## 3 Current Applications
### Retina  
#### 3.2.1 Age-Related Macular Degeneration  
Age-related macular degeneration (AMD) is a leading cause of vision impairment, especially in developed countries, where it stands as a major contributor to irreversible blindness among the elderly [30]. AMD involves pathological alterations affecting the deeper retinal layers of the macula and the surrounding vasculature, culminating in the loss of central vision. The hallmark clinical observation in AMD is the accumulation of retinal deposits known as drusen, which may be the first sign of the \"dry\" form of the disease. This dry form, being the predominant morphological type, can progress to the \"wet\" or neovascular AMD. In neovascular AMD, central choroidal neovascular membranes (CNV) can form, leading to hemorrhaging and exudation within the retina, ultimately resulting in profound vision impairment [31]. The AREDS classification system, widely used for age-related macular degeneration (AMD), categorizes AMD into different groups. The control group (AREDS 1) shows no or few small drusen. Early AMD (AREDS 2) involves numerous small drusen, some larger drusen, or RPE abnormalities. Moderate AMD (AREDS 3) includes medium-sized drusen and at least one large druse, with geographic atrophy not in the central macula. Advanced AMD (AREDS 4) comprises geographic atrophy of the RPE involving the macula and neovascular maculopathy, including CNV, retinal detachment, exudation, and fibrovascular proliferations, often leading to a discoid scar [32; 33]. Photobiomodulation is emerging as a potential treatment for dry AMD. This technique employs three distinct laser wavelengths (590 nm, 660 nm, and 850 nm) to primarily focus on the mitochondrial electron transport chain [34; 35]. The initial report of the use of PBM to treat AMD in humans dated 2008, when a prospective study involved 348 eyes and 203 patients affected by dry and wet AMD, using a semiconductor laser diode with continuous emission (780 nm, 7.5 mW, 292 Hz). The findings demonstrated enhanced visual acuity for both types of the disease, along with a reduction in metamorphosis, scotoma, and dyschromatopsia. Patients with wet AMD experienced improvements in edema and bleeding. The improved vision persisted for 3 to 36 months after the treatment. Notably, no changes in visual acuity were reported in the control group [36]. The ALIGHT was a single-center randomized controlled trial (RCT) conducted at Bristol Eye Hospital in Bristol, UK. The study included 60 participants with AREDS grades 2 to 4 and an ETDRS BCVA score of 0.3 logMAR or better in the study eye. Participants were randomly assigned to receive LED-PBM (505 nm) treatment or no treatment in the study eye. Photobiomodulation (PBM) was administered for 8 h every night for 12 months using the Noctura 500 mask (PolyPhotonix Medical, Ltd., Sedgefield, UK). All participants were concurrently undergoing ranibizumab injections for neovascular AMD in the fellow eye. Investigators conducted monthly assessments using optical coherence tomography (OCT) imaging to measure drusen volume and detect the development of neovascular AMD. ALIGHT demonstrated that there was no significant difference in Best-Corrected Visual Acuity (BCVA) between participants who received single-wavelength PBM and those who did not after one year. Furthermore, light therapy did not yield a significant impact on the progression of early age-related macular degeneration (AMD) throughout the 12-month duration [37]. Additionally, in the review published on the Cochrane Library conducted by [PERSON] and [PERSON], it is emphasized that in the ALIGHT study, researchers did not adhere to CONSORT guidelines ([PERSON] 2004) when reporting adverse events, as they did not provide overall absolute risk per arm or per adverse event type data. The seriousness of adverse events was not fully disclosed, and there was uncertainty regarding whether any adverse events were recurrent in the same participant ([PERSON] _et al._, 2018).