LIGHTSITE II Randomized Multicenter Trial: Evaluation of Multiwavelength Photobiomodulation in Non-exudative Age-Related Macular Degeneration

Photobiomodulation efficacy in age-related macular degeneration: a systematic review and meta-analysis of randomized clinical trials

BACKGROUND

Age-related macular degeneration (AMD) is a leading cause of vision loss. Photobiomodulation (PBM) offers a controversial approach for managing dry AMD, aiming to halt or reverse progression through mitochondrial activity modulation. However, the efficacy and clinical relevance of PBM as a potential approach for managing dry AMD remain debated.

METHODS

We systematically searched PubMed, Embase, and Cochrane databases for randomized controlled trials (RCTs) comparing PBM versus a sham in patients with dry AMD. We performed trial sequential analysis (TSA) and minimal clinically important difference (MCID) calculations to assess statistical and clinical significance applying a random-effects model with 95% confidence intervals (CI).

RESULTS

We included three RCTs comprising 247 eyes. The pooled analysis showed that PBM significant improved BCVA (MD 1.76 letters; 95% CI: 0.04 to 3.48) and drusen volume (MD -0.12 mm³; 95% CI: -0.22 to -0.02) as compared with a sham control. However, the TSA indicated that the current sample sizes were insufficient for reliable conclusions. No significant differences were observed in GA area. The MCID analysis suggested that the statistically significant results did not translate into clinically significant benefits. In the quality assessment, all studies were deemed to have a high risk of bias.

CONCLUSION

This meta-analysis points limitations in the current evidence base for PBM in dry AMD treatment, with issues around small sample sizes. Statistically significant improvements do not translate into clinical benefits. The research underscores need for larger RCTs to validate PBM's therapeutic potential for dry AMD.

Improvement in Central Serous Chorioretinopathy Following Multiwavelength Photobiomodulation Treatment - Case Report

INTRODUCTION

Central serous chorioretinopathy (CSCR) is a condition where fluid build-up accumulates underneath the retina, resulting in retinal pigment epithelium (RPE) detachment and vision loss. Irreversible retinal functional and anatomical changes are possible consequences. Research into novel strategies to aid in recovery are of interest. Photobiomodulation (PBM) uses light wavelengths to improve cellular function and shows positive effects in several conditions including those with edema.

METHODS

This prospective case report details a 39-year-old woman with CSCR. Multiwavelength PBM treatment was initiated with the Valeda® Light Delivery System. A series of treatment included nine sessions delivered over 3-5 weeks. Follow-up treatments were conducted. Optical coherence tomography (OCT) imaging and best-corrected visual acuity (BCVA) measures were taken. The patient has been followed for approximately 1 year.

RESULTS

The patient presented with blurred vision and a BCVA score of 65 letters in the left eye. After 3 weeks of observation, the patient's vision had further declined two lines on the Early Treatment Diabetic Retinopathy Study (ETDRS) chart to 55 letters. Fluorescein angiography was performed, confirming CSCR diagnosis, and PBM was initiated. PBM treatment improved BCVA and fluid build-up in the RPE within 1 week of treatment (three treatment sessions). Following the full series of treatment (nine PBM treatment sessions), fluid was completely resolved and BCVA scored at 80 letters. The patient had a repeat PBM treatment series ~ 6 months later and has shown stable vision and no fluid present on OCT scan. The patient was seen again ~ 1 year later with continued stable vision and no fluid detection.

CONCLUSIONS

PBM is a non-invasive treatment option that may provide benefit in CSCR to resolve fluid build-up, macular change, and vision loss. Research into PBM as an immediate treatment option for CSCR, especially those with chronic presentations or those posed to have irreversible damage, is warranted to confirm effectiveness.

LIGHTSITE III: 13-Month Efficacy and Safety Evaluation of Multiwavelength Photobiomodulation in Nonexudative (Dry) Age-Related Macular Degeneration Using the Lumithera Valeda Light Delivery System

PURPOSE

The LIGHTSITE III study evaluated multiwavelength photobiomodulation (PBM) therapy in nonexudative (dry) age-related macular degeneration (AMD) using the LumiThera Valeda Light Delivery System.

