Visual Activity Evoked by Infrared in Humans After Dark Adaptation
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|ClinicalTrials.gov Identifier: NCT02909985|
Recruitment Status : Completed
First Posted : September 21, 2016
Last Update Posted : September 21, 2016
This 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.
|Condition or disease||Intervention/treatment||Phase|
|Age Related Macular Degeneration Retinitis Pigmentosa Congenital Stationary Night Blindness Colorblindness||Other: Tungsten halogen light with narrow bandpass filters Other: ERG Other: VEP||Not Applicable|
Show Detailed Description
|Study Type :||Interventional (Clinical Trial)|
|Actual Enrollment :||29 participants|
|Intervention Model:||Parallel Assignment|
|Official Title:||Visual Activity Evoked by Infrared in Humans After Dark Adaptation|
|Study Start Date :||September 2015|
|Actual Primary Completion Date :||August 2016|
|Actual Study Completion Date :||August 2016|
Experimental: Visual response to IR
For both groups, as intensity in increased from 0 to 12 V, participants will say if/when they see a visual response to infrared light from a broad band Tungsten halogen light with narrow bandpass filters ranging from 850 nm to 1400 nm. At the end of three trials per filter, the intensity will be turned up to 12 V, and participants will describe the color they see.
Other: Tungsten halogen light with narrow bandpass filters
As intensity in increased from 0 to 12 V, participants will say if/when they see a visual response to infrared light from a broad band tungsten halogen light source that passes through narrow bandpass filters ranging from 850 nm to 1400 nm. At the end of three trials per filter, the intensity will be turned up to 12 V, and participants will describe the color they see.
Participants will undergo electroretinography using both normal settings and infrared as the stimuli.
Experimental: Visual Evoke Potential Test
Participants will undergo visual evoke potential tests using both normal settings and infrared as the stimuli.
- Visual perception to infrared [ Time Frame: Up to one year ]Ability to detect IR visually through subjective measurement
- Description of color [ Time Frame: Up to one year ]Description of color to IR stimulus
- Electroretinography [ Time Frame: Up to one year ]Electroretinography response to infrared stimulus
- Visual Evoke Potential [ Time Frame: Up to one year ]Visual Evoke Potential to infrared stimulus
To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT02909985
|United States, New Mexico|
|University of New Mexico|
|Albuquerque, New Mexico, United States, 87131-0001|
|Principal Investigator:||Leslie Olivia Hopkins, MD||University of New Mexico|