Long-Term Results from an Epiretinal Prosthesis to Restore Sight to the Blind

PurposeRetinitis pigmentosa (RP) is a group of inherited retinal degenerations leading to blindness due to photoreceptor loss. Retinitis pigmentosa is a rare disease, affecting only approximately 100 000 people in the United States. There is no cure and no approved medical therapy to slow or reverse RP. The purpose of this clinical trial was to evaluate the safety, reliability, and benefit of the Argus II Retinal Prosthesis System (Second Sight Medical Products, Inc, Sylmar, CA) in restoring some visual function to subjects completely blind from RP. We report clinical trial results at 1 and 3 years after implantation.DesignThe study is a multicenter, single-arm, prospective clinical trial.ParticipantsThere were 30 subjects in 10 centers in the United States and Europe. Subjects served as their own controls, that is, implanted eye versus fellow eye, and system on versus system off (native residual vision).MethodsThe Argus II System was implanted on and in a single eye (typically the worse-seeing eye) of blind subjects. Subjects wore glasses mounted with a small camera and a video processor that converted images into stimulation patterns sent to the electrode array on the retina.Main Outcome MeasuresThe primary outcome measures were safety (the number, seriousness, and relatedness of adverse events) and visual function, as measured by 3 computer-based, objective tests.ResultsA total of 29 of 30 subjects had functioning Argus II Systems implants 3 years after implantation. Eleven subjects experienced a total of 23 serious device- or surgery-related adverse events. All were treated with standard ophthalmic care. As a group, subjects performed significantly better with the system on than off on all visual function tests and functional vision assessments.ConclusionsThe 3-year results of the Argus II trial support the long-term safety profile and benefit of the Argus II System for patients blind from RP. Earlier results from this trial were used to gain approval of the Argus II by the Food and Drug Administration and a CE mark in Europe. The Argus II System is the first and only retinal implant to have both approvals

Retinal Prostheses: Patient Selection and Screening

The Argus II surgeon must ensure that the patient selected for device implantation meets all of the eligibility criteria contained in the product label, there are no contraindications to device placement, the patient’s level of residual vision contributes to a favorable risk/benefit profile, and the patient’s motivations, expectations, cognitive and communication skills, and physical abilities are likely to contribute to receiving benefit from the device. Screening typically involves a standardized survey, patient interview, and complete eye exam with biometry to determine axial length, B-scan ultrasonography to rule out a staphyloma, and macular optical coherence tomography to evaluate inner retinal anatomy

Atypical chronic central serous chorioretinopathy with cystoid macular edema: Therapeutic response to medical and laser therapy.

PurposeTo describe an atypical case of chronic central serous chorioretinopathy (CSCR).MethodsA 58-year-old man with longstanding, bilateral visual impairment was self-referred for a second opinion.ResultsFindings by direct ophthalmoscopy, optical coherence tomography, fluorescein angiography, and fundus autofluorescence (FAF) were suggestive of atypical, chronic CSCR. Treatment with oral anti-mineralocorticoids resulted in moderate improvement, and photodynamic therapy (PDT) had minimal effect.ConclusionChronic CSCR may lack cardinal features of CSCR. Once retinal degenerative changes ensue, current treatments may not be effective in improving anatomical and visual outcomes in patients with chronic CSCR

Atypical chronic central serous chorioretinopathy with cystoid macular edema: Therapeutic response to medical and laser therapy.

PurposeTo describe an atypical case of chronic central serous chorioretinopathy (CSCR).MethodsA 58-year-old man with longstanding, bilateral visual impairment was self-referred for a second opinion.ResultsFindings by direct ophthalmoscopy, optical coherence tomography, fluorescein angiography, and fundus autofluorescence (FAF) were suggestive of atypical, chronic CSCR. Treatment with oral anti-mineralocorticoids resulted in moderate improvement, and photodynamic therapy (PDT) had minimal effect.ConclusionChronic CSCR may lack cardinal features of CSCR. Once retinal degenerative changes ensue, current treatments may not be effective in improving anatomical and visual outcomes in patients with chronic CSCR

The tipping point: Tamoxifen toxicity, central serous chorioretinopathy, and the role of estrogen and its receptors

