SATURDAY 9TH SEPTEMBER
The topography of vitreal-zonular-lenticular complex
PURPOSE: The aim of the present study was to reveal the zonular fibers’ attachments to the ciliary muscle, choroid or the other structures of the eye. SETTING: Regional T.I.Eroshevsky Ophthalmic Hospital. State Medical University, Samara, Russian Federation. METHODS: We performed microdissection of human autopsy eyes removing sclera, ciliary body, choroid and retina one after another. Lens capsule, zonular fibers and vitreous membrane were stained by trypan blue. RESULTS: The ciliary processes can be relatively easily detached from the zonular fibers. After the removal of all the external layers the whole vitreal-zonular-lenticular complex was revealed. All the zonular fibers have 3 fixation points: anterior point is at the lens capsule, intermediate points are in the cells of non-pigmented epithelium of the ciliary processes. Posteriorly zonular fibers merge with the vitreous membrane 2 mm before the ora serrata and then sink into the vitreous body. Non-pigmented and pigmented epithelium cells stay relatively firmly attached to the zonular fibers only at intermediate and posterior zonular fixation points. CONCLUSIONS: Vitreous body is the principal posterior fixation of zolula ciliaris. As there is no evidence of direct connection of zonular fibers with either ciliary muscle or choroid, muscular-zonular tension appears to be a subsidiary mechanism of accommodation. The theories of accommodation based solely on muscular traction may require revision.
A. Zolotaryov, E. Karlova, RUSSIA