Eye fatigue or asthenopia is caused by uncorrected timely violations that occur in the eye unit usually after intense visual work at close range. The main symptoms are eyestrain stinging foreign body sensation and sand in the eyes, fatigue double vision periodic blurred vision headache eye strain. As a result, there is a strong tension of intra-muscle contraction and relaxation which changes the shape of the eye lens and thus allows a person to see well at different distances.
Muscular asthenopia develops as a result of over voltage of the eye muscles which are attached to the outside of the eyeball and provide eye movement. In the absence of correction of the myopia work at close range is possible without the tension of the ciliary muscle, but with the required information in both eyes when working at close range the so-called convergence, which is provided by the voltage of the eye muscles. Normally when working in close proximity ciliary muscle is strained, resulting in changing the shape of the lens and the retina is formed a clear image of close objects.However, vision requires that each eye during near visual work received the same clear image that is achieved just by convergence. When myopia due to a mismatch between the ciliary muscle relaxation and tension of the eye muscles and eyestrain symptoms appears. When treatment is given an early optical correction of myopia.
It is the result of the common diseases of the body infectious diseases intoxications mental and physical strain the wrong mode of work and rest. The range of therapeutic measures includes treatment of common diseases of the body restorative activities a vitamin a rational mode of work and rest.