Cataract – Lens Replacement – Glaucoma – Nyctalopia

Cataract

Cataract is the opacity in the lens of the eye. The normal lens allows
light to reach the retina when it becomes opaque and does not allow light to
reach the retina, the person is unable to see clearly. Cataract is due to
(coagulation) changes in the delicate protein fibres within the lens, cataract
never causes complete blindness but causes increased loss of transparency.
The clarity and the detail of the image is progressively lost. The front part of
the lens becomes densely opaque and whiteness is visible in the pupil.
The causes for cataract formation in the adult is related to aging, sun
light exposure, smoking, poor nutrition, eye trauma, systematic diseases like
diabetes mellitus, infection and injuries and certain medications such as
steroids. Sometimes German measles in pregnant mothers causes cataract in
the child.

To delay the onset of cataract one should have nourishing diet,
protect eye from excessive exposure to sun rays, X-rays, intense heat and
injuries. Diseases like diabetes and syphilis should be treated early and
effectively.

Two types of cataracts are dense nuclear cataract (cataract in the
center of the lens) and Peripheral cataract (cataract in the periphery of the
lens). There is no medical treatment for cataract. The only treatment is
surgery. Once the cataract is removed, the eye is unable to focus, as there is
no lens. So one has to use an artificial lens. This can either be glasses,
contact lenses or insertion of introcular lenses.

Today modern medical advances have made cataract surgery very
successful. New surgical techniques and intracular lenses can restore
excellent vision (97%).

Lens Replacement

For individuals who are over 40 years of age, considering refractive
surgery to decrease dependence on glasses and contact lenses, Clear Lens
Replacement (CLR) is an exciting option. In essence, this procedure entails
removing the natural lens of the eye and replacing it with an intraocular lens
(IOL) implant.

CLR may be an excellent alternative to these procedures for people
already wearing bifocals since CLR requires removal of the natural lens of
the eye, the patient is subsequently unable to focus (accommodate) at near
by objects . This is why CLR is best suited for patients over 40 who are
already wearing bifocals. One potential solution to this problem of
accommodative loss is implantation of the multifocal IOL (Intra Occular Lens)
implant. This implant allows focusing at both near and far objects.

Glaucoma

Glaucoma is a serious disorder of the eye and is a common cause of
blindness. Increased IOP (Increased Occular Pressure) compresses the
optic nerve at the optic disc with degeneration of optic nerve fibres and
cupping of the optic discs with progressive loss of visual acuity starting with
peripheral vision. The retinal artery which enters the eye ball at the optic disc is compressed causing retinal degeneration. In most cases the cause of
glaucoma is unknown but in some cases it may be due to infection or trauma
in the eye. When the IOP is very high (50-70 mm Hg) blindness occurs
within few days.

Nyctalopia

Vitamin A is necessary for resynthesis of visual purple. Nyctalopia
or night blindness is the first sign of vitamin A deficiency. Prolonged
deficiency of vitamin. A leads to degenerative changes in rods and cones and
nervous layers of the retina. Administration of vitamin A before degenerative
changes occur will restore retinal functions. Normal retinal function also
requires the presence of optimal amounts of other vitamins especially the B
complex just as other nerve tissues do.

Cataract – Lens Replacement – Glaucoma – Nyctalopia

Cataract

Lens Replacement

Glaucoma

Nyctalopia

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