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Trial registered on ANZCTR


Registration number
ACTRN12623000173695
Ethics application status
Approved
Date submitted
9/02/2023
Date registered
21/02/2023
Date last updated
28/07/2024
Date data sharing statement initially provided
21/02/2023
Type of registration
Prospectively registered

Titles & IDs
Public title
Modification of Brain Rhythms on Intensity of Chronic Eye Pain
Scientific title
Efficacy of electroencephalography neurofeedback for neuropathic eye pain using a single case experimental design study with multiple baselines on four participants
Secondary ID [1] 308931 0
None
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Neuropathic Eye Pain 328937 0
Condition category
Condition code
Eye 325923 325923 0 0
Diseases / disorders of the eye
Neurological 325924 325924 0 0
Other neurological disorders

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
This study will be conducted using a single-case experimental design (SCED) with multiple baselines across participants. The SCED method involves repeatedly assessing the dependent variables (i.e., pain intensity, pain interference) for each of the participants for the duration of the trial, across all phases. This study will use a design of AB + follow-ups, where 'A' refers to the baseline phase, 'B' is the intervention phase, and there will be two follow-up phases that follow. Four participants will be randomly assigned to different baseline durations of the SCED. In this study, one week (i.e., 7 days of observation) will be considered as a stable baseline. Each baseline phase will be followed by the intervention phase, where participants will complete twenty days of 30-minute EEG neurofeedback sessions over a 4-week period. There will be a 1-week follow-up for each participant immediately after completion of the intervention. Staggered baseline phases will be used under the SCED to ensure that stability is achieved. This will mean that all participants will start their baseline phase on the same day, but the baseline for the first participant will be 7 days, the second participant will have a baseline of 10 days, the third participant will have a baseline of 13 days and the fourth participant will have a baseline of 16 days. Each baseline phase will be followed by the intervention phase, where participants will each complete twenty days of 30-minute EEG neurofeedback sessions over a 4-week period. Following the intervention phase, there will be a 1-week follow up for each participant immediately after completion of the intervention. In addition, a further 1-week follow-up will take place five weeks after completion of the intervention. At the beginning of the baseline phase, each participant will complete self-report questionnaires for the primary and secondary outcomes in the form of a pain journal. Participants will continue to complete this pain journal during the intervention and follow-up phases, in order to monitor for changes in pain intensity and pain interference. Participants will be contacted every day to ensure that they're completing their pain journals at the appropriate times.

Each EEG neurofeedback session will be self-administered by participants in their homes. Each participant will complete twenty days of 30-minute EEG neurofeedback sessions over a 4-week period. Each session is comprised of three 5-minute intervals of EEG neurofeedback, with 3-minute breaks in between. Before starting each EEG neurofeedback session, participants will run an impedance check, to ensure the EEG device is positioned correctly and is accurately recording brain activity. The EEG neurofeedback treatment incorporates an EEG headset used to record and capture brain activity to be developed in-house and the interactive gaming interface that has been developed using the Unity3D game engine (Unity Technologies, USA). The neuromodulation treatment protocol targets and suppresses theta and low alpha (4-8 Hz) and high beta (20-30 Hz) frequency band powers and enhances high alpha (9-12 Hz) frequency band powers, which teaches participants to enter a mindful state, dampening pain signalling. During each EEG neurofeedback session, neurofeedback will be performed by recording and capturing the frequency bands of interest (i.e., 4-8 Hz, 9-12 Hz and 20-30 Hz) and relaying the information to the interactive gaming interface, which then provides visual feedback based on the activity recorded: when only one EEG frequency band power is suppressed or reinforced as desired, the game avatar will change colour; when two frequency band powers are activated correctly, the game avatar starts to move forward; and when all three frequency band powers are activated, the gaming background changes colour which indicates that participants have entered a mindful state. Participants will accumulate points for the amount of time they spend in this mindful state (i.e., number of seconds that a participant keeps all three frequency power bands activated). Hence, the aim of the game is to accumulate as many points as possible.
Intervention code [1] 325381 0
Treatment: Devices
Comparator / control treatment
No control group, as the EEG neurofeedback intervention will be compared to a no treatment baseline.
Control group
Active

