What Is Zonular Fibers Of The Eye?

Zonular fibers do not project from the innermost tips of the ciliary epithelium but rather originate in the posterior pars plicata region (C).

What is the function of the zonular fibers?

The zonule is essentially a system of numerous fibers that run from the ciliary body to the lens periphery, whose function is both securing the lens in the optical axis and transferring forces from the ciliary muscle in accommodation.

Where do lens zonules originate?

The zonular filaments originated in the nonpigmented epithelium of the ciliary process and, on the extending pathway in the chamber toward the lens capsule, filaments assembled with the neighboring filaments, forming bundles of various sizes (Aa).

Where is ciliary muscle?

The ciliary muscle is elongated, triangular in shape, and located beneath the anterior sclera just posterior to the limbus. The shortest side of the triangular region faces anterior-inward and it is to this region of the ciliary body that the base of the iris inserts.

What are zonules made of?

The Zonules (of Zinn) are a ring of fibrous strands, composed mainly of elastin microfibrils, that extend from the cilary body to the equator of the lens capsule and thus suspending the lens in place.

What are the Zonular fibers attach to?

The zonular fibers anchor the the equator of the lens and adjacent anterior and posterior surface of the lens to the ciliary body and and ciliary part of the retina. The ciliary epithelial cells of the eye probably synthesize portions of the zonules.

Is Zonular fiber elastic?

ZF, are the essential part of the suspensory system of the lens. ZF are transparent and elastic. They form a circular and spindly structure between the ciliary body and the equatorial circumference of the lens capsule (Fig.

What is the meaning of zonules?

/ (ˈzɒnjuːl) / noun. a small zone, band, or area.

Which part of the eye constricts in bright light?

In bright light, the iris closes (or constricts) and makes the pupil opening smaller to restrict the amount of light that enters your eye.

Where is the posterior chamber in the eye?

Posterior chamber: The posterior chamber is between the iris and lens. The lens is behind the iris and is normally clear. Light passes through the pupil to the lens. The lens is held in place by small tissue strands or fibres (zonules) extending from the inner wall of the eye.

What is Zonular dehiscence?

Definition. Rupture of the fibrous strands connecting the ciliary body and the crystalline lens of the eye. [

What is subluxation of lens?

In lens subluxation, zonular fibers are broken, and the lens is no longer held securely in place but remains in the pupillary aperture. Lens dislocation occurs following complete disruption of the zonular fibers and displacement of the lens from the pupil. Trauma is the leading cause of lens dislocation.

What is zonular weakness?

Zonular weakness can be caused by disease or trauma, and its presence can make cataract surgery more challenging. Fortunately, there are adjunctive devices to effectively manage it and achieve successful outcomes. Causes. Certain diseases of the eye are associated with zonular weakness or insufficiency.

Where is vitreous humor produced?

The vitreous humor is a clear body fluid found within the eyeball. It is the major body fluid in the eyeball (another body fluid is the aqueous humor). It is produced by the non-pigmented cells in the ciliary body.

What is the cornea part of?

The cornea is the transparent part of the eye that covers the front portion of the eye. It covers the pupil (the opening at the center of the eye), iris (the colored part of the eye), and anterior chamber (the fluid-filled inside of the eye).

What is the function of the ciliary body in the eye?

The ciliary body is found behind the iris and includes the ring-shaped muscle that changes the shape of the lens when the eye focuses. It also makes the clear fluid that fills the space between the cornea and the iris.

What is ora serrata in human eye?

Peripheral Retina

The ora serrata is the peripheral termination of the retina and lies approximately 5 mm anterior to the equator of the eye. … The ora serrata is approximately 2 mm wide and is the site of transition from the complex, multilayered neural retina to the single, nonpigmented layer of ciliary epithelium.

What is iris eye?

The colored tissue at the front of the eye that contains the pupil in the center. The iris helps control the size of the pupil to let more or less light into the eye.

What is the function of aqueous humor?

Aqueous humor – the clear, watery fluid between the cornea and the front of the vitreous. The aqueous humor bathes and nourishes the lens and maintains pressure within the eye. Since the lens and cornea have no blood supply, the aqueous humor performs the blood’s job of carrying nutrients to those structures.

What is Zonulopathy?

Zonulopathy is a condition characterized by a lack of zonular support for the lens capsule due to zonular weakness or dialysis. This condition may encompass subluxation or dislocation of the lens.

What are Zonular Fibres collectively known as?

These fibers are sometimes collectively referred to as the suspensory ligaments of the lens, as they act like suspensory ligaments.

Where is the region associated with maximum visual acuity?

The fovea centralis is part of the retina. There are only cone cells in the fovea centralis. It is the site for maximal visual acuity.

What happens when ciliary muscle contracts?

When the ciliary muscle contracts, it pulls itself forward and moves the frontal region toward the axis of the eye. This releases the tension on the lens caused by the zonular fibers (fibers that hold or flatten the lens).