A new concept in the pathogenesis of drusen formation in age-related macular degeneration

    Abstract

    A new concept in the pathogenesis of drusen formation in age-related macular degeneration

    I.M. Kornilovskiy

    National Medical and Surgical Center n.a. N.I. Pirogov, Moscow

    Purpose. To discuss a new concept of pathogenesis of drusen formation in patients with age-related macular degeneration (AMD).

    Material and methods. A well-known concept were analyzed and a new concept of drusen formation in AMD, taking into account modern approaches to their assessment based on optical coherence tomography with multimodal visualization was presented.

    Results. The point of the new concept of drusen formation in the retina in AMD is resolved to several key pathogenetic factors of their development. The first factor is associated with age-related and oxidative disorders of the metabolic and trophic function of the retinal pigment epithelium (PE), which phagocytising waste disks of photoreceptor membranes, does not process them to low-molecular products. The second factor is determined by the fact that the metabolic by-product of PE cells of greater molecular weight do not pass through the Bruch membrane. The third factor is determined by reducing the removal of metabolic products from the retina by intraocular fluid (IF) dialysis along oncotic pressure gradient, which creates plasma proteins that circulate in the choroid, whose blood filling is disrupted with age.

    Conclusion. Age-related and oxidative disorders of metabolic and trophic function in retinal pigment epithelium cells lead to insufficient processing of phagocytic disks of photoreceptor membranes to low-molecular fractions. In this case, the allocation of metabolic products of greater molecular weight by pigment epithelium cells violates their passage through the Bruch membrane during transretinal dialysis of IF. These processes can be considered as key factors in drusen formation in AMD.

    Key words: drusen, pigment epithelium, retina, phagocytosis, retinal dialysis of IP, AMD.