Cataract is characterized by progressive painless vision loss. Most cataracts can't find the cause, sometimes exposed to X-rays or strong sunlight, inflammatory eye diseases, and some drugs (such as corticosteroids) can cause cataracts. In addition, cataract may also be a complication of other diseases, such as diabetes. Cataracts are more common in the elderly, but some newborns are born with cataracts (congenital cataracts).
. symptom
Because the light entering the eye must pass through the lens, if the lens blocks the incident eyeliner, or deflects and diffuses the incident eyeliner, it can affect vision. The extent to which vision is affected depends on the location and density of lens opacity (cataract maturity).
In bright light, the pupil narrows and the light channel of the eye narrows, so cataracts are more likely to block the eyeliner. So many cataract patients have worse vision under strong light. And halo, glare and scattered light appear around the light. When cataract patients go from darkness to bright environment, or read books under bright lights, the blurred vision is particularly obvious. Patients suffering from glaucoma and cataract at the same time, after dropping mydriatic drugs, their vision will also drop significantly.
The opacity behind the lens (posterior posterior subcapsular cataract) also has a serious impact on vision under strong light. Because the posterior pole of the lens is the only way for light, this kind of cataract is more likely to damage vision.
One is nuclear cataract (central opacity of lens), which can be manifested as near vision improvement in the early stage. The reason is that nuclear cataract increases the focusing ability of the lens and can see the near objects more clearly. Most elderly people find it difficult to see nearby objects because of presbyopia. In the early days after suffering from cataract, they were surprised to find that they could read without presbyopia. This phenomenon is often called second vision.
Although cataracts are usually painless, a few patients may have increased intraocular pressure (glaucoma) due to swelling of the lens, which may lead to eye pain symptoms.
Diagnosis and treatment
Doctors can find cataracts through ophthalmoscope (an instrument used to examine the inside of the eyeball). Using slit lamp microscope, doctors can further understand the exact location and degree of lens opacity. Generally speaking, cataract patients can decide when to remove their own cataracts. If patients feel unsafe, uncomfortable or unable to complete their daily work, cataract extraction can be considered. If the patient feels that everything is normal and his life and work have not been affected, he can not have surgery for the time being. Premature surgery has no advantage.
Cataract patients should complete other tests before deciding on surgery. Maybe wearing glasses or contact lenses can increase your eyesight. For cataract patients without glaucoma, the use of mydriatic agents may help to improve their vision. Wearing sunglasses in bright light and replacing direct light with reflected light can also reduce light scattering.
Cataract patients of any age can be treated by surgery, generally without general anesthesia or overnight hospitalization. To remove the turbid lens during operation, it is generally necessary to implant plastic lens or silicone lens (intraocular lens). If no intraocular lens is implanted, the patient needs to wear contact lenses after the operation. If you can't wear contact lenses for some reason, patients can try to wear ordinary glasses, but these ordinary glasses are thick and may distort things.
Cataract surgery is very common and generally safe. In rare cases, postoperative intraocular infection and bleeding will occur, and these complications will seriously affect vision. For the elderly with special circumstances, it is necessary to make arrangements in advance, rest at home for a few days after surgery, and give care. Eye drops or ointment can also be used several weeks after operation to prevent infection, diminish inflammation and promote wound healing. In order to prevent trauma, patients can wear glasses or metal eye mask after operation until the wound is completely healed, and generally need to wear protective eye mask for several weeks. The doctor should check it on the second day after operation, and then check it every 1 ~ 2 weeks within 6 weeks after operation.
Sometimes the posterior capsule of intraocular lens can be turbid within weeks to years after operation, which can be treated by laser.