issue 6/2026
Kermedchieva , R., Daskalov, V., Daskalov, T.
Eye Hospital Pentagram – Sofia
Age-related macular degeneration (AMD) affects millions of people worldwide and is the leading cause of blindness worldwide. AMD is divided into two main types: the dry form, which accounts for 80% to 85% of all cases and usually has a more favorable visual prognosis, and the neovascular (wet) form, which affects the remaining 15% to 20% and causes severe vision loss in 80% of cases. The dry form is characterized by progressive damage and atrophy of retinal pigment epithelial (RPE) cells and concomitant loss of the underlying choriocapillaris (CC). The presence of drusen is considered a hallmark of the earlier stages of the dry form of AMD, which may coalesce and evolve into drusen-like detachment of the RPE. Lipofuscin formation has been observed when mitochondrial fission is inhibited, and impaired mitochondrial function during aging is an important element in the pathogenesis of AMD. Several studies have shown that therapeutic approaches targeting RPE mitochondria may provide an effective strategy for early treatment of the disease. Photobiomodulation (PBM) is an established non-invasive biotechnology based on light energy. The non-thermal biological process is activated by specific wavelengths of light, via photoreceptor molecules, driving cellular changes leading to improved cellular function. The main intracellular photoreceptor for red (600-750 nm) and near-infrared (750-1100 nm) (FR/NIR) light is the enzyme cytochrome C oxidase (CcO) in mitochondria. In a series of clinical trials (LIGHTSITE I-III) evaluating the effect of PBM in dry AMD using the Valeda® light delivery system, improvements in visual acuity, contrast sensitivity, and reduction in macular drusen volume were reported.
Key words: AMD, photobiomodulation, drusen, valeda
Adress for correspondence:
Kermedchieva, R.
Eye Hospital „Pentagram“- Sofia
11, „Dimatar Petkov”, Str.
1309, Sofia
e-mail: rkermedchieva@yahoo.com