METHODS

LIGHTSITE III is a randomized, controlled trial to assess the safety and effectiveness of PBM in dry AMD. Subjects were given multiwavelength PBM (590, 660, and 850 nm) or Sham treatment delivered in a series of nine sessions over 3 to 5 weeks every four months over 24 months. Subjects were assessed for efficacy and safety outcomes. Data from the 13-month analysis are presented in this report.

RESULTS

A total of 100 subjects (148 eyes) with dry AMD were randomized. LIGHTSITE III met the primary efficacy best-corrected visual acuity endpoint with a significant difference between PBM (n = 91 eyes) and Sham (n = 54 eyes) groups (Between group difference: 2.4 letters (SE 1.15), CI: -4.7 to -0.1, P = 0.02) (PBM alone: 5.4 letters (SE 0.96), CI: 3.5 to 7.3, P < 0.0001; Sham alone: 3.0 letters (SE 1.13), CI: 0.7-5.2, P < 0.0001). The PBM group showed a significant decrease in new onset geographic atrophy ( P = 0.024, Fisher exact test, odds ratio 9.4). A favorable safety profile was observed.

CONCLUSION

LIGHTSITE III provides a prospective, randomized, controlled trial showing improved clinical and anatomical outcomes in intermediate dry AMD following PBM therapy.

Multi-Wavelength Photobiomodulation Ameliorates Sodium Iodate-Induced Age-Related Macular Degeneration in Rats

Age-related macular degeneration (AMD) is a global health challenge. AMD causes visual impairment and blindness, particularly in older individuals. This multifaceted disease progresses through various stages, from asymptomatic dry to advanced wet AMD, driven by various factors including inflammation and oxidative stress. Current treatments are effective mainly for wet AMD; the therapeutic options for dry AMD are limited. Photobiomodulation (PBM) using low-energy light in the red-to-near-infrared range is a promising treatment for retinal diseases. This study investigated the effects of multi-wavelength PBM (680, 780, and 830 nm) on sodium iodate-induced oxidatively damaged retinal tissue. In an in vivo rat model of AMD induced by sodium iodate, multi-wavelength PBM effectively protected the retinal layers, reduced retinal apoptosis, and prevented rod bipolar cell depletion. Furthermore, PBM inhibited photoreceptor degeneration and reduced retinal pigment epithelium toxicity. These results suggest that multi-wavelength PBM may be a useful therapeutic strategy for AMD, mitigating oxidative stress, preserving retinal integrity, and preventing apoptosis.

Shedding Light on Photobiomodulation Therapy for Age-Related Macular Degeneration: A Narrative Review

BACKGROUND

Photobiomodulation (PBM) relies on the pathophysiological mechanism whereby red to near-infrared light can target mitochondrial activity and promote ATP synthesis. Preclinical and clinical studies have shown promising results in treating intermediate age-related macular degeneration (AMD), since PBM can produce photochemical reactions in endogenous retinal chromophores. Currently, PBM is approved by the Food and Drug Administration and by the European Medicines Agency for the treatment of intermediate AMD. This narrative review aimed to evaluate the available evidence on the effectiveness and safety of PBM in treating intermediate AMD.

METHODS

A comprehensive search was conducted using the PubMed database, employing the keywords "photobiomodulation" and "age-related macular degeneration." All English-language studies published up to June 2023 were reviewed, and the search was expanded to include relevant references from selected articles. The included publications were analyzed for this review.

RESULTS

The available studies on PBM in AMD demonstrated promising but inconsistent results. PBM showed potential in improving best-corrected visual acuity (BCVA) and contrast sensitivity (CS) in patients with AMD. Some studies also suggested a reduction in AMD lesions, such as drusen volume. However, the long-term efficacy and optimal treatment parameters of PBM in AMD remained to be fully determined due to the limitations of the available studies. These included variations in irradiation techniques, wavelengths, exposure times, and treatment sessions, making it challenging to generalize the effectiveness of PBM. Furthermore, the lack of accurate classification of AMD phenotypes in the available studies hindered the understanding of which phenotypes could truly benefit from this treatment. Finally, the strength of evidence varied among studies, with limited sample sizes, unpublished results, and only three randomized sham-controlled trials.

