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

Myopia Clinical Trial

Official title:

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

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT05594732
• Other study ID #: YFZXLDX20220802
• Status: Completed
• Phase: N/A
• Start date: September 6, 2022
• Est. completion date: October 30, 2022

Study information

• Verified date: October 2022
• Source: Shanghai Eye Disease Prevention and Treatment Center
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial 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.

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.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 81
• Est. completion date: October 30, 2022
• Est. primary completion date: October 30, 2022
• Accepts healthy volunteers: No
• Gender: All
• Age group: 7 Years to 15 Years

Eligibility

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.

Related Conditions & MeSH terms

• Myopia

Intervention

Behavioral:
• Weak outdoor light
Stay and stare far on the balcony or under the tree
• Strong outdoor light
Stay and stare far in the sunlight

Locations

Country	Name	City	State
China	Shanghai Eye Disease Prevention and Treatment Center	Shanghai	Shanghai

Sponsors (1)

Lead Sponsor	Collaborator
Shanghai Eye Disease Prevention and Treatment Center

Country where clinical trial is conducted

China, 

References & Publications (4)

Liu Y, Wang L, Xu Y, Pang Z, Mu G. The influence of the choroid on the onset and development of myopia: from perspectives of choroidal thickness and blood flow. Acta Ophthalmol. 2021 Nov;99(7):730-738. doi: 10.1111/aos.14773. Epub 2021 Feb 7. — View Citation

Mirhajianmoghadam H, Pina A, Ostrin LA. Objective and Subjective Behavioral Measures in Myopic and Non-Myopic Children During the COVID-19 Pandemic. Transl Vis Sci Technol. 2021 Sep 1;10(11):4. doi: 10.1167/tvst.10.11.4. — View Citation

Rucker F. Monochromatic and white light and the regulation of eye growth. Exp Eye Res. 2019 Jul;184:172-182. doi: 10.1016/j.exer.2019.04.020. Epub 2019 Apr 21. — View Citation

Xiong S, Sankaridurg P, Naduvilath T, Zang J, Zou H, Zhu J, Lv M, He X, Xu X. Time spent in outdoor activities in relation to myopia prevention and control: a meta-analysis and systematic review. Acta Ophthalmol. 2017 Sep;95(6):551-566. doi: 10.1111/aos.13403. Epub 2017 Mar 2. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Retinal blood flow density after relaxing for 15 minutes	Data collected from Optovue AngioVue OCT (macular blood data collected) for the dominant eye. The duration of relaxing was recorded by a timer.	Exposing to sunlight for 15 minutes
Secondary	Retinal blood flow density changes between relaxing for 5 and 15 minutes	The difference in retinal blood flow density was calculated between 5 and 15 minutes.	Retinal blood flow density after relaxing for 5 and 15 minutes