Research Study

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Brief Summary

Visual Snow Syndrome (VSS) is a neurological condition causing disturbance to vision. In VSS, there is a disruption in the brain networks that involve the visual pathway. There is currently no validated treatment.

We completed a small treatment study, called a feasibility study. Our study showed that MBCT-vision improved VSS and changed brain networks on functional MRI.

We are now recruiting participants in the UK for a larger MBCT-vision study. This larger MBCT-vision study is a Randomised Controlled Trial (RCT). In Randomised Controlled Trials, participants are randomly assigned to one of two groups: Treatment or Control groups.

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Our research study’s hypothesis

We hypothesise that MBCT-vision can improve VSS by changing neural pathways. We propose that MBCT-vision can improve distressing visual symptoms by reducing its intensity, equip participants with skills of psychological resilience and improve coping with residual visual symptoms. This study will help us answer this research question.

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Study Design

Participants will be allocated at random, into the Treatment group or the Control group.

Participants in Treatment group will receive MBCT-vision. Participants in Control group will receive Standard Care, i.e. waiting with no research intervention. After 5 months, people in the Control group will also be offered MBCT-vision.

The study will be conducted from St Thomas' Hospital, of Guy's and St Thomas' NHS Foundation Trust. The MBCT-vision course is delivered online as a group-learning course. Participants will also be requested to attend the Eye Research Department at St Thomas' Hospital a few times during their study involvement. We are recruiting participants in the United Kingdom.

The key outcome is the comparison of the severity of visual symptoms between the two groups. We will also be evaluating other outcomes using questionnaires and focus group interviews. All recruited participants will also be invited to participate in a metabolomics sub-study. This is to measure the changes in blood metabolites. This will help us understand the mechanisms of VSS and MBCT-vision treatment. ID: NCT06018103


What is MBCT-vision?

MBCT-vision is a customised version of the MBCT course. MBCT was developed by Segal, Williams and Teasdale (2002)* to prevent depression. For the treatment of VSS, we customised MBCT by replacing discussions about preventing depression, with discussions relevant to VSS.

The course teaches mindfulness and cognitive skills.

Mindfulness is a way of paying attention to our experience in a gentle and open way. Research studies on mindfulness show that it can change brain networks.

The cognitive skills learnt in MBCT-vision is an approach that looks at how our experiences, thoughts, feelings, and actions all affect one another. And in turn, how making positive changes in one area can affect all the other areas.

The results of an earlier study on MBCT-vision are about to be published in the Journal of Neuro-Ophthalmology.

*Segal, Z. V., Williams, J. M. G., & Teasdale, J. D. (2002). Mindfulness-based cognitive therapy for depression: A new approach to preventing relapse. Guilford Press.
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Study Inclusion & Exclusion Criteria

Study Inclusion Criteria

People with VSS according to the ICHD-3 criteria; previously diagnosed by a Neurologist, Ophthalmologist, or Neuro-Ophthalmologist

Study Exclusion Criteria

Note: This study is examining the outcome of visual symptoms. Therefore, we are not including people who have other co-existing eye conditions that affects their vision.

The study is testing the impact of intensive mindfulness training. Therefore, we are not able to include people who already had mindfulness training or a daily mindfulness practice.

Please see the other exclusion criteria listed below. Please do reach out to the research team if you are unsure, we will be happy to help advise further

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Other Exclusion Criteria

  • Patients with co-morbid conditions affecting vision
  • Patients with a current severe depressive or psychotic episode as determined by a psychologist
  • Patients with severe difficulties in emotional regulation as determined by a psychologist
  • Patients unable to provide informed consent for participation
  • Patients with insufficient understanding of spoken English (due to need to participate in group discussions)
  • Patients who have previously completed MBCT or similar mindfulness interventions
  • Persons aged < 16 or > 80years
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Healthy Controls for Metabolomics Sub-Study

An exploratory sub-study on the change in metabolomics will recruit healthy controls, inclusion criteria:

Healthy Control Inclusion Criteria

  • Family or household member of a similar age (+/- 8years) to a participant with VSS recruited into the MBCT-vision VSS RCT study
  • Person with no symptoms of VSS
  • Person who self-declares as fit and well with no current medical conditions including anxiety or migraine

Healthy Control Exclusion Criteria

  • Person unable to provide informed consent
  • Person with other co-morbid medical or psychological conditions
  • Person aged < 16 or > 80years
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This study has been sponsored by Guy’s and St Thomas’ NHS Foundation Trust (GSTT) and has received National Ethics Committee approval by the North of Scotland 2 Research Ethics Committee.

The MBCT-vision VSS RCT study is funded by the Visual Snow Initiative.

This study has also been possible due to the success of the MBCT-vision feasibility study, which was funded by the following charities: EyeHope, Guy’s and St Thomas’ Trust charity, and Visual Snow Initiative.

We are grateful to the past participants of the MBCT-vision feasibility study who have been part of a Study Advisory group, in advising the design of the MBCT-vision VSS RCT study.

Dr Wong is also grateful to J Kabat-Zinn for inspiration; Segal, Williams and Teasdale for creating MBCT; and Oxford Mindfulness Centre for training as an MBCT teacher.

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