Repeated Low-Level Red-Light Therapy for Shortening Axial Length

Repeated Low-Level Red-Light Therapy for Shortening Axial Length in Chinese High Myopia Children and Teenagers: a Prospective Single-Arm Study

The purpose of this clinical trial is to confirm the incidence and magnitude of axial length shortening after RLRL therapy in Chinese high myopia children and teenagers.

Study Overview

• Status: Active, not recruiting
• Conditions: Eye Diseases; Refractive Errors; High Myopia
• Intervention / Treatment: Device: RLRL

Detailed Description

High myopia has become a major public concern globally, which is characterized by excessive axial elongation of the eyeball. Axial elongation is accompanied by mechanical stretching and thinning of the choroid and sclera, causing vision-threatening complications. RLRL therapy is an emerging effective and safe therapy for myopia control. Previous clinical trials in China have observed clinically significant axial shortening after RLRL treatment.

The purpose of this study is to confirm and identify possible mechanism for axial length (AL) shortening after 12-month RLRL therapy in Chinese highly myopic children and teenagers aged 6-16 years. In addition to single vision spectacles, subjects will receive RLRL treatment at home under supervision of the parents according to a standard protocol. Axial length, visual acuity, cycloplegic spherical equivalent refraction, intraocular pressure, slit lamp, optical coherence tomography, optical coherence tomography angiography and ultrawide-field optical coherence tomography will be measured at 1-, 3-, 6- and 12-month follow-up visits. This trial will be extended to 3 years and follow-up visits are scheduled at 18-, 24-, 30- and 36-month.

• Study Type: Interventional
• Enrollment (Estimated): 30
• Phase: Not Applicable

Contacts and Locations

Study Locations

• China
  • Shanghai
    • Shanghai, Shanghai, China, 20041
      • Shanghai Eye Disease Prevention and Treatment Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 6 years to 16 years (Child)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

1. Provision of consent.
2. Age: ≥ 6 and ≤ 16 years at enrolment.
3. High myopia: cycloplegic sphere ≤ -6.00 diopters (D) in both eyes.
4. Willing and able to participate in all required activities of the study.
5. The children currently on myopia control treatment can be recruited if myopia control treatments (including but not limited to atropine, orthokeratology, rigid gas-permeable lenses, defocus spectacles, etc.) are discontinued for at least 2 weeks.
6. Normal fundus, tessellated fundus or with peripapillary diffuse chorioretinal atrophy.

Exclusion Criteria:

1. Secondary myopia, such as a history of retinopathy of prematurity or neonatal problems, or syndromic myopia with a known genetic disease or connective tissue disorders, such as Stickler or Marfan syndrome.
2. Pathologic myopia with signs of macula-involving diffuse chorioretinal atrophy, patchy chorioretinal atrophy, macular atrophy, lacquer cracks, myopic choroidal neovascularization or Fuchs' spots.
3. Strabismus and binocular vision abnormalities in either eye.
4. Previous any intraocular surgery affecting refractive status.
5. Other reasons, including but not limited to ocular or other systemic abnormalities, that the physician may consider inappropriate for enrolment.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: RLRL therapy; In addition to SVS, participants will be treated with RLRL twice a school day.	Device: RLRL; In addition to SVS with power for correcting distance refraction, RLRL will be performed twice per school day with an interval of at least 4 hours, each treatment last 3 minutes.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence rate (%) of axial length shortening >0.05 mm measured by the IOL Master	Incidence rate of axial length shortening > 0.05 mm is characterized as the ratio of number of participants with axial length shortening greater than 0.05 mm to the total number.	12 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change of pathologic myopia fundus META-PM grading	The swept-source optical coherence tomography is used to obtain fundus images. The fundus images are classified based on META-PM classification system	1, 3, 6 and 12 months
Incidence rates (%) of axial length shortening >0.10 mm and >0.20 mm measured by the IOL Master	Incidence rate of axial length shortening > 0.10 mm and 0.20 mm are characterized as the ratio of number of participants with axial length hortening greater than 0.10 mm and 0.20 mm to the total number.	12 months
Changes of axial length shortening (mm) among shortened eyes measured the IOL master	Changes of axial length shortening is characterized as the magnitude of axial length reduction among axial shortened eyes.	12 months
Changes in choroidal structural and perfusion parameters measured by the swept-source optical coherence tomography and optical coherence tomography angiography	Changes in choroidal structural and perfusion parameters are characterized as the difference between each follow-up visit and corresponding baseline values. Indicators include choroidal vascular index, choroidal thickness and so on.	1, 3, 6 and 12 months
Changes in retinal structures by the swept-source optical coherence tomography and optical coherence tomography angiography	Swept-source optical coherence tomography is used to measure retinal structures. The structures of nerve sensory layer, retinal pigment epithelium layer and choroid layer were observed by fundus images.	1, 3, 6 and 12 months
Changes in axial length (mm) and other biometric parameters (mm, μm) by the IOL master	The IOL Master is used to measure axial length and other biometric parameters, including corneal curvature, anterior chamber depth and white to white, etc. Change of each parameter is characterized as the difference between each follow-up visit and baseline values	1, 3, 6 and 12 months
Change of cycloplegic spherical equivalent refraction (Diopter) by the autorefractor	Cycloplegic spherical equivalent change (Diopter, D) is characterized as the difference between each follow-up visit and baseline values. Refraction with full cycloplegia is performed with an autorefractor. The data on spherical and cylindrical power and axis is automatically extracted from the autorefractor. The spherical equivalent power (D) is calculated as the spherical power (D) plus half of the cylindrical power (D)	1, 3, 6 and 12 months
Change in best corrected visual acuity (logMAR) by the Early Treatment Diabetic Retinopathy Study (ETDRS) logMAR chart	Best corrected visual acuity change is characterized as the difference between each follow-up visit and baseline values. An Early Treatment Diabetic Retinopathy Study chart with standard illumination at a distance of 4 meters is used to measure best corrected visual acuity	1, 3, 6, and 12 months
Incidence (%) of self-reported adverse events by the quesionnaire including but not limited to glare, flash blindness, and afterimages	Incidence of self-reported adverse events is the rate of self-reported adverse events over a specified period for all the subjects.	1, 3, 6 and 12 months

