Stochastic Resonance Applied to Amblyopia Training and the Plasticity of Brain

Amblyopia Clinical Trial

Official title:

Stochastic Resonance Applied to Amblyopia Training and the Plasticity of Brain

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT04213066
• Other study ID #: A-BR-102-050-t
• Status: Completed
• Phase: N/A
• Start date: July 15, 2013
• Est. completion date: January 31, 2016

Study information

• Verified date: December 2019
• Source: National Cheng-Kung University Hospital
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

The prevalence of Taiwan's population with amblyopia is 2-5%. Amblyopia affects the daily life and learning ability. The human visual system can be developed normally with exposure of clear images on the retina, which often drive the development and projection of optic nerves progressively. In general, the visual acuity progresses gradually with age. A normal vision is relatively mature until 8 years old. Several types of amblyopia (strabismic amblyopia, refractive amblyopia, and deprivation amblyopia) are identified. The refractive amblyopia and deprivation amblyopia must be corrected by wearing glasses or surgeries. Otherwise, amblyopia is often corrected by occlusion of the dominant eye or amblyopia training. The Cambridge Stimulator (CAM) with rotating grating is commonly used in clinic in Taiwan. The principle of the CAM allows subjects to draw pictures on the plate in coincidence with occlusion of the dominant eye. The parents have to go with their children to a hospital weekly. The CAM training is a stereotyped visuomotor behavior, which usually causes fatigue and uninteresting results for children.

Recently, some computer games have been incorporated with CAM training. However, their clinical impact on amblyopia is largely unknown. Moreover, most of studies don't have long-term tracking, and they only use limited assessments. In this project, a home-based training would be built for children with amblyopia. A CAM training with a hierarchical structure with story-based organization would be implemented in the tablet. It will save time for children and parents for traffic between the home and hospital. The CAM training with organized structure would increase acceptability and create subjects' motivation for long-term training. In addition, a stochastic resonance theory would be incorporated with the CAM training to potentiate the learning curve of a visuomotor skill in young children. Five systematic assessments, including visual acuity, grating acuity, contrast sensitivity, and 2 measurements of visual evoked potentials (VEPs), would be used. The investigators hypothesized that the rotating grating stimulation and stochastic resonance stimulation groups showed significant enhancement of the visual functions compared with the control group and performance of the VEPs toward better eye through the home-based training apparatus.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 51
• Est. completion date: January 31, 2016
• Est. primary completion date: January 31, 2016
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 4 Years to 8 Years

Eligibility

Inclusion Criteria:

1. Participants were 4-8 years old.

2. Participant had binocular or monocular best-corrected visual acuity (BCVA) of =0.8, or they exhibited binocular BCVA difference of =0.2.

3. Participant had the wearing of optimal spectacle correction.

Exclusion Criteria:

1. Children with deprivation amblyopia were excluded.

2. Children with ptosis were excluded.

Related Conditions & MeSH terms

• Amblyopia
• Amblyopia, Anisometropic

Intervention

Device:
• Portable tablet
Each training session was limited to 15 minutes a day, 5 days a week. The entire training period was 6 months.

Locations

Country	Name	City	State
n/a

Sponsors (2)

Lead Sponsor	Collaborator
National Cheng-Kung University Hospital	Chang Gung Memorial Hospital

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Visual acuity (VA)	Landolt C chart was used.	Change from Baseline VA at 1, 2, 3 and 6 months
Primary	Grating acuity (GA)	Horizontal or vertical square-wave grating stimuli were used.	Change from Baseline GA at 1, 2, 3 and 6 months
Primary	Contrast sensitivity (CS)	Circular-shape horizontal square-wave grating stimuli were used.	Change from Baseline CS at 1, 2, 3 and 6 months
Primary	Visual evoked potential (VEP)	Transient VEP and Steady state VEP of the Cortical EEG were recorded.	Change from Baseline VEP at 1, 2, 3 and 6 months
Secondary	Total practice duration	Practice duration was recorded in the tablet.	Throughout 6 months