Quick Facts
The zonular fibers are the fibers that anchor the lens capsule to the ciliary body and the ciliary part of the retina (Dorland, 2011).
Related parts of the anatomy
Structure and/or Key Feature(s)
The zonular fibers are a series of fine (1–2 µm diameter) fibers that attach to the margin of the lens. The zonular fibers arise from the orbicularis ciliaris (ciliary ring or pars plana) of the ciliary body and extend to the lens in an anterior, posterior, and equatorial grouping. This arrangement of dense fibers forms the suspensory ligament of the lens (ciliary zonules or zonules of Zinn).
Anatomical Relations
Zonular fibers pass across the aqueous humor of the posterior chamber, though the posterior-most fibers are abutted posteriorly to the vitreous body. The anterior-most fibers are separated by a short space from the posterior surface of the iris.
Function
The zonular fibers suspend the lens from the ciliary body where it sits immediately behind the iris. It transmits forces produced by contraction of the ciliary muscle to the lens, resulting in the lens changing shape, allowing the eye to focus on distant objects (accommodation).
References
Dorland, W. (2011) Dorland's Illustrated Medical Dictionary. 32nd edn. Philadelphia, USA: Elsevier Saunders.
