Neural, Behavioural, and Clinical Effects of tDCS in PDOC; Feasibility Study

Brain Injuries Clinical Trial

— RAINDROP  

Official title:

Sham-controlled, Double-blind, Randomised Crossover Study of the Neural, Behavioural, and Clinical Effects of Transcranial Direct Current Stimulation in Patients With a Prolonged Disorder of Consciousness; Feasibility Study

Clinical Trial Details — Status: Not yet recruiting

Administrative data

• NCT number: NCT04248946
• Other study ID #: RG_18-269
• Status: Not yet recruiting
• Phase: N/A
• Start date: July 2021
• Est. completion date: August 2022

Study information

• Verified date: April 2021
• Source: University of Birmingham
• Contact: Davinia Fernandez Espejo, PhD FHEA
• Phone: 01214145534
• Email: d.fernandez-espejo[@]bham.ac.uk
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

This study evaluates the feasibility of an experimental protocol that combines advanced multi-modal imaging of the brain with clinical and behavioural scales to characterise the neural, behavioural, and clinical effects of transcranial direct current stimulation (tDCS) for rehabilitation in PDOC

Description:

Patients with prolonged disorders of consciousness (PDOC) have very limited therapeutic options, and they often show little to no progress over time. Here, the investigators will assess whether transcranial direct current stimulation can improve patients' responsiveness. The investigators will use a protocol designed to target specific brain networks that have been shown to play a key role in explaining the lack of voluntary responses in PDOC. The study will focus on characterising the mechanisms of action of tDCS and the bases for potential individual differences in responsiveness to the stimulation across participants. This feasibility study is the first step towards developing personalised tDCS interventions to restore external responsiveness in PDOC patients. Its results will inform the design of a future trial fully powered for characterising neural, behavioural, and clinical effects of tDCS in PDOC as well as the mechanisms underlying individual differences in responsiveness.

Recruitment information / eligibility

• Status: Not yet recruiting
• Enrollment: 15
• Est. completion date: August 2022
• Est. primary completion date: August 2022
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• Aged 18 years or older

• Receiving care at a recruitment site, with a consensus clinical diagnosis of PDOC from any aetiology (i.e. traumatic or non-traumatic injury).

• Stable and with no need of mechanical support (i.e. respirator, etc.)

Exclusion Criteria:

• Scalp skin sores or any skin damage at the electrode sites

• Metallic implants in the face or skull

• Craniectomy or cranioplasty

• No evidence of auditory startle in clinical observations, or absent brainstem auditory evoked potentials in recent clinical history (if data available)

• MRI incompatible: metal plates incompatible with MRI scanners, pacemaker, inability to lay flat for prolonged periods of time, aneurysm clips, neurostimulators, brain/subdural electrodes, etc. (MRI stream ONLY)

Related Conditions & MeSH terms

• Brain Injuries
• Consciousness Disorder
• Consciousness Disorders
• Minimally Conscious State
• Persistent Vegetative State
• Vegetative State

Intervention

Other:
• Transcranial direct current stimulation
tDCS alters neural excitability in a polarity-specific manner via a weak direct electric current delivered through electrodes placed on the scalp. There are 3 types of stimulation: anodal, cathodal, and sham. In anodal tDCS, the positive electrode is placed over the target brain area to increase neuronal excitability. In cathodal tDCS, the negative electrode is placed over the target brain area to decrease neuronal excitability. Sham tDCS emulates the physical sensations of active (anodal/cathodal) tDCS but current is only delivered for a short period of time and is not enough to cause any neuromodulations

Locations

Country	Name	City	State
United Kingdom	Moseley Hall Hospital	Birmingham	West Midlands
United Kingdom	The Wellington Hospital	London

Sponsors (2)

Lead Sponsor	Collaborator
University of Birmingham	Wellington Hospital

Country where clinical trial is conducted

United Kingdom, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Retention at end of active phase	percentage of participants on study at pre-specified time points counted from the start of participation in the study (i.e., first study procedure)	through completion of active phase of study (tDCS intervention), on average 4 weeks for bedside stream and 8 weeks for MRI stream
Primary	Retention at 3 months	percentage of participants on study at pre-specified time points counted from the start of participation in the study (i.e., first study procedure). This Outcome applies to the bedside stream only	3 months after start of participation
Primary	Retention at 6 months	percentage of participants on study at pre-specified time points counted from the start of participation in the study (i.e., first study procedure). This Outcome applies to the bedside stream only	6 months after start of participation
Primary	Completion	percentage of tDCS, MRI, and electrophysiology assessments completed per polarity	through completion of active phase of study (tDCS intervention), on average 4 weeks for bedside stream and 8 weeks for MRI stream
Secondary	Structural MRI	This will include assessments of the gross macrostructure, and microstructure of brain tissue grey matter, white matter, and cerebrospinal fluid	day 1 and day 5 of tDCS each polarity
Secondary	Functional MRI in response to task instructions	This will include assessments of the BOLD (blood oxygen level-dependent) response to characterise brain activity and connectivity during command following	day 1 and day 5 of tDCS each polarity
Secondary	EEG power in the alpha band in response to task instructions	Envelope of bandpass filtered EEG data between 8-12 Hertz	days 1 and 4 of each polarity in the MRI stream and day 1 of each polarity in the bedside stream
Secondary	EEG power in the beta band in response to task instructions	Envelope of bandpass filtered EEG data between 13-30 Hertz	days 1 and 4 of each polarity in the MRI stream and day 1 of each polarity in the bedside stream
Secondary	EMG (electromyography) amplitude changes	Changes in the amplitude of the rectified EMG signal (high-pass filtered > 50Hz) in response to instructions to move	days 1-4 and day 2 of each polarity in the MRI and bedside streams respectively
Secondary	Coma recovery scale -revised	clinical diagnostic scale for disorders of consciousness. Total score ranges from 0 to 23, where higher scores mean a higher level of functioning and awareness	regularly through active phase of study (baseline and outcome assessments), on average 4 weeks for bedside stream and 8 weeks for MRI stream
Secondary	Glasgow Outcome Scale-extended	Scale for functional outcome after brain injury. Total score ranges from 1 to 8, where higher values correspond to better outcome	at 3 and 6 months after start of participation