Purpose: To describe a case of tamoxifen toxicity superimposed on central serous chorioretinopathy (CSCR). We review the role of estrogen and the effect of tamoxifen on ocular tissues. Observations: A 32-year-old Hispanic female with infiltrating ductal carcinoma of the left breast (T2N1M0, triple-positive), status post chemotherapy and bilateral mastectomy, presented with complaint of a floater and decreased central vision of the right eye (OD). Symptoms began three weeks after initiating tamoxifen and five months after the last cycle of chemotherapy and dexamethasone. Visual acuity (VA) was 20/30 OD at presentation. Clinical examination and multimodal imaging revealed subretinal fluid (SRF) and pigment epithelial detachment (PED) suggestive of CSCR. After one month of monitoring, VA improved to 20/20; there was SRF resolution, small PED, and focal ellipsoid zone (EZ) band loss. Two weeks later, after undergoing surgery and starting a topical steroid, she returned with count fingers (CF) VA and large SRF OD. Steroid cessation improved SRF after one month, but VA was unchanged. Tamoxifen was discontinued, and VA improved to 20/100 with near-complete resolution of SRF at three weeks, and significant reduction in choroidal thickness at two months. At final follow-up, VA was 20/200, and there was focal EZ band loss sub-foveally, minimal SRF, and small PED. Conclusions and Importance: Treatment with tamoxifen may lead to ocular toxicity and can complicate the recovery course of patients affected with CSCR. Variations in levels of the estrogen receptor-alpha (ER-α) and treatment with tamoxifen (ER-α partial agonist) may lead to loss of the protective effect of estrogen in the retinal pigment epithelial cells in premenopausal women. Furthermore, tamoxifen toxicity can lead to focal photoreceptor loss. Treatment in these cases should be coordinated together with the oncologist

Quantitative assessment of choriocapillaris flow deficits in diabetic retinopathy: A swept-source optical coherence tomography angiography study.

PurposeTo quantitatively assess choriocapillaris (CC) flow deficits in eyes with diabetic retinopathy (DR) using swept-source optical coherence tomography angiography (SS-OCTA).MethodsDiabetic subjects with different stages of DR and age-matched healthy subjects were recruited and imaged with SS-OCTA. The en face CC blood flow images were generated using previously published and validated algorithms. The percentage of CC flow deficits (FD%) and the mean CC flow deficit size were calculated in a 5-mm-diameter circle centered on the fovea from the 6×6-mm scans.ResultsForty-five diabetic subjects and 27 control subjects were included in the study. The CC FD% in diabetic eyes was on average 1.4-fold greater than in control eyes (12.34±4.14% vs 8.82±2.61%, P ConclusionsCC perfusion in DR can be objectively and quantitatively assessed with FD% and FD size. In the macular region, both CC FD% and CC FD size are increased in eyes with DR. SS-OCTA provides new insights for the investigations of CC perfusion status in diabetes in vivo

Quantitative microvascular analysis of retinal venous occlusions by spectral domain optical coherence tomography angiography.

PURPOSE:To quantitatively evaluate the retinal microvasculature in human subjects with retinal venous occlusions (RVO) using optical coherence tomography angiography (OCTA). DESIGN:Retrospective, cross-sectional, observational case series. PARTICIPANTS:Sixty subjects (84 eyes) were included (20 BRVO, 14 CRVO, 24 unaffected fellow eyes, and 26 controls). METHODS:OCTA was performed on a prototype, spectral domain-OCTA system in the 3x3mm central macular region. Custom software was used to quantify morphology and density of retinal capillaries using four quantitative parameters. The vasculature of the segmented retinal layers and nonsegmented whole retina were analyzed. MAIN OUTCOME MEASURES:Fractal dimension (FD), vessel density (VD), skeletal density (SD), and vessel diameter index (VDI) within the segmented retinal layers and nonsegmented whole retina vasculature. RESULTS:Nonsegmented analysis of RVO eyes demonstrated significantly lower FD (1.64±0.01 vs 1.715±0.002; p<0.001), VD (0.32±0.01 vs 0.432±0.002; p<0.001), and SD (0.073±0.004 vs 0.099±0.001; p<0.001) compared to controls. Compared to the fellow eye, FD, VD and SD were lower (p<0.001), and VDI was higher (p<0.001). FD, VD, and SD progressively decreased as the extent (or type) of RVO increased (control vs BRVO vs CRVO; p<0.001). In the unaffected fellow eye FD, VD and SD showed significant differences when compared to control eyes or affected RVO eyes (p<0.001). CONCLUSIONS:Quantitative OCTA of the central 3x3mm macular region demonstrates significant differences in capillary density and morphology among subjects with BRVO and CRVO compared to controls or unaffected fellow eyes in all vascular layers. The unaffected fellow eyes also demonstrate significant differences when compared to controls. OCTA allows for noninvasive, layer-specific, quantitative evaluation of RVO-associated microvascular changes

Improvements in vision-related quality of life in blind patients implanted with the Argus II Epiretinal Prosthesis

The purpose of this analysis is to report the change in quality of life (QoL) after treatment with the Argus II Epiretinal Prosthesis in patients with end-stage retinitis pigmentosa