Neural Mechanisms Underlying Astigmatism

The Research of the Neural Mechanisms Underlying Astigmatism

Status

UNKNOWN

Phases

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT03735602

Enrollment

Registered

2018-11-08

Start date

2019-07-01

Completion date

2021-12-31

Last updated

2020-05-19

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Astigmatism

Brief summary

This study is to compare the contrast sensitivity function and neural response to gratings before and after the orientation discrimination task in the astigmatism or amblyopia patients.

Detailed description

The presence of astigmatism can lead to substantial reductions in visual performance in a variety of clinical vision measures and functional visual tasks. However, the neural mechanisms underlying the astigmatism remains unknown. The current study recruited three groups (patients with with-the-rule astigmatism and amblyopia, patients with with-the-rule astigmatism but without amblyopia, normal controls) of subjects and patients receive perceptual learning training (orientation discrimination task) which lasts for around 15 days. This main aim is to compare the contrast sensitivity function and neural response to gratings before and after the orientation discrimination task in the astigmatism or amblyopia patients. Patients with astigmatism or amblyopia were included in this study. All participants underwent an ophthalmic examination that included slit-lamp biomicroscopy, visual acuity, quick CSF under full optical correction, 9-SF life quality questionnaire and fundus examination.

Interventions

BEHAVIORALperceptual training

orientation discrimination task

Study design

Allocation

Intervention model

SINGLE_GROUP

Primary purpose

BASIC_SCIENCE

Masking

NONE

Eligibility

Sex/Gender

ALL

Age

10 Years to 16 Years

Healthy volunteers

Yes

Inclusion criteria

* high astigmatism

Exclusion criteria

* other types of disease (especially optical diseases) that may affect study

Design outcomes

Primary

Measure	Time frame	Description
The change of the contrast sensitivity function tested by quick CSF	eight months	The quick CSF (contrast sensitivity function) measures contrast threshold by fitting raw data and calculating the Cutoff sensitivity frequency.
The change of contrast threshold tested by sweep visually evoked potential (VEP)	eight months	The contrast threshold was calculated by analyzing EEG(Electroencephalogram) data recorded with sweep visually evoked potential (VEP) paradigm.

Countries

China

Contacts

Primary ContactLi Gu, Phd

guli7@mail2.sysu.edu.cn15889937313

Backup ContactJin Yuan, Professor

yuanjincornea@126.com2087333391

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026