Real-time Acoustic Biofeedback for Enhancing Fixation Stability: A Proof-of-concept Study to Improve Ophthalmic Imaging Diagnostic Quality
试验速览
- 阶段
- 不适用
- 状态
- Enrolling By Invitation
- 发起方
- 入组人数
- 22
- 试验地点
- 1
- 主要终点
- Fixation stability - change from baseline fixation stability recorded without acoustic fixation device compared to fixation stability recorded with acoustic fixation device
研究概览
简要总结
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.
详细描述
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.
研究设计
- 研究类型
- Interventional
- 分配方式
- Non Randomized
- 干预模型
- Parallel
- 主要目的
- Other
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Healthy participants:
- •minimum age of 18 years
- •no neurological or ophthalmological disease
- •ability to perceive auditory feedback
- •normal vision
- •consent to participate in study
- •minimum age of 18 years
- •existing ophthalmological diagnosis of fixation deficite or loss
- •ability to perceive auditory feedback
- •consent to participate in study
排除标准
- •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
研究组 & 干预措施
Blind participants
Blind participants receive auditory feedback via our acoustic fixation device in three conditions to assess effects on fixation.
干预措施: A device providing acoustic real-time biofeedback (Device)
Healthy participants
Healthy participants receive the same auditory feedback via our acoustic fixation device in three conditions to assess effects on fixation.
干预措施: A device providing acoustic real-time biofeedback (Device)
结局指标
主要结局
Fixation stability - change from baseline fixation stability recorded without acoustic fixation device compared to fixation stability recorded with acoustic fixation device
时间窗: 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).
次要结局
- Change in time to achieve fixation over repeated trials(Day 1)
- Subjective exhaustion rating (Likert scale, 1-10)(Day 1)
- Difference in fixation stability (BCEA, time to fixate in ms) between blind and healthy participants across feedback conditions(Day 1)
- Correlation between pupil diameter change (mm) and fixation stability (BCEA)(Day 1)
- Comparison of fixation stability with clinical and imaging parameters(Day 1)
研究者
Dorothea Laurence, MD
Clincian Scientist, MD
University Medical Center Goettingen