Visual Snow Syndrome Improves With Modulation of Resting-State Functional MRI Connectivity After Mindfulness-Based
Sui H Wong1, Giuseppe Pontillo, Baris Kanber
1Guy's and St Thomas' NHS Foundation Trust (SHW), London, United Kingdom; Department of Neuroinflammation (GP, BK, FP, MY, ID, CAMGW-K, ATT), UCL Queen Square Institute of Neurology, University College London, London, United Kingdom; Moorfields Eye Hospital (SHW, ID, ATT), London, United Kingdom; King's College London (SHW), London, United Kingdom; South London and Maudsley NHS Foundation Trust (JW), London, United Kingdom; Centre for Medical Image Computing (BK, FP), University College London, London, United Kingdom; NIHR Biomedical Research Centre at UCLH and UCL (BK, FP), London, United Kingdom; Department of Brain & Behavioural Sciences (CAMGW-K), University of Pavia, Pavia, Italy; Brain Connectivity Center (CAMGW-K), IRCCS Mondino Foundation, Pavia, Italy; and Department of Clinical and Movement Neurosciences (SHW), UCL Queen Square Institute of Neurology, University College London, London, United Kingdom.
Background:
Visual snow syndrome (VSS) is associated with functional connectivity (FC) dysregulation of visual networks (VNs). We hypothesized that mindfulness-based cognitive therapy, customized for visual symptoms (MBCT-vision), can treat VSS and modulate dysfunctional VNs.
Methods:
An open-label feasibility study for an 8-week MBCT-vision treatment program was conducted. Primary (symptom severity; impact on daily life) and secondary (WHO-5; CORE-10) outcomes at Week 9 and Week 20 were compared with baseline. Secondary MRI outcomes in a subcohort compared resting-state functional and diffusion MRI between baseline and Week 20.
Results:
Twenty-one participants (14 male participants, median 30 years, range 22-56 years) recruited from January 2020 to October 2021. Two (9.5%) dropped out. Self-rated symptom severity (0-10) improved: baseline (median [interquartile range (IQR)] 7 [6-8]) vs Week 9 (5.5 [3-7], P = 0.015) and Week 20 (4 [3-6], P < 0.001), respectively. Self-rated impact of symptoms on daily life (0-10) improved: baseline (6 [5-8]) vs Week 9 (4 [2-5], P = 0.003) and Week 20 (2 [1-3], P < 0.001), respectively. WHO-5 Wellbeing (0-100) improved: baseline (median [IQR] 52 [36-56]) vs Week 9 (median 64 [47-80], P = 0.001) and Week 20 (68 [48-76], P < 0.001), respectively. CORE-10 Distress (0-40) improved: baseline (15 [12-20]) vs Week 9 (12.5 [11-16.5], P = 0.003) and Week 20 (11 [10-14], P = 0.003), respectively. Within-subject fMRI analysis found reductions between baseline and Week 20, within VN-related FC in the i) left lateral occipital cortex (size = 82 mL, familywise error [FWE]-corrected P value = 0.006) and ii) left cerebellar lobules VIIb/VIII (size = 65 mL, FWE-corrected P value = 0.02), and increases within VN-related FC in the precuneus/posterior cingulate cortex (size = 69 mL, cluster-level FWE-corrected P value = 0.02).
Conclusions:
MBCT-vision was a feasible treatment for VSS, improved symptoms and modulated FC of VNs. This study also showed proof-of-concept for intensive mindfulness interventions in the treatment of neurological conditions.
