1. Blindness
It is a lack of vision or loss of vision that cannot be corrected with glasses or contact lenses

2. Causes Cataracts ,Glaucoma, Trauma, Trachoma
Macular degeneration, Diabetic retinopathy
Childhood blindness – genetic defects
Onchocerciasis or river blindness caused by parasite filarial worm onchocerca volvulus
Pregnancy related – if mother is having retinopathy and rubella during pregnancy
Optic nerve hypoplasia
Poisoning – methylated spirits – ethanol
Willful actions – torture

3. Systemic diseases
Hypertension – uncontrolled hypertension can cause hemorrhage, edema and exudates in the retina.
Cardiovascular accident – depending of the location of stroke the patient may experience hemianopia or blindness
Sickle cell disease – can cause arterial occlusion or retinal hemorrhage

4. Neurological disorders – multiple sclerosis (demyelination can result in optic neuritis )
Endocrine disorders – diabetic retinopathy
HERPES ZOSTER
Cytomegalovirus
Kaposis sarcoma

5. Types
Absolute blindness or total – defined as no light perception and no usable vision
Functional blindness – some light perception but no usable vision
Preventive blindness – persons with eye disorders which is well treated.
legal blindness
Congenital blindness

6. Rehabilitation of a blind person
Blindness may be present at birth or develop (suddenly or slowly) at any time in an individuals life.
Rehabilitation of a newly blinded person often begins in hospital and continues after the person goes home.

7. Meeting and Greeting
Always ask first before offering any help
Be precise if giving instructions – giving directions by pointing and saying, ‘it is down there on the right’, is not much helpful.
Once into a conversation, never leave without saying. Do not allow the blind person the embarrassment of talking into the air.
Before leaving tell the person who all are there left in the room.

8. Approach and Attitude
Always treat a blind person normally; speak first and introduce yourself
Shake hands but only if a hand is offered
It is also politeness to look at him/her during conversation and adopt the same level of position, e.g., sit or stand
Do not be afraid of using normal language and include words like ‘look’, ‘see’, ‘read’, remembering that blind and visually impaired people have exactly the same vocabulary as sighted people
do not shout
Guiding
Always consider a person's age and any other disabilities
Ask for details of where and how he/she would like to be guided. Go at their place and, if there is space, walk side by side and always ‘hand to arm’

9. If there is a guide dog, but extra help is needed, approach and walk on the other side. The animal has been trained to understand that he is still in charge and responsible.
Give adequate, plenty of time for response if you need to say, “bend your head low to avoid this tree branch.”
Describe any sudden changes in the environment. It is also very important to explain changes in ground surfaces and especially when moving into wide open spaces, e.g., fields.

10. Walking (e.g., in shops, offices and busy crowded areas)
Tell your partner the change in surroundings and then move your own guiding arm towards the middle of your own back
Your partner should automatically step in behind you, still holding your arm, and together you will be able to negotiate a narrow space.

11. Doorways
It is important to take this maneuver (movement) very slowly; it is not an easy one to master
Tell your partner if the door opens towards you or away from you
Go through the door with your partner on the hinge side
Open the door with your guiding arm; your partner should place his/her hand against the door to feel the handle
He/she should then follow you through and close the door behind both of you.

12. Seating
Guide your partner to the seat and explain what type it is – e.g., upright chair, low sofa, armchair, stool
Ask them to let go of your arm and place their hand on the back or the seat of the chair
This is sufficient to help as your partner will now be able to judge the height of the seat and will be able to sit safely and at his/her own pace.

13. Steps, Stairs and Slopes
Tell your partner whether the steps, stairs or slope go up or down. Going down is more difficult.
Allow your partner plenty of time to hold the handrail securely and judge the first step carefully
Go one step ahead and take a slightly longer stride on the last step to allow your partner space

14. Mobility
Now a wide range of tools and techniques are available so that the blind persons can walk independently
Orientation and mobility specialists – they train the blind peoples to get used to these tools
The environment and the route from house to house is also being teach

15. White cane with red tip – the international symbol of blindness
Blind peoples will have identification card
Guide dogs –dogs which specially trained are now a days very helpful. They are specially trained about the environment and the route the person has to go
GPS devices – software can assist blind people with orientation and navigation

16. Reading and magnification
If the person is not completely blind, he can read large print and with the use of magnification devices
Braille language – tactile writing system used by the blind.
Reading machines

17. Other aids and techniques
Talking equipment such as thermometers, watches, clocks, scales, calculators and compasses
Adaptations of coins and bank notes are determined by touch

18. Legal blindness
Defined as visual acuity of 20/200 (6/60) or less in the better eye with best correction possible
This means that a legally blind individual would have to stand 20 feet from an object to see it with corrective lenses with the same degree of clarity as a normally sighted person could from 200 feet.

19. Sports Swimming, snow skiing and athletics
World wide authority on sports for the blind is the international blind sports federation