Tuesday, January 10, 2017

Myopia and its status in Nepal

    
     



Nepal is seeing a high rise in the number of myopia-related cases in recent years. In fact, according to a report published by our Ministry of Health and Population in 2011, there were an estimated 11 million cases of myopia in the country.  According to a report published by the World Health Organization (WHO), there was an  estimated case of  158 million cases of myopia worldwide in 2007. By some estimates, one-third of the world’s population—2.5 billion people—could be affected by shortsightedness by the end of this decade.







What causes Myopia?

Definition:   Myopia (Nearsightedness) is a refractive defect of the eye in which distant object appear blurred because their image are focused in front of the retina rather than on it.
Myopia is the most common refractive error of the eye and is becoming more prevalent. Severe Myopia can lead to other complications such as retinal detachment, eye floaters and macular degeneration.



        

  Our eyes were never designed by evolution for the way we use them today. In order for the eye to focus on close objects, the ciliary muscle tightens and causes the lens of the eye to thicken. Constant focusing on close objects causes a spam on the ciliary muscle, a constant pulling on the sclera and a related pressure increases in the vitreous or large chamber of the eye. As the sclera stretches and becomes larger, the body creates more liquid in the vitreous to fill the increased volume. This is the body’s simple way of refining the vision by reducing the normal farsightedness of the infant. This natural elongation of the eye becomes abnormal when the eye has no farsightedness left and moves into a myopic condition. 



Genetic Causation:

  • More correlated in identical twins than fraternal twins
  • More correlated between parents and children than “by chance”
  • Gene mutations associated with severe Myopia (SCO2)
  • Wide Variation between different ethnic groups
        Asia 70-90%

        Europe/America 30-40%
        Africa 10-20%

Environmental Causation:

  • Large increase among Aboriginal People after Western Schooling 
  • Correlation between Myopia prevalence and academic achievement
  • Experimental demonstration of defocus- induced ocular growth in animals



Diet and Myopia:

  • Some studies implicate contribution to Myopia from
  • Hyperinsulinamia and insulin resistance
  • Excess intake of carbhohydrate and whole grains
  • Deficiency of fish Oil and essential fatty acids
  • Mineral Deficiency (Copper)


How Can Myopia be reversed?

Hormesis:

Hormesis is the beneficial response of an organism to a low dose stressor that is otherwise detrimental or lethal at high dose.

Examples


Exercise                                             Active focusing
Immunization                                    UV radiation
Calorie restriction                              Phytonutrients
Cold exposure                                   Callus formation
Heat Exposure                                   Barefoot running   


Active Focusing techniques

1.Print pushing

For Myopes, this is done by repeatedly pushing a printed page just slightly outside the range of focus, and allowing it to sharpen up or clear. The eye gradually adapts to increase its range. This can be done with different objects at different ranges. So it can be done with fine print close up, but also with larger objects in the distance. It is  especially useful to focus sharp lines, such as overhead electrical  transmission lines, and houses or trees with sharp edges. For Myopes it is best carried out by use plus lenses.

2.Use of plus lenses while reading

3.Progressively weaker lenses

4.Fusing Ghosted Images

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