Retinal DystrophiesNCT07529041
Real-time Acoustic Biofeedback for Enhancing Fixation Stability: A Proof-of-concept Study to Improve Ophthalmic Imaging Diagnostic Quality
A study testing A device providing acoustic real-time biofeedback in people with Retinal Dystrophies and Geographic Atrophy, run by University Medical Center Goettingen at 1 site in Germany.
Trial summary
The goal of this Proof of Concept Feasibility Study is to improve the fixation stability in patients with fixation loss due to blindness or central vision loss using a patented acoustic real-time feedback device. The main questions it aims to answer are: 1. Read more about this study
- Who is it for?
- Ages 18 years and olderHealthy volunteers can take part
- Conditions the study is for
- Retinal Dystrophies, Geographic Atrophy, Blindness
- What is being tested?
- A device providing acoustic real-time biofeedback
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 22 participants
- Where
- 1 siteGermany
- Study dates
- 27 Aug 2025to 15 May 2026
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- Healthy participants:
- minimum age of 18 years
- no neurological or ophthalmological disease
- ability to perceive auditory feedback
- normal vision
- consent to participate in study
Show all 11Show fewer
- Patients:
- minimum age of 18 years
- existing ophthalmological diagnosis of fixation deficite or loss
- ability to perceive auditory feedback
- consent to participate in study
Who cannot join
- lack of ability to consent to participate in study
- reduced cooperation during examination or recording
- inability to perceive auditory feedback
- age below 18 years
- patients with nystagmus or inability to move eyes
- opacity of cornea or other ocular structures preventing successful eye tracking
- inability to communicate
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Germany1 site
EKFZ Else Kroener Fresenius Center for Optogenetic Therapies, University Medical Center Goettingen
Göttingen, 37075
About this study
The goal of this Proof of Concept Feasibility Study is to improve the fixation stability in patients with fixation loss due to blindness or central vision loss using a patented acoustic real-time feedback device. The main questions it aims to answer are:
- Fixation guidance - can real-time acoustic biofeedback improve the fixation in healthy patients as well as patients with fixation loss?
- Optimization of fixation guidance - testing of different stimuli to optimize an acoustic training protocol.
- Optimization of imaging acquisition - testing improvement of both imaging quality and acquisition time using the acoustic feedback tool.
Read more
For the proof-of-concept-study, patients are asked to fixate on a target point in a darkened room and keep up the fixation. We record patients eye movements with near-infrared-lighting and a camera. Fixation is tested in three conditions - visual target only, auditory feedback only, and visual target followed by auditory feedback. In between each set of trials, patients are asked to rate their subjective exhaustion on a Likert scale. At the end of each recording session, patients are handed a questionnaire for feedback on our proof-of-concept study and device settings.
An ethics-approved extension phase is planned to further optimize device parameters and assess performance in a clinical setting.
Read the detailed description
The goal of this Proof of Concept Feasibility Study is to improve the fixation stability in patients with fixation loss due to blindness or central vision loss using a patented acoustic real-time feedback device. The main questions it aims to answer are:
- Fixation guidance - can real-time acoustic biofeedback improve the fixation in healthy patients as well as patients with fixation loss?
- Optimization of fixation guidance - testing of different stimuli to optimize an acoustic training protocol.
- Optimization of imaging acquisition - testing improvement of both imaging quality and acquisition time using the acoustic feedback tool.
Primary endpoints: Fixation stability (in BCEA and distance from target center), fixation duration, time to fixate. We test fixation in two angles: neutral position (0°) and at 15° eccentricity. We compare three conditions: visual target only, combined visual and auditory feedback, and auditory feedback only.
Secondary endpoints: adaptation and training effects over time, exhaustion measured in a Likert scale. We measure changes of pupil diameter in response to acoustic and visual stimuli. We also compare efficacy between healthy subjects and subjects with fixation loss and compare efficacy between the three conditions.