CONCLUSIONS

Currently, the effectiveness of PBM in promoting drusen resorption or preventing progression to advanced forms of AMD, as observed in the cited studies, remains uncertain.

Non-Invasive Treatment of Early Diabetic Macular Edema by Multiwavelength Photobiomodulation with the Valeda Light Delivery System

Purpose

Diabetes is associated with ocular complications including diabetic macular edema (DME). Current therapies are invasive and include repeated intravitreal injections and laser therapy. Photobiomodulation (PBM) is a treatment (Tx) that utilizes selected wavelengths of light to induce cellular benefits including reduction of inflammation and edema. This single-center, open-label, post-hoc analysis explored the utility of multiwavelength PBM in subjects with DME.

Methods

Analysis included review of data from patients undergoing standard clinical care with an approved and marketed PBM medical device, the Valeda® Light Delivery System. Subjects with early-stage DME with good vision (Best-corrected visual acuity (BCVA) > 20/25, logMAR > 0.1) were evaluated in clinic and treated with one series of multiwavelength PBM (Tx delivered 3x/week over 3-4 weeks; total of 9 Tx sessions). Clinical, anatomical, and safety parameters were assessed in addition to subjective quality of life.

Results

A total of 30 eyes (19 subjects) were analyzed. Subjects were predominately male (68.4%) with a mean age of 56 ± 14 years. Reductions in central retinal thickness (CRT), resolution of intraretinal fluid (IRF) and improvement in diabetic retinopathy severity scale scores were observed following PBM treatment in select patients. Baseline BCVA remained stable over the follow-up observation period of 3 months post-PBM. Approximately 64% of patients reported subjective improvements in their ocular condition and decreased influence in everyday life. Detailed OCT evaluations confirmed no safety issues related to phototoxicity up to 16 months.

Conclusion

Early-stage DME subjects treated with Valeda multiwavelength PBM showed improvements in clinical and anatomical parameters. The Valeda multiwavelength PBM approach demonstrates a favorable safety profile with no signs of phototoxicity following an independent OCT review. PBM therapy may offer an alternative, non-invasive treatment strategy with a unique mechanism and modality for patients with early-stage DME.

PHOTOBIOMODULATION THERAPY FOR LARGE SOFT DRUSEN AND DRUSENOID PIGMENT EPITHELIAL DETACHMENT IN AGE-RELATED MACULAR DEGENERATION: A Single-Center Prospective Pilot Study

PURPOSE

To evaluate visual acuity and morphologic changes after photobiomodulation (PBM) for patients affected with large soft drusen and/or drusenoid pigment epithelial detachment associated with dry age-related macular degeneration.

METHOD

Twenty eyes with large soft drusen and/or drusenoid pigment epithelial detachment age-related macular degeneration were included and treated using the LumiThera Valeda Light Delivery System. All patients underwent two treatments per week for 5 weeks. Outcome measures included best-corrected visual acuity, microperimetry-scotopic testing, drusen volume, central drusen thickness, and quality of life score at baseline and month 6 (M6) follow-up. Data of best-corrected visual acuity, drusen volume, and central drusen thickness were also recorded at week 5 (W5).

RESULTS

Best-corrected visual acuity significantly improved at M6 with a mean score gain of 5.5 letters ( P = 0.007). Retinal sensitivity decreased by 0.1 dB ( P = 0.17). The mean fixation stability increased by 0.45% ( P = 0.72). Drusen volume decreased by 0.11 mm 3 ( P = 0.03). Central drusen thickness was reduced by a mean of 17.05 µ m ( P = 0.01). Geographic atrophy area increased by 0.06 mm 2 ( P = 0.01) over a 6-month follow-up, and quality of life score increased by 3,07 points on average ( P = 0.05). One patient presented a drusenoid pigment epithelial detachment rupture at M6 after PBM treatment.

CONCLUSION

The visual and anatomical improvements in our patients support previous reports on PBM. PBM may provide a valid therapeutic option for large soft drusen and drusenoid pigment epithelial detachment age-related macular degeneration and may potentially slow the natural course of the disease.