any structural anomaly of the circumferential suspensory ligaments that anchor the lens to the ciliary process and are made of bundles of fibrillin microfibrils, an elaborate system of fibers that spans the gap between the lens and the adjacent nonpigmented ciliary epithelium; this fibrous rigging ensures lens centration; in species that accommodate, the zonule transmits the forces that flatten the lens, allowing the eye to focus on distant objects