Ciliary zonule

The portion in front of the ora serrata is thickened by the accession of radial fibers and is termed the zonula ciliaris(zonule of Zinn).

Here it presents a series of radially arranged furrows, in which the ciliary processes are accommodated and to which they adhere, as is shown by the fact that when they are removed some of their pigment remains attached to the zonula. The zonula ciliaris splits into two layers, one of which is thin and lines the hyaloid fossa and a thicker layer, which is a collection of zonular fibers. Together, the fibers are known as the suspensory ligament of the lens: it is thicker, and passes over the ciliary body to be attached to the capsule of the lens a short distance in front of its equator. Scattered and delicate fibers are also attached to the region of the equator itself. This ligament retains the lens in position, and is relaxed by the contraction of the meridional fibers of the Ciliaris muscle, so that the lens is allowed to become more convex. Behind the suspensory ligament there is a sacculated canal, the spatia zonularis (canal of Petit), which encircles the equator of the lens; it can be easily inflated through a fine blowpipe inserted under the suspensory ligament.