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

Primary Open-angle Glaucoma Clinical Trial

Official title:

Assessment of Retinal Photoreceptor Outer Segment Length With Optical Coherence Tomography Before and After Light Stimulation - a Pilot Study

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT03921931
• Other study ID #: OPHT-050418
• Status: Recruiting
• Phase: N/A
• Start date: November 26, 2018
• Est. completion date: May 31, 2023

Study information

• Verified date: March 2023
• Source: Medical University of Vienna
• Contact: Doreen Schmidl, MD,PhD
• Phone: 0043140400
• Email: doreen.schmidl[@]meduniwien.ac.at
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial 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.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 35
• Est. completion date: May 31, 2023
• Est. primary completion date: May 31, 2023
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years and older

Eligibility

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

Related Conditions & MeSH terms

• Geographic Atrophy
• Glaucoma, Open-Angle
• Macular Degeneration
• Macular Degeneration, Dry
• Primary Open-angle Glaucoma

Intervention

Other:
• White light stimulation
Stimulation of the retina with white light

Locations

Country	Name	City	State
Austria	Medical University of Vienna, Department of Clinical Pharmacology	Vienna

Sponsors (1)

Lead Sponsor	Collaborator
Medical University of Vienna

Country where clinical trial is conducted

Austria, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Light stimulation	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	1 day
Secondary	Light stimulation of contralateral eye	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	1 day
Secondary	Difference in photoreceptor layer thickness over the course of 8 hours	Influence of circadian rhythm on the length of retinal photoreceptor outer segments	8 hours
Secondary	En face maps	test an algorithm for production of en face maps of retinal photoreceptor outer segment length	1 day