Overview

The purpose of this study is to test the efficacy and feasibility of an intervention protocol for home-based repetitive transorbital alternating current stimulation (rtACS) for the treatment of visual impairment in people with optic neuropathy. The primary aims are to evaluate the effectiveness of home-based rtACS to ameliorate the progressive effects of vision loss functionally in the eye and the visual pathway, and in regard to people's independence (i.e., functional ability).

Eligibility

Inclusion Criteria:

1. Age equal to or over 18 years old
2. Must have a permanent residence
3. Diagnosis of optic neuropathy
4. VF defects present in at least one eye (MD ≤ -3.00 dB) FL, FP, FN <33%
5. Visual Field Index (VFI) 10-90%
6. Clear optical apparatus
7. Best-corrected VA of 20/400 or better in at least one eye
8. Commitment to comply with study procedures: 8-week period of intervention sessions (30 sessions every other day), baseline visit, post-intervention visit, and 2 follow-up visits (2 days per visit).
   1. Scheduling
   2. Testing
9. A subject deemed incapable of performing the study intervention independently due to

   visual impairment or any other condition that may prevent them from performing the intervention accurately require a family member or caregiver to assist in performing the intervention.

Exclusion Criteria:

1. High intraocular pressure (over 27 mmHg)
2. End-stage organ disease or medical condition with subsequent vision loss (e.g., diabetes, stroke)
3. Advanced or unstable retinal diseases
4. Pathological nystagmus
5. Acute conjunctivitis
6. Photosensitivity to flickering lights
7. Non-ocular/ocular surgery within the previous 2 months to enrollment date
8. Electric or electronic implants (e.g., cardiac pacemaker)
9. Metallic artifacts/implants in head and/or torso (titanium screw and dental implants are allowed)
10. Diagnosed epilepsy on medical treatment
11. Auto-immune disease, acute stage (e.g., rheumatoid arthritis)
12. Metastatic disease
13. Certain mental diseases/psychiatric conditions (e.g., schizophrenia) that would affect the subject's ability to perform all necessary study tasks
14. Any chronic unstable medical conditions (e.g., uncontrolled diabetes,) that may cause a subject to miss one or more of the interventions and visits
15. Addiction (e.g., drug/alcohol dependence) that has not been in abstinent control for at least one year
16. Uncontrolled systemic hypertension (historical BP > 160/100 mmHg)
17. Pregnant or breast-feeding women or women that are planning to become pregnant, as this device has not been tested on pregnant women and there is no data on using rtACS for this particular group
18. Any severe skin condition (e.g., blisters, open wounds, cuts or irritation) or other skin defect which compromise the integrity of the skin at or near stimulation locations
19. IOP that the principal investigator determines that is not clinically stable
20. Complete blindness of both eyes
21. Non-resected brain tumors
22. Unstable diabetic retinopathy in the study eye
23. Optic neuropathies secondary to brain tumors
24. Subjects without the capacity to consent