The windscreen masked down to a round hole in the middle and the windows darkened - who would drive so voluntarily? Some people do it without knowing it. Because not everyone who has passed the official eye test looks good. This measures only a tiny central point of visual acuity. However, the essential component of vision is also the peripheral vision, that is, what is perceived out of the corner of the eye around the focus. This so-called field of vision may be limited by a variety of pathological causes, from glaucoma to stroke, without the patient knowing of his illness.
Danger of accident due to limited visibility
For a child running across the street from the side, such a reduced view becomes a mortal danger: if the driver first notices the child when he is in focus, it may already be too late for braking. "The regular ophthalmological control prevents such horror scenarios, " said Prof. Dieter Friedburg, head of the department "Ophthalmic Optics" in the Professional Association of Ophthalmologists (BVA). "Because in the study of the ability to drive, we always examine the peripheral vision of our patients, we can diagnose the causes of a limited visual field, initiate appropriate therapy and thus avert serious disease outcomes."
Tumor or stroke - readable in the eye
The failure of parts of the visual field can cause various diseases. In many cases, the patient does not realize at all that parts of his visual field are restricted, since central visual acuity is not impaired. Therefore, the targeted control is even more important, because failures of the visual field can also point to other illnesses. In the ophthalmological practice it happens again and again that the specialist diagnoses a stroke due to a limited peripheral vision. Symptoms of stroke, such as paralysis, may decline, but the danger is often not yet eliminated. Using visual field defects in typical form, the ophthalmologist can determine that the problem has not yet been resolved and refer the patient to the neurologist or family doctor for treatment.
Also pituitary tumors, usually benign growths in the brain area, are often discovered by the ophthalmologist, they bring a very characteristic limitation of the peripheral vision with it. Affected then look like blinders - for motorists, this can lead to disaster. If such a tumor goes undetected, it leads to blindness in the worst case. Depending on the type of visual field loss, the ophthalmologist can even detect where the brain is disturbed.
Rescue from blindness by regular eye check
It is particularly bad when the peripheral vision is limited due to glaucoma. Also known as a green star, this disease of the optic nerve affects around 800, 000 people in Germany. Prof. Friedburg therefore warns for early detection: "If glaucoma is recognized too late, it may have already destroyed too many cells of the optic nerve and the retina.The limitation of the visual field in glaucoma can not be reversed - so the patient's view can be do not restore. " A regular check-up with an optic nerve check and an intraocular pressure check with the ophthalmologist prevents glaucoma from getting that far.
A rarer cause of such visual field defects are so-called degenerative diseases of the retina, such as retinitis pigmentosa. Dr. Uwe Kraffel, 1st Chairman of the BVA, on the importance of the regular examination: "To assess the eyesight is also essential to examine the visual field, a simple eye test at the optometrist is not enough because the comprehensive diagnosis of the ophthalmologist is not only on the good view of the patient, but also on possible general and severe eye diseases. " Source: Professional Association of Ophthalmologists Germany eV (BVA)