Zonular fibres (suspensory ligament of the lens)

Fibrae zonulares

Sensory (eye & ear)OrgansHeadLeft and right

View left in 3D View right in 3D

What it is

Hundreds of fine, transparent fibrillin threads running from the ciliary processes and pars plana to the capsule in front of, at, and behind the lens equator.

Function

Hold the lens centred behind the pupil and transmit the pull of the ciliary body: taut zonules flatten the lens for distance vision.

Size

Each fibre 5-30 micrometres thick; the zonular gap spans ~0.5-2 mm.

Clinical note

In Marfan syndrome (fibrillin defect) the zonules are weak and the lens often dislocates upward (ectopia lentis).