What is blurred vision?
Blurred vision is a visual disorder in which there is a change in optical perception. The affected person is no longer able to see sharply and, depending on the degree of the visual disorder, only recognizes the contours and shapes of the object he or she has fixed. Blurred vision can occur when looking into the distance or when looking close up. However, there may also be a general lack of visual clarity, which affects all visual settings. The various causes of reduced visual acuity are listed below.
Causes
In order to see an object or its surroundings sharply, an interaction of different eye muscles is necessary. The outer eye muscles, which run around the eye, are responsible for the movement of the eye. Muscles of the eyelid are responsible for opening and closing it, as it happens with every blink of the eye, but also with the active squeezing of the eye.
In addition, there are inner eye muscles that are not controlled arbitrarily by us and which regulate the dilation and constriction of the pupil as well as the adjustment of the eye lens. All these muscle-controlled components play an important role in sharp vision. In order to be able to fix an object clearly, the eyes must be in the correct position.
The pupil limits the incidence of light, and only by adjusting the lens curvature to the distance of the object is it possible to see clearly. Like any other muscle, the eye muscles can be tense. These tensions can be caused, for example, when the affected person’s gaze is very rigid over a long period of time, for example when looking at a screen in the same eye position for a long time.
Tension from other muscle regions such as the forehead, jaw or neck can also be transferred to the eye muscles. Since these muscle regions are located in the immediate vicinity of the eyes and are closely connected to the eye muscles, immobility and thus tension in these muscles also affects their surroundings. can best be relieved by using the following methods LASIK stands for laser in situ keratomileusis.
This is an eye operation that is intended to restore normal vision. In this operation, the cornea is opened using a laser and part of the lower corneal layer is ablated. The cornea is then closed again.
This results in a correction of the degree of curvature of the cornea. This degree of curvature, together with the curvature of the eye lens, determines the amount of light that reaches the retina of the eye. The incidence of light on a certain point of the retina enables sharp vision.
If the curvature of the cornea is too strong or irregular, the light does not hit the right point of the retina and a fixed object cannot be seen sharply. However, there are risks associated with LASIK surgery. For example, infections, scarring or instability of the cornea may occur.
In addition, it is possible that there is a false correction and the cornea has an unsuitable degree of curvature even after the operation. All these factors can lead to blurred vision. Cataract, also called cataract, is a clouding of the lens of the eye.
This clouding can be corrected by a surgical procedure in which the core of the lens or the entire lens is replaced. However, there are also risks associated with this operation. Approximately 30% of patients experience a so-called after-star, i.e. the patient’s vision becomes cloudy again after cataract surgery.
This is caused by a kind of scar that forms at the site where the new lens core was inserted. In rare cases, the retina detaches. As with any surgery, cataract surgery can also cause an infection, which in turn can lead to blurred vision.
Diabetes can be accompanied by many concomitant diseases, especially if the blood sugar level is not optimally adjusted over a long period of time. A common one is diabetic retinopathy. The increased sugar content in the blood leads to vascular damage via various mechanisms.
If this vascular damage occurs in the area of the retina, where the vessels are particularly fine, this leads to pathological deformities of the retina and its blood vessels. These anomalies can remain asymptomatic for a long time, but later lead to a deterioration of vision up to blindness.It is therefore of particular importance that diabetics adjust their blood sugar levels optimally and have regular ophthalmological examinations. The thyroid gland regulates many functions of the body by releasing hormones.
If the thyroid gland is diseased, such as over- or under-functioning, many metabolic disorders can lead to visual disturbances such as blurred vision. In this case, the visual disturbance is often accompanied by other symptoms, which should be assessed and classified by the physician through detailed questioning of the affected person. One form of hyperthyroidism is Graves’ disease.
It is accompanied by an enlargement of the thyroid gland, tachycardia and exophthalmus. Exophthalmus is the excessive discharge of the eyeball from the orbit. This can then lead to impaired eye mobility, which in turn can result in impaired vision.
Stress can be a factor contributing to the occurrence of blurred vision. Stress can lead to an imbalance in the functions of the body. If there are no phases of relaxation and recovery, numerous malfunctions can occur, which can also result in blurred vision.
For example, tension often occurs in stressful phases of life, which, as described above, can have a negative effect on vision. The tear fluid keeps the eye constantly moist. It has the task of rinsing and disinfecting the eye.
It also contributes to the formation of a smooth and even surface of the eye and supplies the cornea with nutrients. If there is not enough tear fluid, this can lead to a rough surface of the eye. As a result, the conditions for light incidence and image processing are no longer optimal and you may have blurred vision.
Blurred vision when wearing contact lenses can have various causes. For one thing, the strength of the contact lenses may not match the person’s visual acuity. Another reason may be irritation of the eye by the contact lenses.
Especially when using hard contact lenses, this can lead to irritation of the outer eye. This is then accompanied by a foreign body sensation and possibly itching and tears in the eye. Pregnancy is accompanied by many hormonal changes that can also affect the eye.
The composition of the tear fluid can change, which can cause dry eyes. Also the visual acuity can change during pregnancy due to the storage of fluid in, for example, the lens. These changes are usually not threatening and regress after pregnancy. However, if there is a sudden, serious deterioration in vision, this should be clarified immediately. The cause can then be a so-called pre-eclampsia, for example, which is accompanied by increased blood pressure, which can lead to visual problems and is considered a serious complication for mother and child.
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