Funktionelle Unterschiede in den Mikrozirkulationsgebieten des Auges

Zusammenfassung

Es werden die wichtigsten Mikrozirkulationsgebiete des Auges auch in ihrer funktionellen Relevanz dargestellt. Dabei wird besonders auf die enorme morphologische und physiologische Heterogenität der Durchblutung eingegangen, vor allem, wie sie in die funktionelle Gesamtsituation der Struktur (z. B. Sauerstoffabgabe durch die Irisgefäße, Kammerwasserproduktion in den Ziliarfortsatzgefäßen) eingebunden ist. Eingehender werden Choroidea und besonders retinale Gefäße besprochen. Bei den retinalen Gefäßen ist der Aspekt der Regelung (auch über Perizyten) im Hinblick auf die hohen Erfordernisse der inneren Retinaschichten besonders wichtig. Darüber hinaus wird auf die Reaktionen auf hypoxische Zustände und hier insbesondere auf die Vorgänge in den Fotorezeptoren und bei Neovaskularisation eingegangen. Darüber hinaus wird die Situation des Stoffwechsels der retinalen Ganglienzellen (Mitochondrien), des Sehnervenkopfes und Aspekte der Pathologie im Hinblick auf das Glaukom beleuchtet.

Abstract

This review describes the most important regions of microcirculation within the eye – their architecture as well as their function. A special emphasis is put on the functional heterogeneity of the microvessels and their role regarding the specific functions localised within the different regions of the eye (e.g. oxygen release by the iris capillaries, production of aqueous humor within the ciliary processes). The microvasculature of choroidea and retina will be described in more detail. The precise adjustment of the blood flow to the functional needs of the inner retina is a very important aspect in the retinal vessels. Here, also pericytes can influence the vessel calibre like in the brain capillaries. Very important is the vascular reaction in general to states of hypoxia, especially to the hypoxic and radical producing states within the photoreceptors. The following reaction of neovascularisation will also be examined. Finally, we describe the metabolic situation of the ganglion cells and nerve fibers leading to and within the optic cup also with regard to glaucoma.

Schlüsselwörter

Anatomie - Chorioidea - Retina - Gefäße

Key words

anatomy - choroid - retina - vasculature

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