For the proof-of-concept part of our study, patients are asked to fixate on a target point in a darkened room and keep up fixation for 10 seconds. We record patients eye movements with near-infrared-lighting and a camera. There are three blocks for each condition (visual, auditory, combined), each block consists of 10 trials per eye and per angle. In between each set of trials, patients are asked to rate their subjective exhaustion on a Likert scale. At the end of each recording session, we ask patients for their subjective feedback on which condition was easiest to keep up fixation, whether auditory stimuli were sufficient and open-ended questions on potential improvements of the setup.
An ethics-approved extension phase is planned to further optimize device parameters and assess performance in a clinical setting. We validate the findings of our proof-of-concept study and optimize the device settings by adding the acoustic fixation device to our imaging devices. We will compare the results to answer the question whether the acoustic fixation device will lead to an improved imaging quality and acquisition time.
- Conditions
- Retinal Dystrophies, Geographic Atrophy, Blindness
- Being tested
- A device providing acoustic real-time biofeedback
- Medical subject headings
- Retinal Dystrophies, Geographic Atrophy, Blindness
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
A device providing acoustic real-time biofeedbackDevice
Also called eyeFAST - eye Fixation by Acoustic Stabilization & Tracking
We use a camera and an eye tracking software, linked with our spatial-audio mapping tool. Participants receive real-time audio feedback on the location of their gaze. Negative feedback sounds are encoded to convey distance and direction of the deviation from the center. When the patients fixate on the target area, they receive a positive feedback sound.
| Study group | Role | What they receive |
|---|---|---|
| Blind participants | Experimental | Blind participants receive auditory feedback via our acoustic fixation device in three conditions to assess effects on fixation. Receives: Device: A device providing acoustic real-time biofeedback |
| Healthy participants | Experimental | Healthy participants receive the same auditory feedback via our acoustic fixation device in three conditions to assess effects on fixation. Receives: Device: A device providing acoustic real-time biofeedback |
What is being measured
The primary outcome is the main question the study is designed to answer.
Fixation stability - change from baseline fixation stability recorded without acoustic fixation device compared to fixation stability recorded with acoustic fixation device
In Phase A, we analyse the fixation stability as the distance from the target center (Median [IQR]), duration of fixation and time to achieve stable fixation (latency). We also use posthoc video analysis to generate the BCEA as a measure of fixation stability in each condition and each angle (0 and 15 degrees).
Measured: Day 1
Secondary outcomes (5)
Change in time to achieve fixation over repeated trials
Time required to achieve fixation was assessed across repeated trials to evaluate potential training or adaptation effects. We calculate the time to achieve fixation in seconds across 10 trials per eye per condition per angle. We compare the time to fixate in milliseconds of the first half of trials to the second half of trials.
Measured: Day 1
Subjective exhaustion rating (Likert scale, 1-10)
We test the subjective exhaustion of each participant after each recording session. We provide a scale from 1-10 (1 being extremely exhausted, 10 being not exhausted at all) for participants to provide subjecte exhaustion feedback.
Measured: Day 1
Difference in fixation stability (BCEA, time to fixate in ms) between blind and healthy participants across feedback conditions
We compare the efficacy of auditory feedback on fixation stabilty between the healthy and the patient subject group. We also compare the efficacy of the three modalities (combined, auditory and visual) in between groups and within each arm to assess the effect of auditory feedback.
Measured: Day 1
Correlation between pupil diameter change (mm) and fixation stability (BCEA)
Further, we measure the pupil reaction as changes in pupil diameter (mm) over time (seconds) across different feedback conditions (visual, auditory, combined) and correlate those changes with the achieved fixation stability parameter (BCEA).
Measured: Day 1
Comparison of fixation stability with clinical and imaging parameters
We further analyse the correlation between achieved fixation stability and clinical parameters (such as visual acuity, age of disease onset, year of diagnosis, clinical and genetic diagnosis) and imaging parameters (presence of EZ in OCT-Scans, thickness of retinal layers, perfusion density, vascular density of deep, intermediate and superficial retinal vascular plexuses in OCTA), fundus autofluorescence, visual field parameters and ophthalmological examination results.
