Zonule

Zonule of Zinn (also known as Zonule fibers or Suspensory ligaments of the lens) are a series of fibers connecting the ciliary body with the crystalline lens of the eye. These fibers are responsible for holding the lens in place.

Anatomy

The zonule of Zinn is split into two layers: the anterior layer and the posterior layer. The anterior layer extends from the ciliary processes to the lens equator, while the posterior layer extends from the ciliary processes to the posterior pole of the lens. The zonule of Zinn is primarily composed of fibrillin and elastin, which provide the fibers with their elasticity and resilience.

Function

The primary function of the zonule of Zinn is to hold the lens in place within the eye. However, they also play a crucial role in the process of accommodation, which is the ability of the eye to adjust its focus from distant to near objects. The tension of the zonule fibers can change, allowing the lens to alter its shape and thus change the focal point of the eye.

Clinical significance

Damage or degeneration of the zonule of Zinn can lead to a number of eye conditions. For example, in Marfan syndrome, a genetic disorder affecting connective tissue, the zonule fibers can become weakened, leading to lens dislocation. Similarly, in pseudoexfoliation syndrome, abnormal protein fibers can accumulate on the zonule, potentially leading to glaucoma.

See also

• Ciliary body
• Crystalline lens
• Accommodation (eye)
• Marfan syndrome
• Pseudoexfoliation syndrome