Fatigue, redness, eye tiredness but also burning, tearing and difficulty reading closely. If you experience these sensations, it is likely that you are experiencing the first symptoms of presbyopia, the typical visual disorder of advancing age due to aging and hardening of the lens inside the eye, called the crystalline, which causes the onset of a progressive difficulty in reading (among other activities) especially in poor lighting conditions or tiredness.
Presbyopia usually begins around age 40 and progresses up to age 60-65 in the eye that has no other visual disturbances. What are the causes that lead to the strain of nearsighted vision?
The crystalline
As underlined by the IAPB, the lens is positioned between the iris and the vitreous body and strongly anchored to the ciliary body by means of ligaments: it is in suspension and is “automatically” deformed to adjust the focus.
It is a structure that is not equipped with nerves or blood or lymphatic vessels (therefore the aqueous humor provides its nutrition). The light that passes through the cornea and the pupil passes right through the lens.
The latter therefore works like a biconvex lens (because it has both curved faces) which converges the light rays coming from the external environment directly on the retina, allowing a clear and sharp vision when the focus is optimal. However, around the age of 40 the lens gradually loses the ability to focus on objects at different distances causing a decrease in accommodative capacity. We can therefore state that the main cause of presbyopia is the loss of elasticity of the lens due to age, which makes it difficult to focus closely.
The accommodation of the eye
SOI, the Italian Ophthalmological Society, defines accommodation as “the mechanism through which the eye is able to focus on objects placed at different distances“. Accommodation, therefore, plays a fundamental role in normal visual functioning.
However, this mechanism loses its capabilities over the years, causing many eye problems. In fact, with the physiological advance of age, the fibers of the ciliary muscle stiffen as well as the crystalline, leading to an effective reduction in the accommodating capacity of the eyes and this is why it becomes difficult to see objects placed at different distances.
We are faced, finally, with natural causes related to presbyopia. Is it possible to correct presbyopia? Surely presbyopia cannot be prevented, because it is a natural and physiological aging process due to the passage of time that potentially affects all of us, none excluded. To learn more about the topic, we recommend reading the article “Correcting presbyopia: all the solutions” on our blog.