• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

How to treat Cataracts.

Extracts from this document...




                 Normal Vision                                  Eye with Cataracts

A cataract is a clouding of the natural lens, the part of the eye responsible for focusing light and producing clear, sharp images. The lens is contained in a sealed bag or capsule. As old cells die they become trapped within the capsule. Over time, the cells accumulate causing the lens to cloud, making images look blurred or fuzzy.  The light rays are refracted off their normal path onto the back part of the eye making the objects appear out of focus.



During surgery, a special instrument breaks apart the old Lens with Ultrasound.

...read more.



Extracapsular Surgery

During Extracapsular Surgery, an incision slightly larger than for Phacoemulsification is made in the eye and the Lens Nucleus is removed, leaving the rear Capsule of the lens intact. Leaving the Posterior Capsule reduces the risk of complications later on. The Intraocula Lens is then implanted behind the Iris.


Posterior Chamber Lens Implant

A Posterior Chamber Lens Implant is similar to a contact lens, with one big difference: The Intraocula Lens is an internal and permanent part of the Eye. An Intraocula Lens is placed in the posterior chamber (an area behind the Iris).

...read more.


The Intraocular Lens (IOL) does much the same thing as your old lens did before it become cloudy. It focuses light, letting you see sharply and in vivid color. The IOL Normally lasts a lifetime.


Laser Treatment After Cataract Surgery

Months or years after Cataract Surgery, vision may become blurry again. This is not another Cataract, but the natural Capsule that holds the Intraocula Lens has become cloudy. This cloudy Capsule is called a Secondary Cataract or After Cataract and can be treated quickly and painlessly in the doctor's office with Laser Surgery.


Ben Moore        Physics Assignment        Cataracts

...read more.

This student written piece of work is one of many that can be found in our AS and A Level Microscopes & Lenses section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related AS and A Level Microscopes & Lenses essays

  1. "An investigation into the factors affecting a lens."

    A concave lens does not form any such image, it makes only a "virtual image" which cannot be displayed on a screen as it will be on the same side of the lens as the object. In order to construct a ray diagram, you need to know the focal length

  2. My experiments focus is to obtain an accurate measurement for a specific lenss power.

    It is merely 0.025 Dioptres more than the claimed lens power of 6.7D This is an error of (0.025/6.7)x100 = 0.373%. Theory My experiment focuses on the law that the curvature of a wave front after passing through a lens (1/V)

  1. Proving the lens formula.

    However, I feel checking twice, taking the distances where the image appears focused, and taking a middle value, will give reliable results. Another Variable that could affect the point where the image is focussed is exterior light not emitted from the object (lamp and mesh).

  2. Relationship Between U and V For a Convex Lens

    The virtual image has a negative distance from the lens, which means the image it is virtual. However at 14.9cm the largest distance of v is produced, after which the distance of v decreases. Variables * Independent variable My independent variable is u (object distance).

  1. This essay is on vision, its malfunctions & diagnostics methods.

    A clinical explanation for this may be that the eyeball is shorter in length or the refractive power of the lens is too weak. Correction is achieved by wearing convex lenses which focus the object being viewed onto the retina.

  2. The eye.

    muscles become weaker. A kind of long sight. 3) Astigmatism - caused by uneven curvature of the cornea and or lens. Corrected by cylindrical lens ground to correct shape. 4) Cataracts One or both lenses often become cloudy as one ages.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work