Clinical trial NCT05016830: Bilateral Transcranial Direct Current Stimulation and Ocular Occlusion for Adults With Amblyopia
Official title: Effect of the Combination of tDCS and Visual Occlusion Therapy on Visual Acuity, Contrast Vision and Depth Vision, in Adult Patients With Amblyopia
Study type: INTERVENTIONAL
Overall status: TERMINATED
Phase: NA
Conditions: Amblyopia
Keywords: Lazy eye syndrome
Transcranial direct current stimulation
Ocular occlusion
Amblyopia
Lead sponsor: University of Chile
Sponsor class: OTHER
First posted: 2021-08-23
Enrollment: 12
Sex: ALL
Minimum age (years): 18
Maximum age (years): 65
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: A randomized, controlled pilot trial, that consists in two groups: a control group that receives sham stimulation and ocular occlusion, and a second group that receives bilateral transcranial direct current stimulation and ocular occlusion.
Primary purpose: TREATMENT

Brief summary: A prospective interventional study is expected to be conducted, to test a possible new treatment for amblyopia (lazy eye syndrome). Bilateral transcranial direct current stimulation (tDCS) is a type of noninvasive brain stimulation, which may help in visual function recovery of adult patients with amblyopia. This pilot study will test the feasibility of said therapy, along with the short term effects of bilateral tDCS in visual function.

Detailed description: Theoretical Framework: Ocular occlusion treatment has been used classically and with excellent results for the treatment of amblyopia in those under 14 years of age, since in this period it has been seen that there is greater neuroplasticity, leaving little to do in the period of lower neuroplasticity, in young and adult patients with later diagnoses. Transcranial Direct Current Stimulation therapy is an emergent technique used in neurological diseases to increase neuroplasticity, by changing the resting potential of neurons. Our hypothesis is that the combination of tDCS and visual occlusion therapy is capable of increasing visual acuity, contrast sensitivity, and depth perception, in young people over 18 years of age.

Methodology: The application of a double-blind, randomized clinical trial is proposed to evaluate the application of 2 different therapies: Occlusion with bilateral tDCS, and Occlusion with tDCS sham (sham). The study subjects will be randomly assigned to a group, and one session of stimulation will be performed. Data will be analyzed using Student's t test, or Mann-Whitney test, according to the normal or non-normal distribution of the sample, respectively. Also, the change over time of the variables will be measured using the Conditional Change Model.

Expected Results: The investigators expect that visual acuity, contrast vision, and dichoptic vision in the Occlusion therapy group with bilateral tDCS will be significantly higher than the Occlusion therapy group with tDCS sham (sham).

Eligibility criteria: Inclusion Criteria:

* Prior diagnosis of Amblyopia

Exclusion Criteria:

* Ophthalmologic disease other than amblyopia
* Chronic pharmacological therapy
* Implanted medical device
* Neurologic disease or surgery history
* History of an adverse reaction to tDCS
* Pregnancy
* Not able to give informed consent

Primary outcomes:
measure: Visual Acuity
timeFrame: 1-2 hours
measure: Visual Sensitivity
timeFrame: 1-2 hours
measure: Stereopsis
timeFrame: 1-2 hours
measure: Visual evoked potentials
timeFrame: 1-2 hours
Secondary outcomes:
Other outcomes:
Locations:
city: Santiago
country: Chile
facility: Faculty of Medicine of University of Chile
state: Region Metropolitana
Study officials:
affiliation: University of Chile
name: Romulo A Fuentes Flores, PhD
role: PRINCIPAL_INVESTIGATOR
References: