Optic Nerve Diseases

The purpose of this study is to determine the feasibility of producing artificial vision in persons with blindness. Study participants will have wireless electrical stimulators implanted into the cortical vision processing areas of their brains. The ability of the participants to perceive artificial vision in response to electrical stimulation will be assessed.

Giant cell arteritis (GCA) is an inflammatory disease of large and medium arteries that can cause irreversible vision loss. Glucocorticoids (GCs) rapidly suppress inflammation, but diagnostic imaging tests such as temporal artery ultrasound or biopsy often become falsely negative within days of treatment. The optic nerve sheath diameter (ONSD), measurable by ocular ultrasound, reflects perineural edema and may serve as a quantitative biomarker of ocular inflammation in GCA. The SONIC-TIME study (Early Temporal Dynamics of Optic Nerve Sheath Diameter After Glucocorticoid Therapy in Giant Cell Arteritis) is a single-center, prospective observational substudy embedded within SONIC-GCA (NCT05749094) at Hôpital du Sacré-Cœur de Montréal. It aims to characterize how rapidly ONSD decreases after GC initiation and how this trajectory relates to cumulative GC exposure, intravenous methylprednisolone, and early use of steroid-sparing therapies. Sixty participants with newly diagnosed GCA will undergo serial optic nerve sheath ultrasound, blood tests (CRP, ESR), and when feasible, temporal artery ultrasound over the first two months of therapy (Days 3, 7, 10, 14, 21, 28, and Month 2). No experimental treatments are given; all participants receive standard-of-care therapy. The primary objective is to quantify the percent change in mean ONSD from baseline to Day 28. Secondary objectives include modeling ONSD change over time, assessing associations with cumulative steroid dose and inflammatory markers, and estimating the time to normalization below the SONIC-GCA cutoff. Findings will define the optimal imaging window and refine the diagnostic and monitoring role of optic nerve ultrasound in GCA.

The goal of the current study is to conduct a pilot study to test a new version of the handheld OCT device capable of auto-alignment to image the retina in adult volunteers, and adult and pediatric patients in clinic.

Handheld optical coherence tomography (OCT) has become an important imaging modality to evaluate the pediatric retina. The objective of this pilot study is to compare a new contact OCT system (Theia Imaging) with an investigational noncontact OCT system (Duke Biomedical Engineering) to assess their ability to image the pediatric retina. The investigators hypothesize that the contact OCT system is superior in imaging larger areas of the retina (larger field-of-view), while it has similar resolution to image the retina substructures (non-inferior image quality).

The overall aim of this study is to see whether long-term electrical stimulation with a home-stimulation device works well and is safe for the treatment of open-angle glaucoma. Open-Angle Glaucoma is a disease where the nerves in the back of your eye die off faster than expected regardless of your eye pressure.