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The Effects of Different Outdoor Light Exposure Modes on Retinal Blood Flow

The Effects of Different Outdoor Light Exposure Modes on Retinal Blood Flow in School Students: a Randomized Controlled Trial

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05594732
Enrollment
81
Registered
2022-10-26
Start date
2022-09-06
Completion date
2022-10-30
Last updated
2023-06-08

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

Conditions

Myopia

Keywords

myopia, retinal blood flow, accommodative micro-fluctuation, outdoor light exposure

Brief summary

In 2020, the overall myopia rate among children and adolescents in my country was 52.7%. The COVID-19 pandemic has increased students' time of indoor eye-using, and it showed that the light exposure intensity of myopic students is lower than that of non-myopia students. Studies have found that the light wave bandwidth has a significant impact on the emmetropization of the eye, and white light can promote emmetropia more than monochromatic light. It shows that outdoor exercise has a protective effect on the occurrence and development of myopia in children and adolescents, but the specific mechanism is still unclear. Retinal blood flow is sensitive to myopic stimuli, and is a short-term indicator of the relationship between light environment and myopia. This study selected retinal blood flow as the primary outcome, aiming to compare the effects of different outdoor light exposure modes on retinal blood flow after 1 hour of intense eye use, and provide clues for the prevention and control of myopia.

Detailed description

In 2018, eight departments including the Ministry of Education jointly issued the Implementation Plan for Comprehensive Prevention and Control of Myopia in Children and Adolescents. As of 2020, the overall myopia rate among children and adolescents in my country was 52.7%. The COVID-19 pandemic has increased students' time of indoor eye-using, and it showed that the light exposure intensity of myopic students is lower than that of non-myopia students. Studies have found that the light wave bandwidth has a significant impact on the emmetropization of the eye, and white light can promote emmetropia more than monochromatic light. It shows that outdoor exercise has a protective effect on the occurrence and development of myopia in children and adolescents, but the specific mechanism is still unclear. Retinal blood flow is sensitive to myopic stimuli, and is a short-term indicator of the relationship between light environment and myopia. Also, there is a theory that reduced choroidal blood flow causes scleral hypoxia, which leads to the development of myopia. Therefore, this study selected retinal blood flow as the primary outcome, aiming to compare the effects of different outdoor light exposure modes on retinal blood flow after 1 hour of intense eye use, and provide clues for the prevention and control of myopia.

Interventions

BEHAVIORALWeak outdoor light

Stay and stare far on the balcony or under the tree

BEHAVIORALStrong outdoor light

Stay and stare far in the sunlight

Sponsors

Shanghai Eye Disease Prevention and Treatment Center
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
SINGLE (Subject)

Masking description

The participants were randomly divided into two groups without knowing the exposing mode.

Intervention model description

The participants were randomly divided into the following two groups: 1. 4000Lux natural light exposure; 2. 10000Lux natural light exposure.

Eligibility

Sex/Gender
ALL
Age
7 Years to 15 Years
Healthy volunteers
No

Inclusion criteria

* School students aged from 7 to 15, regardless of sex or gender; * Diopter between -2.0D and 3.0D, and astigmatism not exceed 0.75D; * No organic disease and in good general condition; * Have obtained the consent of their parents or guardians, and can cooperate.

Exclusion criteria

* Suffering from amblyopia, strabismus, color weakness, congenital cataract, glaucoma and other eye diseases; * Other circumstances judged by the investigator to be unsuitable to participate in the research.

Design outcomes

Primary

MeasureTime frameDescription
Retinal blood flow density after relaxing for 15 minutesExposing to sunlight for 15 minutesData collected from Optovue AngioVue OCT (macular blood data collected) for the dominant eye. The duration of relaxing was recorded by a timer.

Secondary

MeasureTime frameDescription
Retinal blood flow density changes between relaxing for 5 and 15 minutesRetinal blood flow density after relaxing for 5 and 15 minutesThe difference in retinal blood flow density was calculated between 5 and 15 minutes.

Countries

China

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 6, 2026