Visual Snow SyndromeNCT05569733
Simultaneous Fluorodeoxyglucose Positron Emission Tomography (PET) and Magnetic Resonance (MR) in Visual Snow Syndrome
An observational study of Visual Snow Syndrome, run by Universitaire Ziekenhuizen KU Leuven.
Trial summary
Visual snow syndrome (VSS) is a neurologic condition where patients experience tiny flickering dots in their entire visual field. It has been reported that the brain consumes more glucose in the lingual gyrus (a subdivision of the occipital cortex) and that this also shows increased volume of grey matter (neurons and… Read more about this study
- Who is it for?
- Ages 18 to 85 yearsHealthy volunteers can take part
- Conditions the study is for
- Visual Snow Syndrome
- What is being tested?
- simultaneous fluor-18 fluorodeoxyglucose (FDG) positron emission tomography with magnetic resonance imaging (PET/MRI)
- Type of treatment
- Injection or infusion
- How many people
- 22 participants
- Where
- No sites listed yet
- Study dates
- 2 Jan 2017to 1 Feb 2022
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 85 years
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Study population: Group 1 : Visual Snow Syndrome patients Group 2 : Healthy Controls
Who may be able to join
- M/F, age 18-85,
- diagnosis of VSS by an experienced neurologist : dynamic, continuous, black and white tiny dots in the entire visual field lasting longer than 3 months, with at least two additional visual symptoms
- age 18-85 years, M/F, in general healthy condition
- normal neurological examination, Mini-Mental State Examination (MMSE) ≥ 28, Beck's Depression Inventory (BDI) score ≤ 9, and a normal structural volumetric MRI.
Who cannot join
- other underlying neurological conditions inclusive ophthalmological examinations
- GROUP 2 : Controls
- history of major internal pathology, neurological and/or psychiatric disorders (including psychosis, depression, and anxiety),
- history of frequent migraine attacks, substance abuse or current use of any central acting medication
- first-degree relatives with dementia.
About this study
Official title: Simultaneous Fluorodeoxyglucose and Magnetic Resonance Imaging (18F-FDG PET/MR) Study of Metabolic and Structural Changes in Visual Snow Syndrome Compared to Healthy Controls
Visual snow syndrome (VSS) is a neurologic condition where patients experience tiny flickering dots in their entire visual field. It has been reported that the brain consumes more glucose in the lingual gyrus (a subdivision of the occipital cortex) and that this also shows increased volume of grey matter (neurons and supporting cells). In this study, the investigators apply fluor-18 fluorodeoxyglucose positron emission tomography with magnetic resonance imaging (18F-FDG PET/MR) in patients with VSS and compare this to healthy controls. Aside from an analysis in each brain volume element (voxel), the accuracy of classifying groups based on a volume-of-interest (VOI) analysis of both PET and MR is studied, Lastly, this is also compared to a visual assessment of the PET and MR images.
Read the detailed description
Aim : Prospective measurement of brain glucose metabolism and structural integrity in the brain of subjects with visual snow syndrome (VSS). Voxel-based and volume-of interest comparison to age matched healthy controls retrospectively obtained on the same simultaneous PET/MR imaging system.
Hypothesis : 1/ VSS patients show overactivation of parts of the visual system, in particular the lingual gyrus, which is likely related to larger volume of the gyrus on structural imaging. 2/ Discrimination of VSS patients versus controls can be done by visual read of FDG PET and/or volume-of-interest based discriminant analysis.
Methods : Recruitment through neurology practice specialised in VSS, detailed history taking and assessment of in/exclusion criteria, scanning with simultaneous18F-FDG PET/MR Signa GE Healthcare.
Analysis : visual assessment, group-based voxel and volume-of-interest based analysis (FDG PET, volumetry T1 MRI) with appropriate statistics and corrections for multiple regional comparisons. Discriminant analysis on VOI based data. Dual observer scoring of visual data and assessment of accuracy, sensitivity and specificity of visual image analysis compared to clinical final diagnosis.
- Conditions
- Visual Snow Syndrome
- Being tested
- simultaneous fluor-18 fluorodeoxyglucose (FDG) positron emission tomography with magnetic resonance imaging (PET/MRI)
- Keywords
- FDG PET, PET/MR, volumetry, visual analysis, discriminant analysis
- Medical subject headings
- visual snow syndrome
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
simultaneous fluor-18 fluorodeoxyglucose (FDG) positron emission tomography with magnetic resonance imaging (PET/MRI)Diagnostic test
All subjects fast at least for 4 hours prior to 18F-FDG injection. 18F-FDG is injected intravenously (150 megabecquerel (MBq)) in standard ambient conditions, supine in a dark, noise free room with eyes and ears open. 18F-FDG PET images are acquired for 20 min on a simultaneous GE Signa 3 Tesla (3T) PET/MR scanner with integrated Time-of-Flight (TOF) (GE Healthcare, Chicago, USA). Simultaneous with the 18F-FDG PET/MR acquisition, zero-echo-time (ZTE) MR data are acquired for attenuation correction and a 3D volumetric T1-weighted BRAVO MR sequence using a vendor supplied high-resolution 8-channel phased array head coil (GE Healthcare, Milwaukee, USA).
