Effectiveness of tDCS in Paediatric Amblyopia.
试验速览
- 阶段
- 不适用
- 状态
- 招募中
- 入组人数
- 100
- 试验地点
- 1
- 主要终点
- Visual Acuity
研究概览
简要总结
The goal of this randomized, double-blind clinical trial is to determine whether transcranial direct current stimulation (tDCS) can effectively and safely improve vision in children aged 4-14 years with strabismic or anisometropic amblyopia that has not responded to conventional patching therapy.
The main questions it aims to answer are:
Does tDCS produce significant and sustained improvements in visual acuity, contrast sensitivity, and stereopsis in children with amblyopia?
Is tDCS a safe, well-tolerated, and faster alternative or complementary treatment compared with standard occlusion therapy?
Does tDCS induce functional and structural changes in the visual cortex associated with increased neuroplasticity, including modulation of GABAergic activity?
If there is a comparison group:
Researchers will compare active tDCS with sham (placebo) stimulation to see if active treatment leads to greater visual recovery and cortical changes than placebo.
Participants will:
Receive several sessions of active or sham tDCS using low-intensity electrical stimulation applied to visual brain areas.
Undergo standard visual assessments, including visual acuity, contrast sensitivity, and stereopsis.
Complete neurophysiological and neuroimaging evaluations (EEG, pattern visual evoked potentials, and functional MRI).
Provide biochemical measures related to GABA levels.
This study aims to validate tDCS as a non-invasive, child-friendly, and effective therapy that may overcome the limitations of patching and support its inclusion in paediatric clinical practice.
详细描述
Amblyopia is a neurodevelopmental visual disorder characterised by reduced visual performance despite optimal optical correction and the absence of ocular pathology. It affects up to 2-4% of children and is the leading cause of visual impairment in this population. Conventional treatment involves optical correction and patching of the contralateral (non-amblyopic) eye, which usually produces limited improvement, low therapeutic compliance and frequent relapses, highlighting the need for new approaches based on neuroplasticity.
Transcranial direct current stimulation (tDCS) is a non-invasive neuromodulation technique that can modify cortical excitability by regulating GABAergic inhibition in the primary visual cortex (V1). It has been safely used in children with attention deficit disorder, schizophrenia, epilepsy or cerebral palsy.
Preliminary data from our group show that after three sessions of tDCS on paediatric strabismic amblyopia, there are significant and sustained improvements in visual acuity, contrast sensitivity, and stereopsis at 3 months.
This project proposes a randomised, double-blind clinical trial to evaluate the efficacy, safety and optimal dosage regimen of tDCS in children aged 4 to 14 years with strabismic or anisometropic amblyopia classified as non-responsive to occlusion therapy, according to the criteria established by the Pediatric Eye Disease Investigation Group (PEDIG). Objective biomarkers will be included using electroencephalogram, visual evoked potentials (pattern) and functional magnetic resonance imaging to explore cortical functional and structural changes, together with biochemical assessment of GABA levels.
The expected outcome is to validate tDCS as an effective, rapid, and safe alternative or complementary therapy for amblyopia. Demonstrating sustained visual and cortical improvements would support its inclusion in paediatric clinical protocols and promote translational neuro-ophthalmological rehabilitation
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- Triple (Participant, Care Provider, Investigator)
入排标准
- 年龄范围
- 4 Years 至 14 Years（Child）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Children aged 4-14 years.
- •Strabismic amblyopia resistant to patching (PEDIG criteria).
- •Anisometropic amblyopia resistant to patching (PEDIG criteria).
排除标准
- •Ocular pathology.
- •Nystagmus.
- •Mental disability.
- •Cognitive delay.
- •Neurological problems incompatible with treatment.
- •Pacemakers.
- •Intracranial electrodes.
- •Implanted defibrillators.
- •Cranial pathologies.
- •Cranial lesions.
- •Withdrawal will occur upon adverse events, protocol deviation, refusal, or loss to follow-up.
研究组 & 干预措施
Group tDCS
Children aged 4 to 14 with amblyopia treated at one of the collaborating hospitals and centers, with visual acuity in the amblyopic eye between 20/32 and 20/200. They will undergo tests of visual acuity, stereoscopic visual acuity, fixation, and contrast sensitivity. The direct current will be gradually increased over 34 seconds to 2 mA, held constant for 15 minutes, and then gradually reduced to zero using NIC2® v2.1.2.0 software (Neuroelectrics®, Barcelona, Spain). The stimulating current is applied using two rubber electrodes housed in circular sponge pockets (8 cm² each) soaked in saline solution. The electrodes are placed at Oz (active/stimulating electrode, located in the visual cortex) and Cz (reference electrode).
干预措施: tDCS (Device)
Group Sham
The sham group is equipped with the same electrostimulation helmet, but the intensity protocol is set to 0 at all times. The same measurements are taken and exactly the same procedure is followed as with the experimental group.
干预措施: tDCS (Device)
结局指标
主要结局
Visual Acuity
时间窗: 3 months
Visual acuity measurements were performed by the same examiner, using a calibrated optotype at a distance of six meters, before starting treatment, after each session, one month after treatment, and three months after treatment.
Stereoscopic visual acuity
时间窗: 3 months
Stereoscopic visual acuity was measured using TNO test (with the butterfly plate corresponding to 1300" and the circular plate to 1200"), the subject places the test 40 cm away and must identify calibrated figures.
Contrast sensitivity
时间窗: 3 months
Contrast sensitivity was measured using CSV-1000 test (3, 6, 12, and 18 cycles per degree). The patient must identify scratched circles whose frequency is decreasing.
Eye Fixation
时间窗: 3 months
Eye fixation was evaluated using the Topcon Macular Integrity Assessment (MAIA) microperimeter (Topcon corporation, Tokyo, Japan), which delineates two distinct regions using 1° (P1) and 2° (P2) circles.
次要结局
未报告次要终点