Stochastic Resonance Applied to Amblyopia Training and the Plasticity of Brain

NCT04213066 | Completed

• 1 other identifier: A-BR-102-050-t
• Study Type: interventional
• Target: 51
• Locations: 0 countries
• Sites: N/A

Brief 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.

Conditions

Amblyopia; Amblyopia, Anisometropic

Keywords

Amblyopia; Amblyopic training; Contrast sensitivity; Grating acuity; Stochastic resonance; Visual acuity; Visual evoked potential

Outcome Measures

Primary Outcomes (4)

• Visual acuity (VA)

  Landolt C chart was used.

  Change from Baseline VA at 1, 2, 3 and 6 months

• Grating acuity (GA)

  Horizontal or vertical square-wave grating stimuli were used.

  Change from Baseline GA at 1, 2, 3 and 6 months

• Contrast sensitivity (CS)

  Circular-shape horizontal square-wave grating stimuli were used.

  Change from Baseline CS at 1, 2, 3 and 6 months

• 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 Outcomes (1)

• Total practice duration

  Throughout 6 months

Study Arms (3)

Control group

ACTIVE COMPARATOR

This group received eye-hand practice for drawing pictures.

Device: Portable tablet

Grating group

EXPERIMENTAL

This group received eye-hand practice for drawing pictures with rotating grating stimuli of various spatial frequencies.

Device: Portable tablet

Random dot group

EXPERIMENTAL

This group received eye-hand practice for drawing pictures with rotating grating stimuli of various spatial frequencies constructed by random dots of stochastic resonance.

Device: Portable tablet

Interventions

Portable tablet DEVICE

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

Control group; Grating group; Random dot group

Eligibility Criteria

• Age: 4 Years - 8 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Child (0-17)

You may qualify if:

• Participants were 4-8 years old.
• Participant had binocular or monocular best-corrected visual acuity (BCVA) of ≤0.8, or they exhibited binocular BCVA difference of ≥0.2.
• Participant had the wearing of optimal spectacle correction.

You may not qualify if:

• Children with deprivation amblyopia were excluded.
• Children with ptosis were excluded.

Sponsors & Collaborators

• National Cheng-Kung University Hospital: lead
• Chang Gung Memorial Hospital: collaborator

Related Publications (1)

• Yeh WH, Lai LJ, Chang DW, Lin WS, Lin GM, Shaw FZ. Portable rotating grating stimulation for anisometropic amblyopia with 6 months training. Sci Rep. 2021 Jun 1;11(1):11430. doi: 10.1038/s41598-021-90936-7.

  PMID: 34075118 DERIVED

MeSH Terms

Conditions

Amblyopia

Condition Hierarchy (Ancestors)

Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Vision Disorders; Sensation Disorders; Neurologic Manifestations; Eye Diseases; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Study Officials

• Fu-Zen Shaw, Professor

  Department of Pyschology, National Cheng Kung University

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: December 22, 2019
• First Posted: December 30, 2019
• Study Start: July 15, 2013
• Primary Completion: January 31, 2016
• Study Completion: January 31, 2016
• Last Updated: December 30, 2019

Record last verified: 2019-12