Assessment of Visual Function With a Portable Brain-computer Interface

Background \& Significance

Assessment of functional loss in glaucoma has been traditionally made with standard automated perimetry (SAP). Despite the significant progress achieved with the development of SAP, assessment of visual field loss still has significant drawbacks. SAP testing is limited by subjectivity of patient responses and high test-retest variability, frequently requiring many tests for effective detection of change over time. Moreover, as these tests are generally conducted in clinic-based settings, limited patient availability and health care resources often result in an insufficient number of tests acquired over time, with delayed diagnosis and detection of disease progression. The requirement for highly trained technicians, cost, complexity, and lack of portability of SAP also preclude its use for screening of visual field loss in underserved populations. Furthermore, current SAP testing as performed in clinical practice frequently results in delayed detection of progression, with potential late initiation/escalation of treatment and irreversible functional damage.

As a part of a funded Phase I project, the nGoggle (nGoggle Inc., San Diego, CA), the first device of its kind, allowed a portable and objective brain-based assessment of visual function deficits in glaucoma. The nGoggle integrates a wearable, wireless, no-prep EEG system and a head-mounted display (HMD) to allow users to routinely monitor electrical brain activities associated with visual field stimulation. A recent study comparing the diagnostic accuracies of an earlier version of the nGoggle and SAP in discriminating patients with glaucoma from healthy subjects found that the nGoggle performed at least as well, if not better than, SAP with the additional advantage of portability and objectivity.

The overall goal of this proposal is to test the nGoggle's accuracy and repeatability in detecting visual function loss. In addition, its ability to stage glaucomatous damage, by discriminating patients at different stages of the disease will be evaluated. Finally, the relationship between nGoggle metrics and neural damage in glaucoma as detected by other objective techniques such as optical coherence tomography will also be investigated. Patients with other diseases affecting the visual system will also be included in order to assess whether the nGoggle can differentiate glaucoma from them.

Study Design \& Procedures

This will be a longitudinal study in which patients will be examined approximately biannually. The following patients will be recruited:

1. Glaucoma;
2. Suspicion of having glaucoma;
3. Non-glaucomatous optic neuropathies;
4. Age-related macular degeneration (AMD);
5. Retinal degenerations;
6. Other diseases involving the visual pathways such as optic neuritis, tumors or ischemic neuropathy.
7. Healthy subjects

General evaluation:

As part of the study all participants will undergo the following general evaluation:

1. Review of medical history;
2. Comprehensive ophthalmologic examination
3. Questionnaires: a. Cognitive function using the Montreal Cognitive Assessment (MoCA); b. A short structured interview to obtain vision-related quality of life information using the National Eye Institute 25-Item Visual Functioning Questionnaire (NEI VFQ-25); c. A questionnaire to assess patient's satisfaction with the nGoggle testing, including easiness of placement, comfort, and user-interface.
4. Electroencephalogram (EEG) and Visual Evoked Potentials (VEP): Visual evoked potentials (VEP) will be evaluated with Diopsys NOVA (Diopsys, Inc.), which is a well-established conventional multifocal VEP device to assess brain functioning following visual stimuli from a computer screen. Subjects will also be monitored with an EEG system integrated with a head-mounted display (nGoggle, Inc.). The nGoggle is a portable visual evoked potential system that uses an EEG to acquire visual evoked potentials in response to visual stimuli presented on a virtual reality goggle.

Risk/Benefit Assessment

Risks:

Risks from participating in the study are very low. The primary risks for all participants are some discomforts, which are similar to those encountered in any complete eye examination. Participants will undergo non-invasive procedures used for diagnostic purposes that are used in standard clinical care. Eventually, it will be necessary to use numbing or dilating drops for fundus examination, as is done in standard clinical care. Some risks of those drops include: dry eye, mild headache, blurred vision, drowsiness, burning eyes, tearing, light sensitivity, redness, and allergy reactions. The only non-FDA approved device used in this study is the nGoggle (nGoggle Inc.), which is an investigational diagnostic device qualified as a non-significant risk device. The subject may experience mild discomfort due to drying of the eye during the study. Should a patient note drying, a drop of artificial tears will be placed over the eye by the study key personnel. In very rare cases, artificial eye tear drops may cause irritation or allergy. There are no known risks associated with the EEG test other than discomfort and fatigue. Subjects might become bored, fatigued or distressed while participating. To minimize these potential effects, the tasks will be kept short and subjects will be instructed that they may request to interrupt the test anytime. All assessments, software, instruments that are not FDA approved will be used as tools to assess disability and device efficacy, and will not be used as a diagnostic procedure without confirmation of the diagnosis by another, medically established diagnostic product or procedure. There is, however, the potential risk of loss of confidentiality. Every effort will be made to keep the information confidential; however, this cannot be guaranteed. Some of the questions that will be asked as part of this study may make the patients feel uncomfortable. Patients may refuse to answer any of the questions and may take a break at any time during the study. Patient may stop their participation in this study at any time.

Unknown/unforeseeable risks

In addition to the risks and discomforts listed here, there may be other risks that are currently not known. Subjects will be informed if any other potential risk becomes known through the duration of the study. Also, the risks and discomforts may occur more often or be more severe than have been seen before and written in this form.

Benefits:

Subjects will be referred from the Duke Eye Center care providers after a comprehensive clinical eye examination from a routine visit. If the last clinical eye examination is not within 6 months of the study visit, the participant will be examined by the PI, with no additional cost to the patient.

Participants will also undergo tests that will allow the validation and development of a transformative device for diagnosing and monitoring ocular diseases, and could be suited for home-based testing of visual function in the future, which could benefit patients with eye diseases.