Macular Degeneration, Dry, Primary Open-angle Glaucoma
Conditions
Keywords
light stimulation, retinal photoreceptors, light adaptation, functional optical coherence tomography, optophysiology, intrinsic optical signals
Brief summary
It has been shown that reactions of human retinal photoreceptors to a light stimulus can be measured with custom-made, research prototype optical coherence tomography (OCT) systems. This can be used as a biomarker for the function of the photoreceptors. Due to the high technical demands on the system, however, the technique is currently not available for clinical purposes. In this pilot study a protocol to measure changes in retinal photoreceptor layer thickness before and after light stimulation shall be developed based on a commercial OCT system and newly developed algorithms. Other variables, such as circadian processes shall be investigated as well. After measurements in healthy volunteers, the protocol is planned to be applied in patients with primary open angle glaucoma (POAG) and age-related macular degeneration (AMD) to test for feasibility of the method in these patient groups.
Interventions
OTHERWhite light stimulation
Stimulation of the retina with white light
Sponsors
Medical University of Vienna
Study design
Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* men and women aged over 18 years * signed informed consent form * ametropia below 3 diopters * ability and willingness to follow instructions for healthy volunteers: * normal ophthalmologic findings for primary open angle glaucoma patients (POAG): * diagnosed POAG * MD \<= 10 dB for age-related macular degeneration (AMD): * diagnosed dry AMD * diagnosed stage II or stage III AMD
Exclusion criteria
* Presence of any abnormalities preventing reliable measurements * Ocular inflammation and ocular disease interfering with the study aims * Use of photosensitizing medication (phototoxic drugs, photoallergic drugs) in the 3 months preceding the study * Presence of any condition with the possibility of causing photosensitivity, including systemic lupus erythematosus SLE, Porphyria, Vitiligo, Xeroderma Pigmentosum and Albinism * Presence of any form of epilepsy * Ocular surgery in the 3 months preceding the study * Pregnancy, planned pregnancy or lactating * Any medical or surgical history, disorder or disease such as acute or chronic severe organic disease
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Light stimulation | 1 day | Optical path length changes between inner segment outer segment junction and retinal pigment epithelium (RPE) will be measured with OCT in 15 healthy volunteers, 10 POAG patients and 10 AMD patients before and after light stimulation |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Light stimulation of contralateral eye | 1 day | Optical path length changes between inner segment outer segment junction and retinal pigment epithelium (RPE) will be measured with OCT in 15 healthy volunteers, 10 POAG patients and 10 AMD patients before and after light stimulation in the contralateral eye |
| Difference in photoreceptor layer thickness over the course of 8 hours | 8 hours | Influence of circadian rhythm on the length of retinal photoreceptor outer segments |
| En face maps | 1 day | test an algorithm for production of en face maps of retinal photoreceptor outer segment length |
Countries
Austria
Contacts
Primary ContactDoreen Schmidl, MD,PhD
Outcome results
None listed