Abstract: the so-called myopia means that in a relaxed state, the distant parallel light cannot fall on the retina right after refraction, but focuses in front of the retina, resulting in unclear vision from a distance.
as we all know, myopia is to see clearly near and blurred far; “Presbyopia” is to see far and clearly and see near blurred. Then, can the degree of myopia be offset after myopia patients suffer from presbyopia?
the principle of myopia is different from presbyopia.
are not unfamiliar with myopia. In recent years, the incidence rate of myopia has been rising rapidly in China. Due to the increase of academic pressure and bad reading habits, many primary school students have been wearing myopic glasses since primary school. The so-called myopia of
refers to that in a relaxed state, the distant parallel light cannot fall right on the retina after refraction, but focuses in front of the retina, resulting in unclear vision from a distance.
at present, the most common cause of myopia around us is the long-term poor reading posture, which makes the refractive muscles in a continuous contraction state to meet the requirements of the eyes to see near objects. Over time, the adjustment ability of seeing far objects is constantly damaged, and the eyeball is also deformed, so it is necessary to wear concave lenses to correct the light received by the eyes, Make it fall right on the retina.
usually refer to presbyopia, which is actually the common name of presbyopia. It refers to the impairment of visual adjustment function caused by the increase of age, the gradual hardening of lens, the weakening of elasticity and the reduction of the relaxation and contraction function of ciliary muscle. In other words, the ciliary muscle of presbyopia patients has weak contraction and can not fully relax the lens. At the same time, the elasticity of the lens is weakened and can not fully rebound, resulting in unclear and unsustainable near objects.
myopia and presbyopia cannot be offset because they are fundamentally different from pathology. Myopia is due to ametropia, while presbyopia is lens degeneration and loss of elasticity. In clinical manifestations, presbyopia in patients with myopia will be slightly lighter than that in ordinary patients, but the degree of “slowing down” is quite limited. Patients with severe myopia and presbyopia should use presbyopia glasses when reading, and use myopia glasses when looking at a distance, which is more inconvenient than ordinary presbyopia patients.
young people suffer from presbyopia, and electronic products are the “culprit”. Before
, there was a saying among the people that “48 is the threshold of presbyopia. However, it is understood that more and more presbyopia patients in their 30s seek medical treatment in the ophthalmology clinics of major hospitals. In addition to some congenital reasons, the main external reason of
lies in the excessive use of electronic products. Foreign medical institutions have found a phenomenon of “smart phone aging”: patients in their 20s have early symptoms of aging such as reduced zoom ability due to long-term use of smart phones and excessive eye fatigue. Most of these young presbyopia patients are white-collar workers and programmers who rely on computers.
presbyopia suddenly becomes better. We need to be vigilant against cataract.
for the middle-aged and elderly people who already have “presbyopia”, if they suddenly read books and newspapers one day, they don’t need to wear glasses. Don’t think it’s “presbyopia” first. It’s best to go to the ophthalmology department to check whether they have cataract. Cataract is the change of refraction after the lens becomes turbid and absorbs water, which is similar to myopia. This change may just offset the degree of “old flower”, so it becomes clearer when you look close. This is actually one of the early symptoms of cataract.
how to prevent presbyopia pay attention to the way of using eyes
for friends engaged in close and fine work, the adjustment load of their eyes is much higher than that of the general population, so they are more likely to have presbyopia symptoms earlier. Therefore, friends with special professional characteristics should pay attention to regular rest and adjustment in their daily work to avoid long-term and continuous eye work.
01. Outdoor activities rotate the eyes
use opening and closing the eyes to excite the eye muscles, rotate the eyes up, down, left and right, rotate clockwise and counterclockwise, improve the blood circulation of eye muscles and delay aging.
02. Keep sufficient light in the working environment.
sufficient light during reading increases the contrast between words and books, makes the font easier to see and reduces the adjustment burden on the eyes. In addition, sufficient light can narrow the pupil, increase the depth of field and improve vision, so as to help patients with presbyopia improve their reading ability.