A Study Protocol for an Open-Label Feasibility Treatment Trial of Visual Snow Syndrome With Transcranial Magnetic Stimulation

Abstract

Background: Visual Snow (VS) syndrome is believed to be due to aberrant central visual processing. Positron Emission Tomography (PET) brain imaging and visual evoked potential studies provide evidence for excessive neuronal activity in the medial temporal lobe, specifically the lingual gyrus, and suggest the VS syndrome is a hyperexcitability syndrome. These data provide the basis for consideration of repetitive transcranial magnetic stimulation (rTMS) as a potential treatment for the VS syndrome.Objective: To publish the study protocol for a pilot study underway at the University of Colorado School of Medicine to investigate the use of rTMS intervention to improve symptoms and visual dysfunction associated with VS. The study aims to determine the adverse events and drop-out rate, evaluate performance of outcome measures, including a novel VS symptom scale, and describe changes in outcomes associated with treatment.Methods and Design: Up to 10 participants meeting criteria for VS syndrome, age 19–65 years, will undergo an open-label intervention consisting of 10 rTMS sessions, occurring 5 days a week over a 2-week period. Participants will complete pre-treatment and post-treatment assessments that include: the Colorado Visual Snow Scale (CVSS), the National Eye Institute Visual Functional Questionnaire—25 (VFQ-25), the General Anxiety Disorder—7 scale (GAD-7), and three psychophysical visual processing tasks.Discussion: Knowledge gained from this pilot study will inform future study planning and provide valuable lessons for future investigation of rTMS for the VS syndrome. An overview of study proceedings thus far demonstrates recruitment challenges associated with the COVID-19 pandemic, and additional challenges that are unique to the VS syndrome and to treatment schedules associated with TMS.Registration: This study has been approved by the Colorado Multiple Institutional Review Board. ClinicalTrials.gov Identifier: NCT04925232.

Differential Diagnosis of Visual Phenomena Associated with Migraine: Spotlight on Aura and Visual Snow Syndrome

“…Patients also report wearing sunglasses to reduce light sensitivity, improvement with healthy sleep and diet habits, and learning how to ignore symptoms [50]. Repetitive transcranial magnetic stimulation (rTMS) as a potential treatment for VSS is in the pipeline; a preliminary study in nine patients showed a potential improvement [80] and an open-label treatment trial is ongoing [81]. A clinical trial using neurofeedback is also currently ongoing, with the idea of teaching patients to downregulate activity in different regions of the visual cortex (NeurofeebackSnow, NCT04902365).…”

Visual Snow Syndrome in Patient with Migraine: Case Report and Literature Review

“…During the treatment, it is important to avoid stress, engage in regular physical activity, and use lenses with blue light filters or tinted glasses to reduce photophobia. In a study by Grande et al, repetitive transcranial magnetic stimulation (rTMS) is shown as a potential treatment for visual snow syndrome [ 70 ]. Cognitive behavioural therapy has a positive effect [ 34 , 69 ].…”

The efficacy of neuro-optometric visual rehabilitation therapy in patients with visual snow syndrome

“…Previous studies document VSS as having a negative impact on patient QOL and mental health ( 1 ). Treatment trials of anti-epileptic, migraine therapies, and acetazolamide on patients with VSS have shown limited to no efficacy with side effects often outweighing benefits ( 9 ). Consequently, people with VSS have difficulties with everyday activities including driving, reading, and using technological devices, causing problems with work, school, and socializing.…”

“…Going out at night, being in bright light areas, and exercising also affect them. According to most patients, their work, study, and social lives are affected ( 9 ). Consistent with previous research, in this study patients reported the same difficulties in their daily life.…”