An inflammation of the tissue lining the inside of the eyelid is called Conjunctivitis. Conjunctivitis is also referred to as "pink eye," which is very common and treatable eye infection. Its symptoms include redness of the inner eyelid or white of the eye, increased tear flow, yellow eye discharge and itchy, burning eyes. Highly contagious, conjunctivitis is typically treated with prescription antibiotics dispensed in eye-drop form.

More commonly known as "pink eye", conjunctivitis is an eye infection that can be highly contagious. It causes the conjunctiva, the thin transparent layer covering the inner eyelid and the white part of the eye, to become inflamed, irritated and red

Symptoms of Conjunctivitis

Conjunctivitis symptoms depend on the factors that cause the condition. In general, conjunctivitis symptoms may involve:

• Redness in the white area of the eye
• Redness in the inner layer of the eyelid
• Thick yellowish pus-like discharge
• Itchy eyes
• Eye inflammation
• Blurred vision
• Heightened sensitivity to light

If you are suffering from the symptoms mentioned above, it is the time you should seek help from your health care support. The health care practitioner will organize few eye tests to determine whether you are suffering from conjunctivitis and if so, then the type and severity of the condition, so that an effective treatment procedure can be administered.

Causes of Conjunctivitis
Conjunctivitis occurs most commonly in children, though it can occur at any age. There are generally four types of conjunctivitis:

• viral -- which accompanies a cold or other viral infection
• bacterial -- such as from strep, staph or other bacterial infections
• allergic -- an allergy to dust, molds, pets, cosmetics and other potential irritants
• ophthalmia neonatorum -- a form of conjunctivitis found only in newborns

Other possible causes of conjunctivitis include a partially blocked tear duct, unsanitary environments, and working with intense light.

Stye is a lump or pimple on the edge of the eyelid caused by an infection or inflammation involving the hair follicles of the eyelashes. It most often occurs on the edge of the upper lid, but may also occur on the lower lid. An internal hordeolum is the same as a stye, but involves an internal eyelid gland located further back on the eyelid. A stye can be painful and affect the entire eyelid.

The cause of a stye is a staphylococcus bacterial infection, usually developing near the follicle of an eyelash. Sties may evolve due to:

• poor hygiene
• dirty contacts
• chronic blepharitis
• out of date cosmetics
• leaving eye makeup on overnight
• unwashed hands touching/rubbing eyes

A stye is a painful, tender, red, swollen, pus filled lump or bump at the rim of your eyelid, or eyelash line. It is not a pimple, so don’t try to pop or squeeze the pus out it. Rather, your stye pain relief treatment is the application of a warm compress, laid over your eyelid, 10 minutes, 4 times daily.

Most sties are harmless, without affecting your vision. However, a doctor visit may be necessary if your stye creates issues like:

• vision interference
• frequent, successive infections
• doesn’t spontaneously disappear
• no response to warm compress care
• redness/swelling extends into face/cheek

Refrain from wearing makeup, especially eye liner, until your infection has cleared.

The best treatment for a stye is to apply hot, moist compresses to the eyelid on a frequent basis. This relieves pain and inflammation and helps speed up the formation of a white-head. Once the stye comes to a head, it should drain on its own. However, if it does not empty on its own, surgical draining may be required. The head of the stye is usually on the outside, but it can occur on the underside of the lid. Antibiotic ointment or cortisone drops may be prescribed to keep down the bacteria count of the eyelid. If the tissues surrounding the stye appear swollen and infected, oral antibiotics may also be prescribed.

Although styes are infectious, they are not contagious. It is important not to spread the infection and to practice careful personal hygiene. Do not share washcloths and hand towels, and avoid close personal contact during the acute phase of the disease. If you get sties frequently, see your eye doctor for an examination.

Blindness is the condition of lacking visual perception due to physiological or neurological factors.

Various scales have been developed to explain the extent of vision loss and describe "blindness." Total blindness is the complete lack of form and visual light perception and is clinically recorded as "NLP," a short form for "no light perception." Blindness is often used to describe severe visual impairment with residual vision. Those described as having only "light perception" have no more sight than the ability to tell light from dark. A person with only "light projection" can tell the general direction of a light source.

In order to decide which people may need special help as of their visual disabilities, various governmental jurisdictions have formulated more complex definitions referred to as legal blindness.

Color blindness, a color vision shortage in animals, is the powerlessness to recognize differences between some of the colors that other people can distinguish. It is mainly frequently of genetic nature, however might too happen since of eye, nerve, or brain damage, or due to exposure to sure chemicals. Deuteranopia this term is used for a form of color blindness.
 
Color blindness is frequently classed as disability; though, in chosen situations color blind people have a benefit over people with normal color vision. There are some studies which conclude that color blind individuals are enhanced at penetrating certain camouflages.

Abnormalities such as optic nerve hypoplasia affect the nerve bundle that sends signals from the eye to the back of the brain, which can lead to decreased visual perception.

People with injuries to the brain can, in spite of having unspoiled eyes and optic nerves, still be officially or entirely blind.

Hereditary defects -

People with albinism frequently undergo from visual injury to the extent that many are legally blind, although few of them actually cannot see. Leber's congenital amaurosis is able to reason complete blindness or harsh sight loss from birth or early childhood.
Modern advances in mapping of the human genome have identified other genetic cause of low vision or blindness.

There is usually no treatment to cure color deficiencies. On the other hand, certain types of tinted filters and contact lenses might help out an individual to differentiate different colors.

Strabismus is the misalignment of the eyes. People with this affliction are commonly referred to as "cross-eyed." Either or both eyes may be turned in, up, down or out. It is most often diagnosed in children. Strabismus can be either a disorder of the brain coordinating the eyes or a disorder of one or more muscles, as in any process that causes a dysfunction of the usual direction and power of the muscle or muscles.

The two types of strabismus are -
1. Exotropia
2. Esotropia

1. Exotropia –
People with exotropia often experience crossed diplopia. Intermittent exotropia is a fairly a common condition. "Sensory exotropia" occurs in the presence of poor vision. Infantile exotropia is know as "congenital exotropia".It is seen during the first year of life, and is less common than "essential exotropia" which frequently becomes apparent a number of years afterward.

2. Esotropia -
Esotropia is sometimes speciously called "lazy eye", which describes the condition of Amblyopia. Amblyopia is a reduction in vision of one or both eyes which is not the result of any pathological lesion of the visual pathway and which cannot be resolved by the use of corrective lenses. It is the opposite of Exotropia.Amblyopia can, yet, arise as a result of esotropia occurring in childhood. In order to relieve symptoms of diplopia or double vision, the child's brain will ignore or "suppress" the image from the esotropic eye, which when allowed continuing untreated will lead to the development of amblyopia. Treatment options for esotropia include glasses to correct refractive errors (see accommodative esotropia below), the use of prisms and/or orthoptic exercises and/or eye muscle surgery.

The four types of Esotropia are -

1. Congenital Esotropia.
2. Infantile Esotropia.
3. Accommodative Esotropia.
4. Partially Accommodative Esotropia.

1. Congenital Esotropia - Congenital" means from birth and, using this strict definition, most infants are born with eyes that are not aligned at birth. Only 23% of infants are born with straight eyes. In the common of cases, one eye or the other in fact turns outward during the neonatal period. Within the first three months the eyes slowly come into more consistent alignment as coordination of the two eyes together as a team develops.
2. Infantile Esotropia - The baby with infantile esotropia typically cross fixates, which means that he or she uses either eye to look in the opposite direction. The right eye is used to look toward the left side, and the left eye is used to look toward the right side. By definition, they alternate which eye they are looking with. It is more difficult to help this type of strabismus with non-surgical methods, such as vision therapy and/or glasses.
3. Accommodative Esotropia -
If excessive inward turning of an eye is first noted around 2 years of age, it may be due to difficulty in integrating the focusing (accommodative) system with the eye alignment (binocular) system. Normally when we look across the room or beyond, our eyes are parallel, or straight. However, when we look at things up close, two things happen. We need to converge more (aim both eyes inward at the same time) and we have to input more focus, or accommodate to keep things clear. Children have large amounts of focusing power, and sometimes in getting things clear, inward turning or esotropia results. If the inward turning only occurs up close, as when playing with small objects, making eye contact, coloring, looking at picture books and so forth, the child may just need glasses for near activities to reduce or eliminate the esotropia.
4. Partially Accommodative Esotropia -In some instances, part of the inward turn is due to basic esotropia, and an additional amount due to the effect of accommodation. Glasses may reduce the amount of eye turn, but it is not totally compensated. Initially, the eye doctor may prescribe prism to compensate for the amount of turn. Office-based vision therapy is usually needed. Surgery remains an option to address the non-accommodative portion of the esotropia