Disease of Eye | Blindness

Signs and Symptoms of Blindness

People who are blind or have visible disability have the common sign of difficulty viewing. People who have similar stages of visual shortage may have very different responses with that symptom. In case a person is born blind, there is much less adjustment to a non seeing entire world compared to there is for those who lose their eyesight late in life, where there may be small capability to cope with that visual loss. Support systems available to human beings and their psychological make-up will even change the symptom of lack of sight. Those who lose their vision suddenly, rather than during a period of years, also can have more difficulty adjusting to their visual loss.

Associated signs and symptoms, such a discomfort in the eyes, awareness of the eyes, foreign body sensation, and ache in the eyes or discharge from the eyes may be present or absent, based on the underlying cause of the blindness.

A blind one may have no noticeable symptoms of any abnormalities when sitting in a chair and resting. However, when blindness is the result of an infection of the cornea, generally transparent cornea may become white or gray, making it hard to see the coloured portion of the eye. In blindness from cataract, the generally black pupil may appear white. Based on the degree of blindness, the affected individual will exhibit signs of visual loss when attempting to ambulate. Few blind persons have learned to look directly at the person they are talking with, therefore it is not obvious they are blind.

Causes of Blindness

The following eye diseases and conditions can create blindness:

• Glaucoma develops when the strain of the eye is enhanced and that brings about progressive loss of sight. It is essential to recognize and treat glaucoma as the vision lost is irreversible.
• Macular degeneration damages the portion of the eye that enables you to see details. It generally impacts older adults.
• Cataracts lead to cloudy vision. They’re more usual in seniors.
• Lazy eye makes it complicated to see details. It may bring about vision loss. Amblyopia is normally known as a “lazy eye”.
• Optic neuritis is inflammation which causes temporary or permanent vision loss.
• Retinitis pigmentosa means damage of the retina. It brings about blindness only in rare cases.
• Tumors that impact the retina or optic nerve can also result in blindness. 
• Blindness is a possible complication when you have diabetes or have a stroke.
• Birth defects, eye injuries, and complications from eye surgery are some other typical reasons for blindness.

Who is at Risk of Blindness

The following categories of persons are at risk of blindness: 

• People who have eye diseases, for example macular degeneration and glaucoma 
• People suffering from diabetes 
• Anyone who has a stroke 
• Eye surgery victims 
• Individuals who work with or close to sharp objects or toxic chemicals
• Premature babies 

Diagnosis of Blindness

There are basically two major areas that are looked at when someone’s vision is measured:

Visual Acuity: It is central vision and is familiar to look at objects in detail, for example reading a book or watching video.

Visual Field: It is the capability to see around the edge of vision while looking straight ahead.

Visual Field Testing:

During visual field testing one will be directed to look straight ahead at a machine while lights are flashed on and off in peripheral vision . Person will be asked to press a button each time you see a light. This shows any gaps in his area of vision.

Test for Visual Acuity:

A snellen chart is utilized to determine visual acuity. It relates to reading letters off a chart on which the letters turn into progressively smaller sized. This chart is used during a routine eye test. After the test, a score made up of two numbers is given. The first number shows the distance far from the chart were able to successfully read the letters on the chart. The second number shows the distance away a person with healthy vision should be able to read the chart.

So if you were given a visual acuity score of 6/60, this means you can only look at 6 meters away what a person with healthy eyesight can read 60 meters away. The normal eyesight is 6/6.

Partial sight impairment:

Partial sight, or sight impairment, is usually defined as:

• Having very poor visible acuity ( 3/60 to 6/60 ) but having a full field of vision. 
• Having a combination of moderate visual acuity ( up to 6/24 ) and a decreased field of vision or having blurriness or cloudiness in the central vision. 
• Having relatively good visual acuity ( up to 6/18 ) but a lot of your field of vision is losing. 

Severe sight impairment (Blindness)

The legal meaning of severe eyesight impairment ( blindness ) is when ‘a individual is so blind that they cannot do any work for which eye-sight is essential’.

This normally falls into one of three categories:

• Having extremely poor visual acuity ( lower than 3/60 ) but having the full field of vision
• Having inadequate visual acuity ( between 3/60 and 6/60 ) and a severe decrease in in the field of vision
• Having average visual acuity ( 6/60 or better ) and an extremely lowered field of vision 

Treatment of Blindness

A few of the medical treatment possibilities and the surgical treatment possibilities which are used to correct vision defects and reduce loss include :

Conjunctivitis:

• Cleaning of the eyes 
• Antibiotic droplets similar to chloramphenicol 
• Using of dark goggles

Glaucoma

• Medical line of treatment-eye droplets & pills . 
• Surgical 

Corneal Ulcer 

• Using eye drops. It is actually depend upon kind of ulcer 
• Use of dark goggles 
• Cleaning of eyes
• Rest to the sight by mydriatics

Iritis

Local Steroid eye drops and ointments, cycloplegics, systemic steroids, ocular anti-hypertensive tablets. 

Cataract 
Surgery

Refractive Errors 
Providing Spectacles 

Trachoma 
Tetracycline/Erythromycin eye ointment .

Retinopathy 
Treatment of complication, control of diabetes & hypertension. 

Squint 
Surgery, correction of refraction

Night Blindness 
Treatment with vitamin A

Corneal Opacity 
Surgery