S-EPMC5818267 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Assessment of the Electronic Retinal Implant Alpha AMS in Restoring Vision to Blind Patients with End-Stage Retinitis Pigmentosa.

Edwards Thomas L TL Cottriall Charles L CL Xue Kanmin K Simunovic Matthew P MP Ramsden James D JD Zrenner Eberhart E MacLaren Robert E RE

Ophthalmology 20171027 3

<h4>Purpose</h4>To report the initial efficacy results of the Retina Implant Alpha AMS (Retina Implant AG, Reutlingen, Germany) for partial restoration of vision in end-stage retinitis pigmentosa (RP).<h4>Design</h4>Prospective, single-arm, investigator-sponsored interventional clinical trial. Within-participant control comprising residual vision with the retinal implant switched ON versus OFF in the implanted eye.<h4>Participants</h4>The Retina Implant Alpha AMS was implanted into the worse-see ...[more]

PMID: 29110946

Similar Datasets

Project description:Purpose: We assessed the safety and efficacy of a technically advanced subretinal electronic implant, RETINA IMPLANT Alpha AMS, in end stage retinal degeneration in an interim analysis of two ongoing prospective clinical trials. The purpose of this article is to describe the interim functional results (efficacy). Methods: The subretinal visual prosthesis RETINA IMPLANT Alpha AMS (Retina Implant AG, Reutlingen, Germany) was implanted in 15 blind patients with hereditary retinal degenerations at four study sites with a follow-up period of 12 months (www.clinicaltrials.gov NCT01024803 and NCT02720640). Functional outcome measures included (1) screen-based standardized 2- or 4-alternative forced-choice (AFC) tests of light perception, light localization, grating detection (basic grating acuity (BaGA) test), and Landolt C-rings; (2) gray level discrimination; (3) performance during activities of daily living (ADL-table tasks). Results: Implant-mediated light perception was observed in 13/15 patients. During the observation period implant mediated localization of visual targets was possible in 13/15 patients. Correct grating detection was achieved for spatial frequencies of 0.1 cpd (cycles per degree) in 4/15; 0.33 cpd in 3/15; 0.66 cpd in 2/15; 1.0 cpd in 2/15 and 3.3 cpd in 1/15 patients. In two patients visual acuity (VA) assessed with Landolt C- rings was 20/546 and 20/1111. Of 6 possible gray levels on average 4.6 ± 0.8 (mean ± SD, n = 10) were discerned. Improvements (power ON vs. OFF) of ADL table tasks were measured in 13/15 patients. Overall, results were stable during the observation period. Serious adverse events (SAEs) were reported in 4 patients: 2 movements of the implant, readjusted in a second surgery; 4 conjunctival erosion/dehiscence, successfully treated; 1 pain event around the coil, successfully treated; 1 partial reduction of silicone oil tamponade leading to distorted vision (silicon oil successfully refilled). The majority of adverse events (AEs) were transient and mostly of mild to moderate intensity. Conclusions: Psychophysical and subjective data show that RETINA IMPLANT Alpha AMS is reliable, well tolerated and can restore limited visual functions in blind patients with degenerations of the outer retina. Compared with the previous implant Alpha IMS, longevity of the new implant Alpha AMS has been considerably improved. Alpha AMS has meanwhile been certified as a commercially available medical device, reimbursed in Germany by the public health system.

Project description:PurposeThere have been few systematic reports of vision-related activity limitations of people with retinitis pigmentosa (RP). We report a merging of data from the National Eye Institute Visual Function Questionnaire (NEI-VFQ) obtained in five previous studies. We asked whether the Vision Function Scale (VFS; Pesudovs et al., 2010) which was developed for cataract patients would apply in this new population (condition).MethodsFive hundred ninety-four individuals completed a total of 1753 questionnaires, with 209 participants providing responses over at least 4?years. Rasch analysis showed that the 15-item VFS was poorly targeted. A new instrument created by adding four driving-related items to the VFS had better targeting. As an indirect validation, VFS-plus person scores were compared to visual field area measured using a Goldmann perimeter, to the summed score for the combined 30-2 and 30/60-1 Humphrey Field Analyzer programs (HFA), to 30-Hz full-field cone electroretinogram (ERG) amplitude, and to ETDRS visual acuity. Changes in VFS-plus person scores with age and between four common heredity groups were also examined.ResultsThe Rasch model of responses to the 19 VFS-plus items had person and item separation of 2.66 and 24.43 respectively. The VFS-plus person scores were related to each vision measure (p?<?0.001). Over a five-year period, there was a reduction in person scores of 0.5 logits (p?<?0.001). Person scores fell by an average of 0.34 logits per decade (p?<?0.0001). Participants with an X-linked hereditary pattern had, on average, lower person scores (p?<?0.001).ConclusionsThe VFS-plus instrument quantified a highly-significant annual reduction in perceived vision-related ability over a five-year period. The outcome was consistent with clinical measures of vision, and detected lower perceived vision-related ability in participants with X-linked disease. It may be of use in future studies, but this needs to be tested in a representative population sample.

Project description:Retinitis pigmentosa is a group of genetic disorders that involves the breakdown and loss of photoreceptors in the retina, resulting in progressive retinal degeneration and eventual blindness. The Argus II Retinal Prosthesis System is the only currently available surgical implantable device approved by Health Canada. It has been shown to improve visual function in patients with severe visual loss from advanced retinitis pigmentosa. The objective of this analysis was to examine the clinical effectiveness, cost-effectiveness, budget impact, and safety of the Argus II system in improving visual function, as well as exploring patient experiences with the system.We performed a systematic search of the literature for studies examining the effects of the Argus II retinal prosthesis system in patients with advanced retinitis pigmentosa, and appraised the evidence according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) Working Group criteria, focusing on visual function, functional outcomes, quality of life, and adverse events. We developed a Markov decision-analytic model to assess the cost-effectiveness of the Argus II system compared with standard care over a 10-year time horizon. We also conducted a 5-year budget impact analysis. We used a qualitative design and an interview methodology to examine patients' lived experience, and we used a modified grounded theory methodology to analyze information from interviews. Transcripts were coded, and themes were compared against one another.One multicentre international study and one single-centre study were included in the clinical review. In both studies, patients showed improved visual function with the Argus II system. However, the sight-threatening surgical complication rate was substantial. In the base-case analysis, the Argus II system was cost-effective compared with standard care only if willingness-to-pay was more than $207,616 per quality-adjusted life-year. The 5-year budget impact of funding the Argus II system ranged from $800,404 to $837,596. Retinitis pigmentosa significantly affects people's ability to navigate physical and virtual environments. Argus II was described as enabling the fundamental elements of sight. As such, it had a positive impact on quality of life for people with retinitis pigmentosa.Based on evidence of moderate quality, patients with advanced retinitis pigmentosa who were implanted with the Argus II retinal prosthesis system showed significant improvement in visual function, real-life functional outcomes, and quality of life, but there were complications associated with the surgery that could be managed through standard ophthalmologic treatments. The costs for the technology are high.

Dataset Information

Assessment of the Electronic Retinal Implant Alpha AMS in Restoring Vision to Blind Patients with End-Stage Retinitis Pigmentosa.

Publications

Assessment of the Electronic Retinal Implant Alpha AMS in Restoring Vision to Blind Patients with End-Stage Retinitis Pigmentosa.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets