PRESENTATION OF EYE

SUBMITTED TO:- HARPREET MA`AM

Understanding Vision

The cornea & lens work together to focus images in the eye

Distance Vision

Cornea

LensLens

FocalPointFocalPoint

The Human Eye = The Camera

Parts Of Eyes

CorneaThe cornea is a clear, dome-shaped surface that covers the front of the eye. It is the first and most powerful lens in the eye's optical system. To keep it transparent the cornea contains no blood vessels. Tears that flow over it and aqueous humor in the chamber behind it keep it nourished. When you hear of eye banks and eye transplants, it is the cornea that is being replaced. The cornea can be damaged from: accidents, infections, and genetic defects.

Pupil The pupil is the hole in the center of the iris that light passes

through. The iris muscles control its size.

Retina The retina is the film of the eye. It converts

light rays into electrical signals and sends them to the brain through the optic nerve. The sides of the retina are responsible for our peripheral vision. The center area, called the macula, is used for our fine central vision and color vision. The retina is where most the problems leading to vision loss Occur. Three of the leading causes of blindness, from retina damage, are Retinitis Pigmentosa, Macular Degeneration and Diabetic Retinopathy.

Iris This is the colored part of the eye:

brown, green, blue, etc. It is a ring of muscle fibers located behind the cornea and in front of the lens. It contracts and expands, opening and closing the pupil, in response to the brightness of surrounding light. Just as the aperture in a camera protects the film from over exposure, the iris of the eye helps protect the sensitive retina.

Sclera

The sclera is the white, tough wall of the eye. It along with internal fluid pressure keeps the eyes shape and protects its delicate internal parts.

ciliary body (muscles)

*circular muscle that surrounds the edge of the lend* connected to the lens by suspensory ligaments*changes the shape of the lens

The blind spots in each eye are aligned symmetrically so that most of the time, one eye’s field of vision will compensate for the loss of vision in the other. The diagram above shows where the blind spots are located.

DIESEAS OF EYE Some eye problems are minor and fleeting. But some

lead to a permanent loss of vision. Common eye problems include,Cataracts - clouded lenses

Glaucoma - damage to the optic nerve from too much pressure in the eye.Retinal disorders - problems with the nerve layer at the back of the eye.Conjunctivitis - an infection also known as pinkeye.

Your best defense is to have regular checkups, because eye diseases do not always have symptoms. Early detection and treatment could prevent vision loss. See an eye care professional right away if you have a sudden change in vision or everything looks dim or if you see flashes of light. Other symptoms that need quick attention are pain, double vision, fluid coming from the eye and inflammation.

Cataract

A cataract is a clouding of the lens in your eye. It affects your vision. Cataracts are very common in older people. By age 80, more than half of all people in the United States either have a cataract or have had cataract surgery.

Common symptoms are Blurry vision Colors that seem faded Glare Not being able to see well at night Double vision Frequent prescription changes in your eye wear Cataracts usually develop slowly. New glasses, brighter

lighting, anti-glare sunglasses or magnifying lenses can help at first. Surgery is also an option. It involves removing the cloudy lens and replacing it with an artificial lens. Wearing sunglasses and a hat with a brim to block ultraviolet sunlight may help to delay cataracts.

Retinal Disorders The retina is a layer of tissue in the back of your

eye that senses light and sends images to your brain. In the center of this nerve tissue is the macula. It provides the sharp, central vision needed for reading, driving and seeing fine detail.

Retinal disorders affect this vital tissue. They can affect your vision, and some can be serious enough to cause blindness. Examples are

Retinal detachment - a medical emergency, when the retina is pulled away from the back of the eye

Macular pucker - scar tissue on the macula Macular hole - a small break in the macula that

usually happens to people over 60 Floaters - cobwebs or specks in your field of vision

Glaucoma  Glaucoma damages the eye's optic nerve.

It usually happens when the fluid pressure inside the eyes slowly rises, damaging the optic nerve. Often there are no symptoms at first, but a comprehensive eye exam can detect it.

People at risk should get eye exams at least every two years.

Early treatment can help protect your eyes against vision loss. Treatments usually include prescription eyedrops and/or surgery.

 

Conjunctivitis is the medical name for pinkeye. It can cause swelling, itching, burning, discharge and redness of the protective membrane that lines the eyelids and covers exposed areas of the white of the eye. Causes include

Bacterial or viral infection Allergies Substances that cause irritation Contact lens products, eye drops, or eye

ointments Pinkeye usually does not affect vision. Infectious

pink eye can easily spread from one person to another. The infection will clear in most cases without medical care, but bacterial pinkeye needs treatment with antibiotic eye drops or ointment.

Pink eye

MADE BY :-

Tejus sahi

Hardik Gupta

S H U B H A M

KAMAL

ARPIT

Have A Nice Day