Visual Restoration of Losses Caused by Cortical Damage: a New Protocol to Promote Fast Recovery
试验速览
- 阶段
- 不适用
- 状态
- 招募中
- 入组人数
- 24
- 试验地点
- 2
- 主要终点
- Visual Motion Discrimination Change
研究概览
简要总结
This is a randomized, pilot interventional study in participants with visual field deficit (VFD) caused by cortical lesion. Damage to the primary visual cortex (V1) causes a contra-lesional, homonymous loss of conscious vision termed hemianopsia, the loss of one half of the visual field. The goal of this project is to elaborate and refine a rehabilitation protocol for VFD participants. It is hypothesized that visual restoration training using moving stimuli coupled with noninvasive current stimulation on the visual cortex will promote and speed up recovery of visual abilities within the blind field in VFD participants. Moreover, it is expected that visual recovery positively correlates with reduction of the blind field, as measured with traditional visual perimetry: the Humphrey visual field test or an eye-tracker based visual perimetry implemented in a virtual reality (VR) headset. Finally, although results will vary among participants depending on the extent and severity of the cortical lesion, it is expected that a bigger increase in neural response to moving stimuli in the blind visual field in cortical motion area, for those participants who will show the largest behavioral improvement after training. The overarching goals for the study are as follows: Group 1a will test the basic effects of transcranial random noise stimulation (tRNS) coupled with visual training in stroke cohorts, including (i) both chronic/subacute ischemic and chronic hemorrhagic VFD stroke participants, and (ii) longitudinal testing up to 6 months post-treatment. Group 1b will test the effects of transcranial tRNS coupled with visual training on a Virtual Reality (VR) device in stroke cohorts, including both chronic/subacute ischemic and chronic hemorrhagic VFD stroke participants. Group 2 will examine the effects of tRNS alone, without visual training, also including chronic and subacute VFD stroke participants and longitudinal testing.
详细描述
Transcranial current stimulation Noninvasive transcranial current stimulation (tCS) has been safely used in human for decades. Noninvasive current stimulation techniques use battery-powered current generator devices that have a built-in circuitry to limit the current above a certain level, typically 2 mA (milliampere). tCS has been widely used during the last decade demonstrating non-significant risk to participants (Antal et al., 2017; Brunoni et al., 2011; Iyer et al., 2005; Nitsche et al., 2008; Nitsche & Paulus, 2011) This study uses random noise (i.e. tRNS) which results in less net charge being applied than in tDCS (transcranial direct current stimulation). There is limited reporting of side effects from tCS using alternating currents (tACS) or random noise (tRNS) in the literature. Studies that have used tACS, have also reported adverse effects similar in nature to effects described in the tDCS literature, for example, headache, sensations under the electrodes and visual sensations (Antal et al., 2017; Antal et al., 2008; Brignani et al., 2013). Adverse effects that have been described in the tCS literature are described here to offer a conservative assessment of possible adverse effects. The most common side effects associated with tCS according to the most recent data available are: (Antal et al., 2017; Nitsche & Paulus, 2011; Feurra et al., 2013)
Sensations reported by subjects under the electrode for tDCS (These sensations can sometimes continue throughout and for a brief period following completion of the tCS but usually resolve shortly after the initiation of tCS):
Mild tingling (20-70%); light itching (30-40%); slight burning (10-22%); discomfort or mild pain (10-18%)
Effects reported that occur only during tCS:
Visual sensation during switching on and off the stimulation (11%)
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Factorial
- 主要目的
- Treatment
- 盲法
- Double (Participant, Investigator)
盲法说明
Group 1b is guaranteed actual stimulation.
Randomization for sham vs actual stimulation will be conducted by a predetermined member of the research team, ensuring that participants, care providers, investigators and outcome assessors all remain blinded to the intervention at the time of each assessment.
Given this is a pilot study and that both groups receive randomization over the type of stimulation we do not anticipate that randomization for enrolling subjects into group 1 or 2 is necessary.
入排标准
- 年龄范围
- 18 Years 至 80 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •18 years of age or older.
- •Presence of some intact visual cortical areas (other than primary visual cortex) in the damaged brain hemisphere. This assessment will be made from MRI or CT scans of the subject's head, which will be obtained via standard release from their neurologist.
- •First ever ischemic or hemorrhagic stroke with damage to primary visual cortex, and rendered blind over a portion of their visual field.
- •Ischemic stroke patients will be either subacute (within 6 months of their stroke) or chronic (more than 6 months)
- •Hemorrhagic stroke patients will be chronic only (greater than 6 months)
- •Must demonstrate a clear deficit in either simple or complex visual perception in portions of their visual field as measured by visual perimetry.