Outcomes
Primary outcome [1] 333779 0
The Numerical Rating Scale (NRS) will serve as the primary outcome measure of neuropathic eye pain. The NRS assesses pain intensity on a 0-10 scale (0 = "no pain" and 10 = "maximum pain imaginable").
Timepoint [1] 333779 0
Participants in this study will be asked to rate the average intensity of their pain at the same time on one occasion each and every day, for the duration of the trial. If by the end of the trial any ratings are missing, the score will be averaged using the ratings obtained. Pain intensity will be recorded by participants in their pain journals, using paper-and-pencil. They will record pain intensity every day during all phases: baseline (7, 10, 13 or 16 days), intervention (28 days), and two follow-up (7 days) phases.
Secondary outcome [1] 418274 0
The degree of pain interference experienced by each participant will be assessed using 6 items from the Brief Pain Inventory. These items assess how each participant's eye pain interferes with aspects of daily life: general activity, normal work, relations with other people, enjoyment of life, mood and sleep. For each of these six aspects, pain interference will be graded on a 0-10 scale ("0" = "does not interfere" and 10 = "completely interferes").
Timepoint [1] 418274 0
Like pain intensity, degree of pain interference will be measured on one occasion, every day during all phases of the trial: baseline, intervention and both follow-up phases.

Eligibility
Key inclusion criteria
Four individuals with neuropathic eye pain will be recruited for this study. Participants need to meet the following inclusion criteria: (1) a diagnosis of neuropathic eye pain based on clinical history, ocular and non-ocular pain symptoms, and structure and function of the corneal nerves, (2) neuropathic eye pain persisting for longer than 6 months, (3) average pain rating = or more than 3 over the last seven days (out of 10) on the Numerical Rating Scale (0 reflecting no pain and 10 reflecting maximum pain), (4) fluent in speaking and reading English, (5) not currently undergoing any changes to current eye pain treatment or eye procedures and (6) able to fully participate in the EEG neurofeedback intervention and is willing to complete all 20 sessions over the four-week intervention period.
Minimum age
18 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
The key exclusion criteria are as follows: (1) diagnosis of a severe neurodegenerative and/or psychiatric disorder, (2) average pain rating < 3 over the last seven days (out of 10) on the Numerical Rating Scale (0 reflecting no pain and 10 reflecting maximum pain), (3) eye pain limiting prolonged exposure to digital screens for 20 minutes (comprises approximately one session of EEG neurofeedback), (4) individuals unable to complete twenty consecutive days of EEG neurofeedback treatment and (5) individuals located outside of Australia.

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Who is / are masked / blinded?



Intervention assignment
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
Both the primary and secondary outcome measures will be analysed separately, based on SCED analysis. Although SCED analysis primarily relies on visual inspection, both visual analysis and supplementary statistical analysis will be used to analyse the data from this trial. When visually analysis SCED data, a benchmark is established at baseline, which is used to compare against the data collected at intervention and during both follow-up phases, to identify any changes in the either outcome. A structured analysis will be used to investigate whether any changes to pain intensity and pain interference that were induced by the EEG are reliable and consistent across participants.

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
NSW

Funding & Sponsors
Funding source category [1] 313141 0
Charities/Societies/Foundations
Name [1] 313141 0
Rebecca L. Cooper Medical Research Foundation
Country [1] 313141 0
Australia
Funding source category [2] 313149 0
University
Name [2] 313149 0
University of New South Wales
Country [2] 313149 0
Australia
Funding source category [3] 313182 0
Government body
Name [3] 313182 0
National Health and Medical Research Council
Country [3] 313182 0
Australia
Primary sponsor type
University
Name
University of New South Wales Sydney
Address
University of New South Wales Sydney, High Street, Kensington, NSW 2052
Country
Australia
Secondary sponsor category [1] 314843 0
None
Name [1] 314843 0
None
Address [1] 314843 0
None
Country [1] 314843 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 312384 0
UNSW Human Research Ethics Committee C
Ethics committee address [1] 312384 0
Ethics committee country [1] 312384 0
Australia
Date submitted for ethics approval [1] 312384 0
01/06/2023
Approval date [1] 312384 0
11/08/2023
Ethics approval number [1] 312384 0
HC230351

Summary
Brief summary
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 124470 0
Prof Sylvia Gustin
Address 124470 0
NeuroRecovery Research Hub, Level 1, Biolink Building
University of New South Wales
Kensington, NSW 2052
Country 124470 0
Australia
Phone 124470 0
+61 2 9348 0846
Fax 124470 0
Email 124470 0
Contact person for public queries
Name 124471 0
Sylvia Gustin
Address 124471 0
NeuroRecovery Research Hub, Level 1, Biolink Building
University of New South Wales
Kensington, NSW 2052
Country 124471 0
Australia
Phone 124471 0
+61 2 9348 0846
Fax 124471 0
Email 124471 0
Contact person for scientific queries
Name 124472 0
Sylvia Gustin
Address 124472 0
NeuroRecovery Research Hub, Level 1, Biolink Building
University of New South Wales
Kensington, NSW 2052
Country 124472 0
Australia
Phone 124472 0
+61 2 9348 0846
Fax 124472 0
Email 124472 0

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
We do not yet have Ethics Approval for this trial.


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.