Neural Mechanisms Underlying Astigmatism

Astigmatism Clinical Trial

Official title:

The Research of the Neural Mechanisms Underlying Astigmatism

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT03735602
• Other study ID #: JYuan
• Status: Recruiting
• Phase: N/A
• Start date: July 1, 2019
• Est. completion date: December 2021

Study information

• Verified date: May 2020
• Source: Zhongshan Ophthalmic Center, Sun Yat-sen University
• Contact: Li Gu, Phd
• Phone: 15889937313
• Email: guli7[@]mail2.sysu.edu.cn
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial 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.

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.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 20
• Est. completion date: December 2021
• Est. primary completion date: March 2021
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 10 Years to 16 Years

Eligibility

Inclusion Criteria:

• high astigmatism

Exclusion Criteria:

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

Related Conditions & MeSH terms

• Astigmatism

Intervention

Behavioral:
• perceptual training
orientation discrimination task

Locations

Country	Name	City	State
China	Zhongshan Ophthalmic Center	Guangzhou	Guangdong

Sponsors (1)

Lead Sponsor	Collaborator
Zhongshan Ophthalmic Center, Sun Yat-sen University

Country where clinical trial is conducted

China, 

Outcome

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