Theory:

Some of the diseases that affect the eyes and their remedial measures are as given below:
Night blindness:
nightblindnessjpgw400.jpg
Deficiency in Vitamin A causes night blindness
  
Causes:
It is mainly due to the lack of vitamin A and disorder of the cells in the retina.
 
Impacts/consequences:
It causes difficulty in vision during the night or in poor light.
 
Measures to be taken:
In order to avoid this foods that are rich in anti-oxidants, vitamins and minerals are to be taken.
Conjunctivitis:
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Conjuctivitis or pink eye
  
Causes:
It is caused due to a virus and bacteria.
 
Impacts/consequences:
Either one or both the eyes are affected. It is a highly contagious disease that can be spread by contamination and sneezing.
 
Measures to be taken:
By using antibiotic eye drops or ointments and following certain home remedies.
Colour blindness:
Red_to_Green_Color_Blindness.png
Different types of colour blindness
  
Causes:
It is a genetic condition.
 
Impacts/consequences:
During this condition the person is unable to distinguish between colours and the different shades or tones of the same colour cannot be seen.
 
Measures to be taken:
A known cure for this disease is unavailable. Contact lenses and glasses with filters can be used for this disease.
Reference:
https://www.vecteezy.com/vector-art/454844-viral-conjuctivitis-in-human-eyes
https://commons.wikimedia.org/wiki/File:Red_to_Green_Color_Blindness.png