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Active, Not Recruiting

NCT Number: NCT05550740

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

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.

Active, Not Recruiting

This study is active but is not currently recruiting participants.

Key information

Conditions

High Myopia Eye Diseases Refractive Errors

Age range

6 year–16 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Shanghai Eye Disease Prevention and Treatment Center

Shanghai, Shanghai Municipality, 20041, China

About this study

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.

Who can participate

Healthy volunteers accepted: Yes

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

Inclusion criteria

  • Provision of consent.
  • Age: ≥ 6 and ≤ 16 years at enrolment.
  • High myopia: cycloplegic sphere ≤ -6.00 diopters (D) in both eyes.
  • Willing and able to participate in all required activities of the study.
  • 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.
  • Normal fundus, tessellated fundus or with peripapillary diffuse chorioretinal atrophy.

Exclusion criteria

  • 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.
  • Pathologic myopia with signs of macula-involving diffuse chorioretinal atrophy, patchy chorioretinal atrophy, macular atrophy, lacquer cracks, myopic choroidal neovascularization or Fuchs' spots.
  • Strabismus and binocular vision abnormalities in either eye.
  • Previous any intraocular surgery affecting refractive status.
  • Other reasons, including but not limited to ocular or other systemic abnormalities, that the physician may consider inappropriate for enrolment.

Treatment and study plan

RLRL

Device

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.

Primary outcomes

  1. Incidence rate (%) of axial length shortening >0.05 mm measured by the IOL Master

    Time frame: 12 months

    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.

Secondary outcomes

  1. Incidence rates (%) of axial length shortening >0.10 mm and >0.20 mm measured by the IOL Master

    Time frame: 12 months

    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.

  2. Changes of axial length shortening (mm) among shortened eyes measured the IOL master

    Time frame: 12 months

    Changes of axial length shortening is characterized as the magnitude of axial length reduction among axial shortened eyes.

  3. Changes in choroidal structural and perfusion parameters measured by the swept-source optical coherence tomography and optical coherence tomography angiography

    Time frame: 1, 3, 6 and 12 months

    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.

  4. Changes in retinal structures by the swept-source optical coherence tomography and optical coherence tomography angiography

    Time frame: 1, 3, 6 and 12 months

    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.

  5. Changes in axial length (mm) and other biometric parameters (mm, μm) by the IOL master

    Time frame: 1, 3, 6 and 12 months

    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

  6. Change of cycloplegic spherical equivalent refraction (Diopter) by the autorefractor

    Time frame: 1, 3, 6 and 12 months

    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)

  7. Change of pathologic myopia fundus META-PM grading

    Time frame: 1, 3, 6 and 12 months

    The swept-source optical coherence tomography is used to obtain fundus images. The fundus images are classified based on META-PM classification system

  8. Change in best corrected visual acuity (logMAR) by the Early Treatment Diabetic Retinopathy Study (ETDRS) logMAR chart

    Time frame: 1, 3, 6, and 12 months

    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

  9. Incidence (%) of self-reported adverse events by the quesionnaire including but not limited to glare, flash blindness, and afterimages

    Time frame: 1, 3, 6 and 12 months

    Incidence of self-reported adverse events is the rate of self-reported adverse events over a specified period for all the subjects.

Other outcomes

  1. Full myopia control rate (%) by the autorefractor

    Time frame: 36 months

    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.

  2. Morphological changes of the posterior ocular segment by the quantitative ultrawide-field optical coherence tomography

    Time frame: 36 months

    Morphological changes of the posterior ocular segment is measured using the quantitative ultrawide-field optical coherence tomography between follow-up visit and baseline.

  3. Changes in axial length (mm) and other biometric parameters (mm, μm) by the IOL master

    Time frame: 36 months

    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.

  4. Changes in choroidal structural and perfusion parameters measured by the swept-source optical coherence tomography and optical coherence tomography angiography

    Time frame: 36 months

    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.

  5. Change in visual acuity (logMAR) by the Early Treatment Diabetic Retinopathy Study (ETDRS) logMAR chart

    Time frame: 36 months

    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.

  6. Incidence (%) of self-reported adverse events by the quesionnaire including but not limited to glare, flash blindness, and afterimages

    Time frame: 36 months

    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.

Sponsors and collaborators

Lead sponsor

Shanghai Eye Disease Prevention and Treatment Center

Other

Registry information

Official study title

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

Important dates

Study start
2022
Primary completion
2026
Study completion
2026
First posted
Sep 22, 2022
Registry last updated
Mar 30, 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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