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NCT Number: NCT06853691

The Effects of Glasses-Free 3D Training on Visual and Cognitive Function in Presbyopic Individuals

This study aims to evaluate the effectiveness of glasses-free 3D visual training in improving visual function, visual comfort, and the application ability of visual functions in individuals with presbyopia. The research will assess changes in brain activity related to visual processing using Electroencephalogram(EEG)and Functional near-infrared spectroscopy(NIRS) before and after the training. By examining the impact of stereoscopic stimulation on the functional connectivity of brain regions, the study seeks to provide new insights into the rehabilitation of presbyopia and its underlying mechanisms. The goal is to offer a non-invasive and scientifically supported approach to improving presbyopia treatment, potentially advancing clinical practices and contributing to brain science and ophthalmology

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Key information

Age range

40 year–60 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Zhongshan Opthalmic Center, Sun Yat-sen University

Guangzhou, Guangdong, 510060, China

Location contact

Yehong Zhuo, professor

CONTACT

[email protected]

020-66619349

About this study

Presbyopia is a manifestation of aging, and the prevalence of presbyopia increases with age. About 1.7 to 2 billion people in the world have presbyopia. According to the criteria proposed by Hofstetter in 1950, presbyopia symptoms begin to appear in different individuals from the age of 40, and complete presbyopia occurs at the age of 60. With the occurrence of presbyopia, there will be a series of accompanying diseases, such as the decrease of contrast sensitivity, leading to visual discomfort. Moreover, near work is difficult and even affects daily life.

Conventional ophthalmic analysis and intervention are sufficient. Although invasive correction methods can achieve satisfactory visual quality, there is a certain surgical risk. It is necessary to consider not only the patient's general condition, but also the follow-up care. Some monocular correction at the cost of binocular stereoscopic vision will cause the damage of depth perception and seriously affect stereoscopic vision. Non-invasive methods also have certain limitations, such as glasses correction will increase the risk of falls due to the surrounding jumping and swimming effects, the effect of drugs is temporary, and will cause a series of adverse reactions. The glasses-free 3D vision training equipment is simple to operate, easy to implement the training process, and the content is variable, and no other equipment is needed. Due to the popularity of video terminals, the prevalence of electronic device related asthenopia is also increasing. In order to explore the improvement of accommodation function and the relief of asthenopia after glasses-free 3D training, a randomized controlled trial was designed. The effects of this training on the central nervous system were analyzed by electroencephalogram (EEG) and near-infrared spectroscopy (fNIRS).

The aim of this study is to evaluate the improvement of visual function, application ability of visual function, and visual comfort in patients with presbyopia through the intervention of glasses-free 3D visual training, and to evaluate the functional changes of brain visual-related areas in patients with presbyopia before and after the training combined with EEG and NIRS. To explore the effects of stereoscopic stimulation on the functional connectivity of brain regions and different frequency bands. To explore the scientific nature and effectiveness of glasses-free 3D visual training in the rehabilitation of presbyopia, to provide a new theoretical basis and method for the clinical treatment of presbyopia, and to provide more information and clues for exploring the complex stereo vision imaging mechanism in the fields of brain science and ophthalmology.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Age 40-60 years old, both sexes;
  • refractive error -6.0D to 5.0D, astigmatism <2.0D, anisometropia <4.0D;
  • binocular corrected visual acuity <0.2LogMAR;
  • stereoscopic threshold ≤100 ';
  • The subjects could understand the purpose of this study and sign the informed consent.

Exclusion criteria

  • after lens replacement; People with cataracts, which affect vision, have other eye conditions such that simultaneous vision is not possible;
  • using any medication known to affect accommodative function or wearing orthokeratology lenses in the past 1 month;
  • patients with severe systemic disease or severe mental illness;
  • Other situations where the investigator considers that the subject should not participate in the study for safety reasons or the interests of the patient.

