LED Red Light in Modulating Choroidal Microcirculation to Retard Retinal Atrophy in Pathological Myopia

Official title

A Randomized Controlled Trial of LED Red Light in Modulating Choroidal Microcirculation to Retard Retinal Atrophy in Pathological Myopia

Overview

The goal of this clinical trial is to learn if LED repeated low-level red light (RLRL) therapy works to treat pathologic myopia in adults. It will also learn about the safety of LED-RLRL. The main questions it aims to answer are: Does LED-RLRL modulate choroidal microcirculation to retard retinal atrophy in pathological myopia? What medical problems do participants have when receiving LED-RLRL therapy? Researchers will compare with a sham device (identical in appearance but delivering \<10% of the original device's energy output) to see if LED-RLRL works to treat pathologic myopia. Participants will: Take LED-RLRL or sham LED-RLRL twice daily, 3 minutes per session, 5 days per week, for a total duration of 12 months. Visit the clinic once every 3 months for checkups and tests. Keep a diary of their symptoms and their visual perception.

Detailed description

Pathological myopia (PM) is a major cause of irreversible visual impairment and blindness in adults, characterized by progressive axial elongation, choroidal thinning, impaired choroidal microcirculation, and subsequent retinal atrophy, which currently lacks effective therapeutic interventions. Against this clinical backdrop, this prospective randomized controlled trial is designed to systematically investigate the therapeutic efficacy and safety of LED repeated low-level red light (RLRL) therapy in adult patients with PM. The core research objectives are twofold: first, to verify whether LED-RLRL can modulate choroidal microcirculatory function and thereby retard the progression of retinal atrophy in PM patients, and second, to comprehensively assess the safety profile of long-term LED-RLRL administration by monitoring adverse events. To achieve these goals, the study will adopt a randomized controlled design, where eligible participants will be randomly assigned to either the active treatment group or the sham control group. The active treatment group will receive LED-RLRL therapy, while the control group will be administered interventions using a sham device-this device is identical in appearance and operation mode to the active LED-RLRL device but has an energy output of less than 10% of the original, aiming to exclude the placebo effect. The intervention regimen for both groups is standardized: participants will receive the assigned intervention twice daily, with each session lasting 3 minutes, 5 days per week, for a continuous 12-month course. During the study period, all participants will undergo regular follow-up visits at the clinic every 3 months, where a series of comprehensive assessments will be performed, including but not limited to visual acuity measurement, fundus examination, optical coherence tomography (OCT) for choroidal thickness and retinal structure evaluation, and choroidal blood flow dynamic detection to quantify microcirculatory changes. Additionally, participants will be instructed to maintain a detailed daily diary, recording the occurrence time, duration, and severity of any subjective symptoms (e.g., eye fatigue, photophobia) as well as changes in visual perception (e.g., contrast sensitivity, visual field changes), which will serve as supplementary data for safety monitoring and efficacy evaluation. Collectively, this study is expected to provide high-quality evidence for the clinical application of LED-RLRL in the management of PM by clarifying its regulatory effect on choroidal microcirculation and its role in delaying retinal atrophy, while defining its safety boundaries.

Interventions

• Device LED red light
  An LED-RLRL device (Airdoc PBM-LED, Model No.: AI-PBM01, Beijing Airdoc Technology Co., Ltd.) was adopted. It has a working wavelength of 650 nm, with an output power of 1.39 mW at the light source, and the output power is 1.39 mW ± 0.1 mW at a position 30 mm away from the observation window glass. Twice daily, 3 minutes per session, 5 days per week, for a total duration of 12 months.
• Device Sham LED red light
  A sham LED-RLRL device (identical in appearance but delivering \<10% of the original device's energy output) . Twice daily, 3 minutes per session, 5 days per week, for a total duration of 12 months.

Primary outcome measures

• Choroidal vascular density [Time frame: From enrollment to the end of treatment at 12 months]
• Choroidal vessel volume index [Time frame: From enrollment to the end of treatment at 12 months]

Secondary outcome measures (5)

• Choroidal thickness [Time frame: From enrollment to the end of treatment at 12 months]
• Distance between Bruch's membrane and choroidal-scleral interface [Time frame: From enrollment to the end of treatment at 12 months]
• Retinal thickness [Time frame: From enrollment to the end of treatment at 12 months]
• Retinal vascular density [Time frame: From enrollment to the end of treatment at 12 months]
• Proportion of participants developed diffuse chorioretinal atrophy [Time frame: From enrollment to the end of treatment at 12 months]

Eligibility criteria

Inclusion criteria

• Age range: 18 to 55 years old;
• Baseline visual acuity: Best Corrected Visual Acuity (BCVA) ≥ 0.1 (LogMAR ≤ 1.0);
• Meeting the diagnostic criteria for high myopia: Spherical Equivalent (SE) ≤ -6.00 D and Axial Length (AL) ≥ 26.0 mm;
• Meeting one of the following pathological fundus changes:

(i) Fundus manifestations corresponding to Category 2 (diffuse chorioretinal atrophy), Category 3 (patchy chorioretinal atrophy), or Category 4 (macular atrophy associated with choroidal neovascularization) of the META-PM classification criteria\*; (ii) Category 1 of the META-PM classification criteria\* complicated with macular schisis; (iii) BCVA < 0.6;

Exclusion criteria

• Concurrent with other ophthalmic diseases that may affect visual acuity or outcome assessment, including active myopic choroidal neovascularization (CNV) requiring anti-VEGF therapy, macular hole, vitreous hemorrhage, diabetic retinopathy, retinal detachment, retinal vein occlusion, optic neuritis, uveitis, severe cataract, and glaucoma;
• Systemic contraindications: Photosensitive epilepsy, autoimmune diseases (e.g., systemic lupus erythematosus), or pregnant/lactating women; Patients who have undergone intraocular surgery, laser treatment, or ophthalmic medication therapy within 3 months prior to enrollment;
• Patients unable to comply with regular follow-up (e.g., due to remote residence) or with cognitive impairment;
• Opaque refractive media that hinder fundus examination.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Triple blind

Primary purpose

Treatment

Study locations

China · 1 center

• Shanghai Eye Disease Prevention and Treatment Center — Shanghai

Publications

• Zhang J, Yu J, Wang X, Sun T, Zou YL, Zou H, Xu Y. LED red light for atrophy and microcirculation in pathologic myopia (RAMP): study design and protocol for a multicentre randomised controlled trial. BMJ Open. 2026 Apr 6;16(4):e117063. doi: 10.1136/bmjopen-2026-117063. PMID 41942156

Identifiers

NCT: NCT07312214 · EC-20250506-04

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