Neuro-Ophthalmology, Visual Snow Syndrome
Conditions
Keywords
neurofeedback, real-time functional magnetic resonance imaging
Brief summary
Visual snow (VS) is a distressing, life-impacting condition with unrelenting and persistent disturbing visual phenomena. Disease onset is usually around age 20 and is characterized by continuous perception of innumerable flickering dots (like a 'broken television'). The disease is often accompanied by comorbidities such as migraine, tinnitus, depression and anxiety. Neuronally, VS patients show cerebral hypermetabolism, resulting in altered neuronal excitability, as well as increased grey matter volume in parts of the visual cortex. For this pilot study, the investigators aim to recruit VS patients. In a double-blind, randomized and placebo-controlled longitudinal experiment, the investigators will use real-time functional magnetic resonance imaging (rtfMRI) neurofeedback to teach patients to downregulate activity in different regions of the visual cortex. The investigators hypothesize that neurofeedback will allow patients to learn to downregulate their abnormal visual cortex activity. Moreover, the investigators predict that a stronger downregulation of activity from the lingual gyrus will correlate with a more pronounced decrease in VS symptoms.
Detailed description
Currently, there is no pharmacological or non-pharmacological treatment available that significantly reduces the high disease burden produced by VS. Thus, there is an unmet need for an appropriate intervention to treat patients with VS. In this study, the investigators will: 1. Test if rtfMRI-based neurofeedback could serve as therapeutic option for patients with VS. Here, the investigators will examine correlations of neurofeedback regulation success with clinical scores 3 after neurofeedback 2. Examine brain function and structure in patients with VS Primary and secondary endpoint/outcome(s) * Primary outcome variable: VS symptom severity before and after rtfMRI, using standardized clinical assessment. * Secondary outcome variables: fMRI and structural MRI, clinical questionnaires (visual function, anxiety, depression, tinnitus, and migraine), parameters from psychophysical data (assessed before and after neurofeedback). * Linear Mixed model analysis will be performed (using clinical and imaging data) to estimate the impact of rtfMRI on clinical progression and brain function/structure.
Interventions
OTHERneurofeedback
(based on real-time functional magnetic resonance signals)
Sponsors
University of Zurich
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Investigator)
Masking description
Double Blind
Intervention model description
In a double-blind, randomized and placebo-controlled longitudinal experiment, the investigators will use real-time functional magnetic resonance imaging (rtfMRI) neurofeedback to teach patients to downregulate activity in different regions of the visual cortex. 50 patients (25 in each arm)
Eligibility
Sex/Gender
ALL
Age
18 Years to 60 Years
Healthy volunteers
Yes
Inclusion criteria
* Patients with VS (≥ 18 to ≤ 60 years), which can read and sign the informed consent form. * Male and female * Healthy controls (≥ 18 to ≤ 60 years), which can read and sign the informed consent form.
Exclusion criteria
* MR
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| symptom severity | Acute after neurofeedback and 3 months after neurofeedback | Changes in symptom severity before and after real-time fMRI neurofeedback |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Magnetic resonance imaging | before and immediately after the neurofeedback sessions | Assessment of Magnetic resonance imaging parameters related to brain function and structure |
Countries
Switzerland
Outcome results
None listed