Development of a Portable Objective Method for Assessment of Visual Field Loss

 描述(申请人提供)：青光眼是不可逆转的失明和残疾的主要原因。这种疾病直到晚期仍可保持相对无症状，因此，及早发现和监测功能损害对于预防功能损害和失明至关重要。传统上，检测该病中的功能丧失 使用标准自动视野检查(SAP)。然而，SAP测试受到检查的复杂性、患者反应的主观性、较大的变异性、成本和缺乏的限制 可携带性。该提案的总体目标是解决当前可用的 通过开发一种便携式客观方法来评估青光眼的视野损失。该提案的研究将针对以下3个具体目标：1)开发基于便携式、客观、多焦点稳态(MfSSVEP)的视野评估平台，集成可穿戴式无线干式脑电系统和头盔显示器；2)开发和验证眼电(EOG)引导的方法，以在使用设想的便携式平台进行测试时评估眼睛凝视情况；3)评估设想的平台的重复性，并进行初步研究，评估其检测青光眼患者与健康对照组相比视力丧失的能力。在具体目标1中，我们将开发一个原型便携式设备，将干电极脑电平台与基于手机的头盔显示器集成在一起，用于刺激呈现。我们将类似的技术用于最近开发的脑-计算机接口，具有无线SSVEP数据采集和处理。在我们的初步研究中，我们还显示了使用mfSSVEP评估视野损失的可行性。在本次研究中，将使用先进的信号处理方法来提高高密度记录的mfSSVEP的信噪比。将通过改变测试参数进行探索性研究，直到获得稳定的测试平台。在具体目标2中，我们将在便携式平台上集成EOG方法，以便识别固定损失，并允许从进一步的分析中删除不可靠的mfSSVEP信号。为了确保SSVEP信号与相应的视野位置匹配，适当的眼睛注视是必不可少的。我们将进行实验，以评估过滤不可靠信号的EOG方法是否提高了mfSSVEP检测视野损失的准确性。在具体目标3中，我们将进行验证性研究，评估使用建议的设备获得的测量的重复性，以及其检测青光眼患者视野丧失的准确性。一种经过验证的、便携的、客观的青光眼视野丧失评估方法可能会改善青光眼进展的筛查、诊断和检测，并降低因疾病而导致的功能损害和失明的比率。

 DESCRIPTION (provided by applicant): Glaucoma is a leading cause of irreversible blindness and disability. The disease can remain relatively asymptomatic until late stages and, therefore, early detection and monitoring of functional damage is paramount to prevent functional impairment and blindness. Detection of functional loss in the disease has traditionally been made using standard automated perimetry (SAP). However, SAP testing is limited by the complexity of the examination, subjectivity of patient responses, large variability, cost, and lack of portability. The overall goal of this proposal is to address limitations of currently available techniques by developing a portable objective method for assessment of visual field loss in glaucoma. The investigations of this proposal will address the following 3 specific aims: 1) To develop a portable, objective, multifocal steady state (mfSSVEP)-based visual field assessment platform, integrating a wearable, wireless dry EEG system and a head-mounted display; 2) To develop and validate an Electrooculogram (EOG)-guided method to assess eye- gaze during testing with the envisioned portable platform and 3) To evaluate the reproducibility of the envisioned platform and to conduct preliminary studies evaluating its ability to detect visual fiel loss in patients with glaucoma compared to healthy control subjects. In Specific Aim 1, we will develop a prototype portable device integrating a dry-electrode EEG platform to a cell phone-based head-mounted display for stimulus presentation. We have used similar technology for recent development of brain-computer interfaces, with wireless SSVEP data acquisition and processing. In our preliminary investigation, we have also shown the feasibility of using mfSSVEP for assessment of visual field loss. In the current investigation, advanced signal processing methods will be used to improve signal-to-noise ratio of mfSSVEP from high-density recording. Exploratory studies will be conducted by varying test parameters until a stable testing platform is achieved. In Specific Aim 2, we will integrate an EOG method to the portable plataform, in order to identify fixation losses and allow identification of unreliable mfSSVEP signals to be removed from further analyses. Appropriate eye fixation is essential in order to ensure matching of SSVEP signals to corresponding visual field locations. We will conduct experiments to assess whether the EOG method to filter out unreliable signals improves the accuracy of mfSSVEP to detect visual field losses. In Specific Aim 3, we will conduct validating studies evaluating the reproducibility of measurements obtained with the proposed device, as well as its accuracy for detecting visual field loss in patients with glaucoma. A validated, portable, objective method for assessment of visual field loss in glaucoma may potentially improve screening, diagnosis and detection of glaucoma progression and reduce rates of functional impairment and blindness from the disease.