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Full myopia control rate (%) by the autorefractor	Cycloplegic spherical equivalent change (Diopter, D) is characterized as the difference between each follow-up visit and baseline values. Refraction with full cycloplegia is performed with an autorefractor. The data on spherical and cylindrical power and axis is automatically extracted from the autorefractor. The spherical equivalent power (D) is calculated as the spherical power (D) plus half of the cylindrical power (D). Full myopia control is defined as cycloplegic SER progression <0.25 D/year.	36 months
Morphological changes of the posterior ocular segment by the quantitative ultrawide-field optical coherence tomography	Morphological changes of the posterior ocular segment is measured using the quantitative ultrawide-field optical coherence tomography between follow-up visit and baseline.	36 months
Changes in axial length (mm) and other biometric parameters (mm, μm) by the IOL master	The IOL Master is used to measure axial length and other biometric parameters, including corneal curvature, anterior chamber depth and white to white. Change of each parameter is characterized as the difference between each follow-up visit and baseline values.	36 months
Changes in choroidal structural and perfusion parameters measured by the swept-source optical coherence tomography and optical coherence tomography angiography	Changes in choroidal structural and perfusion parameters are characterized as the difference between each follow-up visit and corresponding baseline values. Indicators include choroidal vascular index, choroidal thickness and so on.	36 months
Change in visual acuity (logMAR) by the Early Treatment Diabetic Retinopathy Study (ETDRS) logMAR chart	Visual acuity change is characterized as the difference between each follow-up visit and baseline values. An ETDRS chart with standard illumination at a distance of 4 meters is used to measure visual acuity.	36 months
Incidence (%) of self-reported adverse events by the quesionnaire including but not limited to glare, flash blindness, and afterimages	Incidence of self-reported adverse events is the rate of self-reported adverse events over a specified period for all the subjects. Subjects are asked to report any treatment-emergent adverse events, including but not limited to glare, flash blindness, and afterimages.	36 months

Collaborators and Investigators

• Sponsor: Shanghai Eye Disease Prevention and Treatment Center

Study record dates

Study Major Dates

• Study Start (Actual): November 19, 2022
• Primary Completion (Estimated): March 1, 2026
• Study Completion (Estimated): March 23, 2026

Study Registration Dates

• First Submitted: September 20, 2022
• First Submitted That Met QC Criteria: September 20, 2022
• First Posted (Actual): September 22, 2022

Study Record Updates

• Last Update Posted (Actual): March 30, 2025
• Last Update Submitted That Met QC Criteria: March 28, 2025
• Last Verified: November 1, 2024

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Myopia; Eye Diseases; Refractive Errors
• Other Study ID Numbers: HMRL-SEPTC-2022

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Data will be shared as open data after proper anonymization.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No