Retinal Photoreceptor Outer Segment Length Before and After Light Stimulation - a Pilot Study

• ClinicalTrials.gov Identifier: NCT03921931
• Recruitment Status: Recruiting
• First Posted: April 19, 2019
• Last Update Posted: February 24, 2021
• Sponsor: Medical University of Vienna
• Information provided by (Responsible Party): Doreen Schmidl, Medical University of Vienna

Study Description

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.

Condition or disease	Intervention/treatment	Phase
Macular Degeneration, Dry; Primary Open-angle Glaucoma	Other: White light stimulation	Not Applicable

Study Design

• Study Type: Interventional (Clinical Trial)
• Estimated Enrollment: 35 participants
• Allocation: Non-Randomized
• Intervention Model: Parallel Assignment
• Masking: None (Open Label)
• Primary Purpose: Basic Science
• Official Title: Assessment of Retinal Photoreceptor Outer Segment Length With Optical Coherence Tomography Before and After Light Stimulation - a Pilot Study
• Actual Study Start Date: November 26, 2018
• Estimated Primary Completion Date: May 31, 2021
• Estimated Study Completion Date: May 31, 2021

Arms and Interventions

Arm	Intervention/treatment
Experimental: healthy volunteers; light stimulation	Other: White light stimulation; Stimulation of the retina with white light
Experimental: primary open angle glaucoma patients; light stimulation	Other: White light stimulation; Stimulation of the retina with white light
Experimental: age-related macular degeneration patients; light stimulation	Other: White light stimulation; Stimulation of the retina with white light

Outcome Measures

Primary Outcome Measures :

1. Light stimulation [ Time Frame: 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 Outcome Measures :

1. Light stimulation of contralateral eye [ Time Frame: 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
2. Difference in photoreceptor layer thickness over the course of 8 hours [ Time Frame: 8 hours ]
   Influence of circadian rhythm on the length of retinal photoreceptor outer segments
3. En face maps [ Time Frame: 1 day ]
   test an algorithm for production of en face maps of retinal photoreceptor outer segment length

Eligibility Criteria

• Ages Eligible for Study: 18 Years and older (Adult, Older Adult)
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: Yes

Criteria

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

Contacts and Locations

Contacts

Contact: Doreen Schmidl, MD,PhD; 0043140400 ext 29810; doreen.schmidl@meduniwien.ac.at

Locations

Austria

Medical University of Vienna, Department of Clinical Pharmacology; Recruiting

Vienna, Austria, 1090

Contact: Doreen Schmidl, MD, PhD 0043140400 ext 29810 doreen.schmidl@meduniwien.ac.at

Principal Investigator: Doreen Schmidl, MD, PhD

Sub-Investigator: Alina Messner, MD

Sponsors and Collaborators

Medical University of Vienna

Investigators

• Principal Investigator: Doreen Schmidl, MD,PhD; Department of Clinical Pharmacology, Medical University of Vienna

More Information

• Responsible Party: Doreen Schmidl, Associate Professor, MD, PhD, Medical University of Vienna
• ClinicalTrials.gov Identifier: NCT03921931
• Other Study ID Numbers: OPHT-050418
• First Posted: April 19, 2019
• Last Update Posted: February 24, 2021
• Last Verified: February 2021

• Studies a U.S. FDA-regulated Drug Product: No
• Studies a U.S. FDA-regulated Device Product: No

Keywords provided by Doreen Schmidl, Medical University of Vienna:

light stimulation; retinal photoreceptors; light adaptation; functional optical coherence tomography; optophysiology; intrinsic optical signals

Additional relevant MeSH terms:

Macular Degeneration; Glaucoma, Open-Angle; Geographic Atrophy; Glaucoma; Ocular Hypertension; Eye Diseases; Retinal Degeneration; Retinal Diseases