Treatment and study plan

glasses-free 3D visual training

Other

Trail group Conduct 15 minutes of naked-eye 3D vision training. Twice a day, five days a week.

Control groups The subjects watched ordinary 2D videos for 15 minutes each time, all under the same lighting conditions. This was done twice a day, five days a week.

Primary outcomes

  1. Amplitude of accommodation

    Time frame: Baseline and after 6 and 12 weeks of training

    The push-up method combined with negative lens method was used. The measurements were completed by a comprehensive refractometer. It was performed according to the methods in Clinical Procedures for Ocular Examination 4th

Secondary outcomes

  1. Asthenopia scale

    Time frame: Baseline and after 6 and 12 weeks of training

    The asthenopia scale consisted of 2 self-assessment items (" Do you have symptoms of asthenopia "and" does eye fatigue affect your study, work or life ") and 19 symptom items (" Do you feel discomfort around the eyes ")

  2. Vergence facility

    Time frame: Baseline and after 6 and 12 weeks of training

    Vergence facility was tested using a lens flipper (3△BI/12△BO lens combination per eye) at 40cm with near correction

  3. Accommodative convergence to accommodation(AC/A)

    Time frame: Baseline and after 6 and 12 weeks of training

    Accommodative response was measured by WAM-5500. Additional accommodative and vergence stimuli were provided by spherical lenses

  4. The node efficiency

    Time frame: Baseline and after 6 and 12 weeks of training

    Electroencephalogram (EEG) was performed to track the electrical activity of the brain in real-time, and the node efficiency was calculated.

    Node efficiency is a metric that characterizes the efficiency of a single node in connecting with all other parts of the network. It reflects the centrality and importance of a node within the network.

  5. Hemodynamic response functions

    Time frame: Baseline and after 6 and 12 weeks of training

    Functional near-infrared spectroscopy (fNIRS) was conducted to capture spatial information on cerebral blood flow and oxygenation conditions. Therefore, a hemodynamic response function was constructed through it.

  6. Convergence accommodation to convergence(CA/C)

    Time frame: Baseline and after 6 and 12 weeks of training

    Accommodative response was measured by WAM-5500,Additional accommodative and vergence stimuli were provided by prisms

  7. Functional connectivity network

    Time frame: Baseline and after 6 and 12 weeks of training

    Electroencephalogram (EEG) was performed to track the electrical activity of the brain in real-time, and the functional connectivity network was calculated.

    Functional connectivity represent changes in brain activity in time domain and frequency domain respectively through correlation and coherence.

  8. Negative relative vergence

    Time frame: Baseline and after 6 and 12 weeks of training

    Negative relative vergence were measured by base in prism at 40cm with near correction

  9. Positive relative vergence

    Time frame: Baseline and after 6 and 12 weeks of training

    Positive relative vergence were measured by base out prism at 40cm with near correction

Other outcomes

  1. Accommodative facility

    Time frame: Baseline and after 6 and 12 weeks of training

    Accommodative facility was tested using a lens flipper (+0.5D/-0.5 D lens combination) at 1m with distance correction

  2. Refraction and addition(near correction)

    Time frame: Baseline and after 6 and 12 weeks of training

    In a semi-dark room, the Subjective Refraction and addition(ADD) measurements were performed. Thus, the subjects' near correction prescription were obtained

  3. Near point of convergence

    Time frame: Baseline and after 6 and 12 weeks of training

    Near point of convergence was measured using push-up method with near correction

Study contacts

Contact information is provided by the study sponsor or research team.

Jinan Zhan

CONTACT

[email protected]

15015072151

Yehong Zhuo, professor

CONTACT

[email protected]

020-66619349

Sponsors and collaborators

Lead sponsor

Zhongshan Ophthalmic Center, Sun Yat-sen University

Other

Registry information

Important dates

Study start
2025
Primary completion
2025
Study completion
2026
First posted
Mar 3, 2025
Registry last updated
Mar 3, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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