- •Imaging evidence that the stroke is primarily affecting the visual cortex.
- •Willing and able to participate in the study protocol and to comply with study procedures.
排除标准
- •No evidence of damage to the primary visual cortex.
- •Visual cortex damage as a result of a subsequent stroke (not primary).
- •Total cortical blindness, covering both left and right visual fields.
- •Unable to fixate visual targets precisely or unable to perform the visual training exercises as directed.
- •Complete loss of reading abilities.
- •Current or prior history of any neurological disorder other than stroke, such as epilepsy, a progressive neurologic disease (e.g. multiple sclerosis) or intracranial brain lesions other than the qualifying stroke lesion.
- •Current history of poorly controlled migraines including chronic medication for migraine prevention.
- •History of seizures, diagnosis of epilepsy, history of abnormal (epileptiform) EEG or immediate (1st degree relative) family history of epilepsy; with the exception of a single seizure of benign etiology (e.g. febrile seizure) in the judgment of the investigator.
- •History of fainting spells of unknown or undetermined etiology that might constitute seizures.
- •Past or current history of major depression, bipolar disorder or psychotic disorders, or any other major psychiatric condition.
- •Participants who are suffering from one-sided attentional neglect as determined by standard neuropsychological tests: figure cancellation and line bisection tasks.
- •Contraindication for receiving tRNS.
- •Chronic (particularly) uncontrolled medical conditions that may cause a medical emergency in case of a provoked seizure (cardiac malformation, cardiac dysrhythmia, asthma, etc.).
- •Any complex, uncontrolled/unstable or terminal medical illness.
- •Substance abuse or dependence within the past six months.
- •Medications will be reviewed by the responsible MD (Drs. Sandeep Kumar or Dan Press) and a decision about inclusion will be made based on the following: The patient's past medical history, drug dose, history of recent medication changes or duration of treatment, and combination of CNS active drugs.
- •All female participants that are pre-menopausal will be required to have a pregnancy test; any participant who is pregnant or breastfeeding will not be enrolled in the study.
- •Subjects who, in the investigator's opinion, might not be suitable for the study.
- •A hair style or head dress that prevents electrode contact with the scalp or would interfere with the stimulation (for example: thick braids, hair weave, afro, wig).
- •Additional criteria for Group 1b only: Contraindication for using VR technology, specifically an implanted medical device such as a pacemaker, implanted defibrillator, deep brain or vagal nerve stimulator. Participants with a history of seizures are already excluded per the above criteria.
研究组 & 干预措施
Computer Visual Training with Noninvasive Brain Stimulation
10 daily (Monday-Friday) 20-30 minute sessions of tRNS with visual training on the computer
干预措施: transcranial random noise stimulation (tRNS) (Device)
Computer Visual Training with Noninvasive Brain Stimulation
10 daily (Monday-Friday) 20-30 minute sessions of tRNS with visual training on the computer
干预措施: Computer Based Visual Training (Behavioral)
Visual Training with Sham Stimulation
10 daily (Monday-Friday) 20-30 minute sessions of sham stimulation with visual training on the computer
干预措施: Computer Based Visual Training (Behavioral)
Visual Training with Sham Stimulation
10 daily (Monday-Friday) 20-30 minute sessions of sham stimulation with visual training on the computer
干预措施: Sham stimulation (Device)
Noninvasive Brain Stimulation without visual training
10 daily (Monday-Friday) 20-30 minute sessions of tRNS alone
干预措施: transcranial random noise stimulation (tRNS) (Device)
Sham Stimulation without visual training
Placebo control. Simulation of tRNS without receiving any actual stimulation
干预措施: Sham stimulation (Device)
VR Visual Training with Noninvasive Brain Stimulation
10 daily (Monday-Friday) 20-30 minute sessions of tRNS with visual training on the computer
干预措施: transcranial random noise stimulation (tRNS) (Device)
VR Visual Training with Noninvasive Brain Stimulation
10 daily (Monday-Friday) 20-30 minute sessions of tRNS with visual training on the computer
干预措施: Virtual Reality Based Visual Training (Behavioral)
结局指标
主要结局
Visual Motion Discrimination Change
时间窗: After 10 days training/stimulation and after 6 months training/stimulation
Change in the motion discrimination computer or VR task after training within the blind visual field
次要结局
- Quality of Life Change(After 10 days training/stimulation and after 6 months training/stimulation)
- Visual Field Change(After 10 days training/stimulation and after 6 months training/stimulation)
研究者
Lorella Battelli
Associate Professor
Beth Israel Deaconess Medical Center