Visual Activity Evoked by Infrared in Humans After Dark Adaptation
Age Related Macular DegenerationRetinitis Pigmentosa2 moreThis pilot study will evaluate the visual response to infrared (IR) in humans after dark adaptation. The investigators plan to determine which wavelength and intensity the human eye is most sensitive too, using a broad spectrum light source and wavelength-specific bandpass filters. The investigators will then evaluate the electrophysiologic response in healthy humans to IR, followed by studies in those with specific retinal diseases. The long-term goal of this research is to better understand the role that IR plays in visual function, and whether this can be manipulated to allow for vision in certain retinal pathologies that result from loss of photoreceptor cells. The investigators central objective is to test the electrophysiologic response to IR in the dark-adapted retinal and visual pathways. The investigators central hypothesis is that IR evokes a visual response in humans after dark adaptation, and the characteristics of this response suggest transient receptor potential (TRP) channel involvement. The investigators rationale is that a better understanding of how IR impacts vision may allow for an alternative mechanism for vision in a number of diseases that cause blindness from the degradation or loss of function of photoreceptor cells. The investigators will test the investigators hypothesis with the following Aims: Aim 1: To determine the optimal IR wavelength for visual perception in dark-adapted human participants. The investigators hypothesize that the healthy human eye will detect IR irradiation, with a maximum sensitivity at a specific wavelength. Using a broad-spectrum light source with wavelength-specific bandpass filters, the spectral range of visual perception to IR will be evaluated. The same will be done on colorblind participants. Aim 2: To test the electrophysiologic response to IR in healthy humans after dark adaptation. The investigators hypothesize that IR will elicit an amplitude change on electroretinography (ERG) and visual evoked potential (VEP) responses after dark adaptation in healthy human participants. Participants will be tested with both test modalities to evaluate their response to IR. Aim 3: To test the electrophysiologic response to IR after dark adaptation in humans with certain retinal diseases. Participants with retinitis pigmentosa, age related macular degeneration and congenital stationary night blindness, will be tested. Results will be compared to baselines and to those of healthy participants. The investigators hypothesize that there will be a response to IR on ERG and VEP, which will provide clues to the retinal cell layer location of the response to IR and the nature of potential TRP channel involvement.
DHA and X-Linked Retinitis Pigmentosa
Retinitis PigmentosaX-linked Genetic DiseasesPurpose: Retinitis pigmentosa (RP) is characterized by progressive loss of visual function due to specific genetic mutations. This trial is focused on patients with one of the most severe forms of the disease, X-linked inherited RP (XLRP). This disease is characterized by early onset (typically loss of night vision as a child) followed by loss of peripheral vision as a teenager and young adult. There is no male-to-male transmission of the disease in the family. There is no cure for RP and treatment options are limited. Two clinical trials have not found a benefit from nutritional supplementation with the long-chain polyunsaturated fatty acid, docosahexaenoic acid (DHA), at low daily doses although there is evidence that it slows disease progression in certain instances. In this clinical trial, we propose that a high dose nutritional DHA supplement will slow the loss of visual function and preserve usable vision in patients with XLRP. This study is a 4-year placebo-controlled randomized clinical trial meaning that patients have a 50-50 chance of receiving placebo or experimental treatment. A total of 66 patients will be enrolled; 33 will receive placebo and 33 will receive the treatment. Entry criteria include diagnosis of XLRP by an ophthalmologist, age 7 to 32 years, male, sufficient visual function such that disease progression can be followed for the entire duration of the trial, and a willingness to visit the testing site (Dallas, TX) once a year. Annual visual function testing includes ETDRS visual acuity, full-field and multifocal electroretinography (ERG), static peripheral visual fields, and fundus photography. Cone ERG function is the primary outcome measure. Funding Source - FDA, Foundation Fighting Blindness, DSM Nutritionals
A Study of Cidofovir in HIV-Infected Children With Cytomegalovirus (CMV) Disease
Cytomegalovirus InfectionsCytomegalovirus Retinitis1 morePart A: To determine the safety and pharmacokinetics of sequential single doses of cidofovir in HIV-infected children with end-organ cytomegalovirus (CMV) disease. Part B: To determine the safety (including time to progression of CMV retinitis by retinal exam), pharmacokinetics, and long-term (6 months) tolerance of multiple-dose cidofovir in HIV-infected children with CMV retinitis. Part B: To determine the effect of multiple-dose cidofovir on the virologic parameters of CMV retinitis (viral load, shedding, and resistance to antiviral agents). [AS PER AMENDMENT 1/7/98: To determine the safety, tolerance and pharmacokinetics of sequential single doses of cidofovir in HIV-infected children with CMV retinitis. To determine the safety (including time to progression of CMV retinitis by retinal exam), pharmacokinetics, and long-term (6-month) tolerance of multiple doses of cidofovir in HIV-infected children with CMV retinitis.] While the intravenous formulation of cidofovir has been approved for the treatment of CMV retinitis in HIV-infected individuals, information is limited regarding its safety and tolerance in HIV-infected children. Intravenous cidofovir requires less frequent administration for both induction and maintenance therapy of CMV retinitis than other currently available therapies. If found to be safe and well tolerated in HIV-infected children with CMV retinitis, intravenous cidofovir would add significantly to agents available to treat this debilitating opportunistic infection.