| Study group | Role | What they receive |
|---|---|---|
| VSS | Patients with visual snow syndrome Receives: Diagnostic Test: simultaneous fluor-18 fluorodeoxyglucose (FDG) positron emission tomography with magnetic resonance imaging (PET/MRI) | |
| controls | healthy, screened age-matched controls Receives: Diagnostic Test: simultaneous fluor-18 fluorodeoxyglucose (FDG) positron emission tomography with magnetic resonance imaging (PET/MRI) |
What is being measured
The primary outcome is the main question the study is designed to answer.
Group difference in regional brain metabolism as assessed with 18F-FDG positron emission tomography
Visual, voxel- and volume-of-interest based assessment of of FDG PET
Measured: analysis done immediately after imaging
Group difference in regional brain volume assessed with volumetric magnetic resonance imaging.
Visual, voxel- and volume-of-interest based assessment of MRI images
Measured: at baseline
Secondary outcomes (4)
Discriminant analysis of PET metabolic differences
Statistical discriminant analysis of FDG between VSS patients and controls
Measured: at baseline
Visual scoring of PET metabolic differences
Visual scoring of FDG between VSS patients and controls
Measured: at baseline
Discriminant analysis of MR volumetric differences
Statistical discriminant analysis of regional MR volumetry between VSS patients and controls
Measured: at baseline
Visual scoring of MR volumetric differences
Visual scoring of regional MR volumetry between VSS patients and controls
Measured: at baseline
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted6 Oct 2022
- Study start2 Jan 2017
- Primary completion2 Sep 2017
- Study completion1 Feb 2022
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Visual Snow SyndromeStudies of the same condition, open and under way.
- More trials run by Universitaire Ziekenhuizen KU LeuvenThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 22 participants (actual)
Sponsor and investigators
- Lead sponsor
- Universitaire Ziekenhuizen KU Leuven
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Koen Van Laere, MD PhD, Principal investigator, Head Nuclear Medicine, University Hospitals Leuven
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05569733
- Sponsor's protocol ID
- S58764-S58571
- Status last verified
- Sep 2022
- First submitted
- 27 Sep 2022
- Last updated
- 27 Jan 2023
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: Data can be shared on a reasonable request, including full FDG PET and MRI data as well as supporting information.
Publications
Van Laere K, Ceccarini J, Gebruers J, Goffin K, Boon E. Simultaneous 18F-FDG PET/MR metabolic and structural changes in visual snow syndrome and diagnostic use. EJNMMI Res. 2022 Dec 30;12(1):77. doi: 10.1186/s13550-022-00949-0.
PubMed 36583806
Study at a glance
From the registry record, last updated by the sponsor on 27 Jan 2023. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Simultaneous Fluorodeoxyglucose and Magnetic Resonance Imaging (18F-FDG PET/MR) Study of Metabolic and Structural Changes in Visual Snow Syndrome Compared to Healthy Controls
- ClinicalTrials.gov ID
- NCT05569733
- Acronym / sponsor ID
- S58764-S58571
- Conditions
- Visual Snow Syndrome
- Keywords
- FDG PET, PET/MR, volumetry, visual analysis, discriminant analysis
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 22 participants (actual)
- Lead sponsor
- Universitaire Ziekenhuizen KU LeuvenUniversity, hospital or other
- Study start
- 2 Jan 2017 (actual)
- Primary completion
- 2 Sep 2017 (actual)
- Study completion
- 1 Feb 2022 (actual)
- First posted
- 6 Oct 2022 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Visual snow syndrome (VSS) is a neurologic condition where patients experience tiny flickering dots in their entire visual field. It has been reported that the brain consumes more glucose in the lingual gyrus (a subdivision of the occipital cortex) and that this also shows increased volume of grey matter (neurons and supporting cells). In this study, the investigators apply fluor-18 fluorodeoxyglucose positron emission tomography with magnetic resonance imaging (18F-FDG PET/MR) in patients with VSS and compare this to healthy controls. Aside from an analysis in each brain volume element (voxel), the accuracy of classifying groups based on a volume-of-interest (VOI) analysis of both PET and MR is studied, Lastly, this is also compared to a visual assessment of the PET and MR images.
Detailed description
Aim : Prospective measurement of brain glucose metabolism and structural integrity in the brain of subjects with visual snow syndrome (VSS). Voxel-based and volume-of interest comparison to age matched healthy controls retrospectively obtained on the same simultaneous PET/MR imaging system.
Hypothesis : 1/ VSS patients show overactivation of parts of the visual system, in particular the lingual gyrus, which is likely related to larger volume of the gyrus on structural imaging. 2/ Discrimination of VSS patients versus controls can be done by visual read of FDG PET and/or volume-of-interest based discriminant analysis.