Measured: Day 1
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted14 Apr 2026
- Study start27 Aug 2025
- Primary completion15 Apr 2026 (estimated)
- Study completion15 May 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Retinal DystrophiesStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Other
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Model description
- Participants are assigned to one of two groups (blind patients or healthy subjects). Each participant undergoes a single-session assessment in which multiple device conditions are tested within-subject. The study used a mixed-design with one between-subject factor (group: blind vs. healthy participants) and one within-subject factor (condition visual, auditory, combined). Phase A: proof of concept study (22 participants) Phase B: device optimization (11 blind participants of Phase A)
- Masking
- None (open label)
- Enrolment
- 22 participants (estimated)
Sponsor and investigators
- Lead sponsor
- University Medical Center Goettingen
- Sponsor type
- University, hospital or other
- Collaborators
- Else Kröner Fresenius Foundation
- Responsible party
- Principal investigator, Dorothea Laurence, MD, University Medical Center Goettingen
- Investigators
- Dorothea S Laurence, MD, Principal investigator, University Medical Center Goettingen
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07529041
- Sponsor's protocol ID
- 17/5/25
- Status last verified
- Apr 2026
- First submitted
- 24 Mar 2026
- Last updated
- 14 Apr 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 14 Apr 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Real-time Acoustic Biofeedback for Enhancing Fixation Stability: A Proof-of-concept Study to Improve Ophthalmic Imaging Diagnostic Quality
- ClinicalTrials.gov ID
- NCT07529041
- Acronym / sponsor ID
- 17/5/25
- Conditions
- Retinal Dystrophies, Geographic Atrophy, Blindness
- Study type
- Interventional
- Recruitment status
- Enrolling by invitation
- Enrolment
- 22 participants (estimated)
- Lead sponsor
- University Medical Center GoettingenUniversity, hospital or other
- Collaborators
- Else Kröner Fresenius Foundation
- Study start
- 27 Aug 2025 (actual)
- Primary completion
- 15 Apr 2026 (estimated)
- Study completion
- 15 May 2026 (estimated)
- First posted
- 14 Apr 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The goal of this Proof of Concept Feasibility Study is to improve the fixation stability in patients with fixation loss due to blindness or central vision loss using a patented acoustic real-time feedback device. The main questions it aims to answer are:
- Fixation guidance - can real-time acoustic biofeedback improve the fixation in healthy patients as well as patients with fixation loss?
- Optimization of fixation guidance - testing of different stimuli to optimize an acoustic training protocol.
- Optimization of imaging acquisition - testing improvement of both imaging quality and acquisition time using the acoustic feedback tool.
For the proof-of-concept-study, patients are asked to fixate on a target point in a darkened room and keep up the fixation. We record patients eye movements with near-infrared-lighting and a camera. Fixation is tested in three conditions - visual target only, auditory feedback only, and visual target followed by auditory feedback. In between each set of trials, patients are asked to rate their subjective exhaustion on a Likert scale. At the end of each recording session, patients are handed a questionnaire for feedback on our proof-of-concept study and device settings.
An ethics-approved extension phase is planned to further optimize device parameters and assess performance in a clinical setting.
Detailed description
The goal of this Proof of Concept Feasibility Study is to improve the fixation stability in patients with fixation loss due to blindness or central vision loss using a patented acoustic real-time feedback device. The main questions it aims to answer are:
- Fixation guidance - can real-time acoustic biofeedback improve the fixation in healthy patients as well as patients with fixation loss?
- Optimization of fixation guidance - testing of different stimuli to optimize an acoustic training protocol.
- Optimization of imaging acquisition - testing improvement of both imaging quality and acquisition time using the acoustic feedback tool.
Primary endpoints: Fixation stability (in BCEA and distance from target center), fixation duration, time to fixate. We test fixation in two angles: neutral position (0°) and at 15° eccentricity. We compare three conditions: visual target only, combined visual and auditory feedback, and auditory feedback only.
Secondary endpoints: adaptation and training effects over time, exhaustion measured in a Likert scale. We measure changes of pupil diameter in response to acoustic and visual stimuli. We also compare efficacy between healthy subjects and subjects with fixation loss and compare efficacy between the three conditions.