Exercise and RP (AVAMC and Emory)
Retinitis PigmentosaThe purpose of this study is to look in humans at the relationship between moderate or little exercise and their potential effects on the retina in patients with Retinitis Pigmentosa (RP).
RETINA IMPLANT Alpha AMS in Blind Patients With Retinitis Pigmentosa
Retinitis PigmentosaThe goal of this study is to transfer the surgical implantation technique and evaluate the safety and effectiveness of the RETINA IMPLANT Alpha AMS to restore limited visual function and functional vision in blind Retinitis Pigmentosa (RP) patients who are at the Light Perception (LP) or No Light Perception vision level (NLP). The safety of the implantation procedure and the long-term presence of the RETINA IMPLANT Alpha AMS will be assessed with clinical exams and objective clinical tests for the absence of any new permanent damage to the structure and function of the implanted eye with no permanent injury to the health and/or well being of the implanted patient as a result of the surgical procedure or presence of the implant. The effectiveness of the RETINA IMPLANT Alpha AMS will be evaluated by measuring limited visual function and functional vision in implanted subjects with the device "ON" and "OFF" in a randomized order. The ability to restore limited vision in blind RP patients with LP vision or NLP will reduce their disability and morbidity and provide a viable option to combat their disease and improve their lives.
Transcorneal Electrical Stimulation for the Treatment of Retinitis Pigmentosa - a Safety and Efficacy...
Retinitis PigmentosaSeveral studies have shown that TES in RP patients may help to slow the progressive deterioration of this degenerative disease. The end point of this clinical trial is to slow or stop disease progression with weekly treatment using TES for 1 year.
Argus II Retinal Prosthesis System - Better Vision RP Study
Retinitis PigmentosaThe study is conducted to evaluate the safety and benefit of the Argus II System in a selected patient population with advanced Retinitis Pigmentosa who have a measurable central residual visual field smaller than or equal to 5 degrees radius.
A Study of Foscarnet in the Treatment of Cytomegalovirus (CMV) of the Eyes in Patients With AIDS...
Cytomegalovirus RetinitisHIV InfectionsTo study the safety and effectiveness of foscarnet in the treatment of AIDS patients who have active infection with cytomegalovirus (CMV) that is causing inflammation of the retina (retinitis). In addition, these patients cannot be treated with ganciclovir (DHPG) because of its toxic effect on the body's blood-forming cells or because white blood cell or platelet counts were too low. CMV is a common virus, which can cause blindness and death in AIDS patients. Previous studies demonstrate that foscarnet has been effective in both AIDS and non-AIDS patients with CMV infection. Although treatment with ganciclovir (DHPG) is also effective, a significant toxicity leading to dose-limiting neutropenia (low white blood cell count) in one third of treated patients has been associated with the drug. Based on the serious nature of CMV retinitis and the lack of alternative drug therapies for DHPG-sensitive patients, the present study will evaluate the safety and efficacy of intravenous (IV) foscarnet in AIDS patients with CMV retinitis.
In Depth Observational Clinical Trial Of Retinitis Pigmentosa Patients
Retinitis PigmentosaTypically, clinical research participation favors a specific demographic group, and little research exists on how trial attributes affect participation. As such, this study seeks to analyze data from different demographic groups and check for recurring trends that could provide valuable insights for future retinitis pigmentosa patients.
Intravitreal Injection of SeeQ CdSe 655 Alt Nanoparticles for Patients With Degenerative Retinal...
Retinitis PigmentosaThis study was a prospective, open label feasibility study conducted at a single clinical site (APEC, Mexico City) to evaluate the safety and preliminary effectiveness of the SeeQ device, with each patient's serving as his/her own contralateral control.