Methods : Recruitment through neurology practice specialised in VSS, detailed history taking and assessment of in/exclusion criteria, scanning with simultaneous18F-FDG PET/MR Signa GE Healthcare.
Analysis : visual assessment, group-based voxel and volume-of-interest based analysis (FDG PET, volumetry T1 MRI) with appropriate statistics and corrections for multiple regional comparisons. Discriminant analysis on VOI based data. Dual observer scoring of visual data and assessment of accuracy, sensitivity and specificity of visual image analysis compared to clinical final diagnosis.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| VSS | – | Diagnostic Test: simultaneous fluor-18 fluorodeoxyglucose (FDG) positron emission tomography with magnetic resonance imaging (PET/MRI)Patients with visual snow syndrome |
| controls | – | Diagnostic Test: simultaneous fluor-18 fluorodeoxyglucose (FDG) positron emission tomography with magnetic resonance imaging (PET/MRI)healthy, screened age-matched controls |
Who may qualify
- Ages
- 18 to 85 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
- Study population
- Group 1 : Visual Snow Syndrome patients Group 2 : Healthy Controls
Key inclusion criteria (4 listed)
- M/F, age 18-85,
- diagnosis of VSS by an experienced neurologist : dynamic, continuous, black and white tiny dots in the entire visual field lasting longer than 3 months, with at least two additional visual symptoms
- age 18-85 years, M/F, in general healthy condition
- normal neurological examination, Mini-Mental State Examination (MMSE) ≥ 28, Beck's Depression Inventory (BDI) score ≤ 9, and a normal structural volumetric MRI.
Key exclusion criteria (5 listed)
- other underlying neurological conditions inclusive ophthalmological examinations
- GROUP 2 : Controls
- history of major internal pathology, neurological and/or psychiatric disorders (including psychosis, depression, and anxiety),
- history of frequent migraine attacks, substance abuse or current use of any central acting medication
- first-degree relatives with dementia.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| simultaneous fluor-18 fluorodeoxyglucose (FDG) positron emission tomography with magnetic resonance imaging (PET/MRI)All subjects fast at least for 4 hours prior to 18F-FDG injection. 18F-FDG is injected intravenously (150 megabecquerel (MBq)) in standard ambient conditions, supine in a dark, noise free room with eyes and ears open. 18F-FDG PET images are acquired for 20 min on a simultaneous GE Signa 3 Tesla (3T) PET/MR scanner with integrated Time-of-Flight (TOF) (GE Healthcare, Chicago, USA). Simultaneous with the 18F-FDG PET/MR acquisition, zero-echo-time (ZTE) MR data are acquired for attenuation correction and a 3D volumetric T1-weighted BRAVO MR sequence using a vendor supplied high-resolution 8-channel phased array head coil (GE Healthcare, Milwaukee, USA). | Diagnostic test | VSS, controls |
Primary outcome
Group difference in regional brain metabolism as assessed with 18F-FDG positron emission tomography
Time frame: analysis done immediately after imaging
Visual, voxel- and volume-of-interest based assessment of of FDG PET
Group difference in regional brain volume assessed with volumetric magnetic resonance imaging.
Time frame: at baseline
Visual, voxel- and volume-of-interest based assessment of MRI images
4 secondary outcomes
Discriminant analysis of PET metabolic differences
Time frame: at baseline
Visual scoring of PET metabolic differences
Time frame: at baseline
Discriminant analysis of MR volumetric differences
Time frame: at baseline
Visual scoring of MR volumetric differences
Time frame: at baseline
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 27 Jan 2023.
- Derived from this study: PubMed 36583806Van Laere K, Ceccarini J, Gebruers J, Goffin K, Boon E. Simultaneous 18F-FDG PET/MR metabolic and structural changes in visual snow syndrome and diagnostic use. EJNMMI Res. 2022 Dec 30;12(1):77. doi: 10.1186/s13550-022-00949-0.
- Individual participant dataSharing planned: Yes. Data can be shared on a reasonable request, including full FDG PET and MRI data as well as supporting information.
Related trials for Visual Snow Syndrome
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High-field MR Imaging in Migraine, Visual Snow and Epilepsy
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Recruiting
Study of Visual Perception Phenomena: Phosphene Mapping Induced by TMS and Its Relationship With Eye Movements
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Not yet recruiting
MBCT-vision VSS RCT
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Koen Van Laere, MD PhD principal investigator
Head Nuclear Medicine, University Hospitals Leuven
Questions about this trial
What is this clinical trial studying?
An observational study of Visual Snow Syndrome, run by Universitaire Ziekenhuizen KU Leuven.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 27 Jan 2023. Status can change between updates, so confirm with the study contact before making plans.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Group difference in regional brain metabolism as assessed with 18F-FDG positron emission tomography (time frame: analysis done immediately after imaging). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT05569733, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 27 Jan 2023.