For the proof-of-concept part of our study, patients are asked to fixate on a target point in a darkened room and keep up fixation for 10 seconds. We record patients eye movements with near-infrared-lighting and a camera. There are three blocks for each condition (visual, auditory, combined), each block consists of 10 trials per eye and per angle. In between each set of trials, patients are asked to rate their subjective exhaustion on a Likert scale. At the end of each recording session, we ask patients for their subjective feedback on which condition was easiest to keep up fixation, whether auditory stimuli were sufficient and open-ended questions on potential improvements of the setup.
An ethics-approved extension phase is planned to further optimize device parameters and assess performance in a clinical setting. We validate the findings of our proof-of-concept study and optimize the device settings by adding the acoustic fixation device to our imaging devices. We will compare the results to answer the question whether the acoustic fixation device will lead to an improved imaging quality and acquisition time.
Study design
- Primary purpose
- Other
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
- Model description
- Participants are assigned to one of two groups (blind patients or healthy subjects). Each participant undergoes a single-session assessment in which multiple device conditions are tested within-subject. The study used a mixed-design with one between-subject factor (group: blind vs. healthy participants) and one within-subject factor (condition visual, auditory, combined). Phase A: proof of concept study (22 participants) Phase B: device optimization (11 blind participants of Phase A)
| Arm | Type | Receives |
|---|---|---|
| Blind participants | Experimental | Device: A device providing acoustic real-time biofeedbackBlind participants receive auditory feedback via our acoustic fixation device in three conditions to assess effects on fixation. |
| Healthy participants | Experimental | Device: A device providing acoustic real-time biofeedbackHealthy participants receive the same auditory feedback via our acoustic fixation device in three conditions to assess effects on fixation. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (11 listed)
- minimum age of 18 years
- no neurological or ophthalmological disease
- ability to perceive auditory feedback
- normal vision
- consent to participate in study
Key exclusion criteria (7 listed)
- lack of ability to consent to participate in study
- reduced cooperation during examination or recording
- inability to perceive auditory feedback
- age below 18 years
- patients with nystagmus or inability to move eyes
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| A device providing acoustic real-time biofeedbackAlso: eyeFAST - eye Fixation by Acoustic Stabilization & TrackingWe use a camera and an eye tracking software, linked with our spatial-audio mapping tool. Participants receive real-time audio feedback on the location of their gaze. Negative feedback sounds are encoded to convey distance and direction of the deviation from the center. When the patients fixate on the target area, they receive a positive feedback sound. | Device | Blind participants, Healthy participants |
Primary outcome
Fixation stability - change from baseline fixation stability recorded without acoustic fixation device compared to fixation stability recorded with acoustic fixation device
Time frame: Day 1
In Phase A, we analyse the fixation stability as the distance from the target center (Median [IQR]), duration of fixation and time to achieve stable fixation (latency). We also use posthoc video analysis to generate the BCEA as a measure of fixation stability in each condition and each angle (0 and 15 degrees).
5 secondary outcomes
Change in time to achieve fixation over repeated trials
Time frame: Day 1
Subjective exhaustion rating (Likert scale, 1-10)
Time frame: Day 1
Difference in fixation stability (BCEA, time to fixate in ms) between blind and healthy participants across feedback conditions
Time frame: Day 1
Correlation between pupil diameter change (mm) and fixation stability (BCEA)
Time frame: Day 1
Comparison of fixation stability with clinical and imaging parameters
Time frame: Day 1
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 14 Apr 2026.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Dorothea S Laurence, MD principal investigator
University Medical Center Goettingen
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing A device providing acoustic real-time biofeedback in people with Retinal Dystrophies and Geographic Atrophy, run by University Medical Center Goettingen at 1 site in Germany.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 11 inclusion and 7 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: enrolling by invitation, as of the sponsor's last update on 14 Apr 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Germany. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Fixation stability - change from baseline fixation stability recorded without acoustic fixation device compared to fixation stability recorded with acoustic fixation device (time frame: Day 1). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 14 Apr 2026.