Authors: Samuel M. Maione, Victoria S. Pelak, Peter Gerhardstein
Introduction
Visual Snow Syndrome (VSS) is a neurological condition in which people constantly see tiny flickering dots across their entire visual field, similar to TV static. Many individuals with VSS also experience tinnitus (ringing in the ears), afterimages, blue-field entoptic phenomena, night-vision difficulties, anxiety, and depersonalization. Despite its significant impact, there has been no reliable tool for patients to report the severity of their symptoms or how much they interfere with daily life.
To address this, the Colorado Visual Snow Survey 2.0 (CVSS) was developed as a patient-reported outcome measure to track VSS symptoms and their impact on daily functioning. The study “Assessment of a Novel Patient-Reported Outcome Measure for Visual Snow Syndrome: The Colorado Visual Snow Survey 2.0” investigated how well the CVSS captures symptoms, differentiates people with VSS from healthy controls, and identifies which symptoms most strongly predict the presence of VSS.
Methods
Participants: 144 people participated, including 66 with VSS (diagnosed by a doctor or self-identified) and 78 healthy controls. Participants with VSS were recruited through the Visual Snow Initiative, and controls were recruited from Binghamton University.
Survey Tool: The CVSS asks about 10 symptoms commonly associated with VSS:
- Visual static
- Afterimages
- Trails
- Blue-field entoptic phenomena
- Floaters
- Night-vision impairment
- Tinnitus
- Depersonalization/derealization
- Anxiety
- Sadness or loss of interest
For each symptom a participant experienced, they rated four things on a scale of 1–5:
- Intensity
- Interference with electronic devices
- Interference with daily environment
- Impact on daily activities
Analysis: Researchers compared VSS and control groups, tested the internal consistency of the survey, and used statistical methods to see which symptoms best predicted VSS.
Results
Clear separation between groups: People with VSS scored significantly higher than controls on nearly all symptom measures (average score 2.27 vs. 0.74).
No difference between diagnosed and self-diagnosed VSS: Both groups reported similar symptoms, suggesting the CVSS captures VSS symptoms reliably regardless of diagnosis.
Internal consistency: Most symptom ratings were reliable, though some symptoms like afterimages and anxiety had very high similarity across questions, suggesting minor redundancy.
Symptoms that best predict VSS:
- Night-vision impairment
- Blue-field entoptic phenomena
- Afterimages
- Tinnitus
Symptom clusters: Statistical analysis identified two main groups of symptoms:
- Visual symptoms: static, afterimages, blue-field entoptic phenomena, night-vision impairment
- Emotional/mental health symptoms: anxiety, sadness, depersonalization/derealization
Mental health findings: People with VSS reported higher rates of depersonalization, anxiety, and sadness compared to controls, highlighting the broader impact of VSS on well-being.
Conclusion
The CVSS 2.0 is a promising tool for assessing the severity and daily impact of VSS. It reliably differentiates people with VSS from healthy individuals and captures both visual and emotional symptoms.
Some symptoms, such as tinnitus and enhanced entoptic phenomena, may be particularly important for diagnosing and understanding VSS. While the survey is highly consistent and useful, some questions may be refined in future versions to reduce redundancy.
Overall, the CVSS could help clinicians, researchers, and patients track symptoms over time and evaluate the effects of potential treatments. Further studies are needed to confirm these findings in larger and more diverse populations.