How it manifests itself and how it differs from a gradual decline
Gradual deterioration of vision over months and years is usually due to nearsightedness, cataracts or age-related changes and requires a routine visit. A sharp decrease is considered to be a decrease that a person notices at a specific moment: in the morning after sleep, while reading, or suddenly in the middle of the day. Sometimes the problem is discovered by chance when a person closes the good eye. The nature of the disturbances tells the doctor the level of damage: clouding of the transparent media of the eye, disease of the retina, optic nerve or visual centers of the brain.
- Veil or fog before the eye
- Dark spot in the center of the field of view
- “Blind” or loss of part of the field of vision
- Curvature of straight lines and changes in the size of objects
- Brief loss of vision lasting a few minutes
- Doubling of objects
Possible reasons
Causes are divided into ocular and non-ocular. The first include circulatory disorders in the retina, retinal detachment, vitreous hemorrhage, acute attack of angle-closure glaucoma, inflammation of the cornea or choroid, and the wet form of age-related macular degeneration. The second includes optic neuritis, ischemic neuropathy, stroke in the occipital region of the brain, tumors and increased intracranial pressure. Temporary blurred vision occurs with sudden fluctuations in blood sugar levels and migraines with aura.
- Occlusion of the central retinal artery or vein
- Retinal detachment
- Acute attack of glaucoma
- Vitreous hemorrhage, including in diabetes
- Optic neuritis
- Ischemic optic neuropathy, giant cell arteritis
- Stroke and transient ischemic attack
What to do if you suddenly lose vision
You shouldn’t put random drops in, warm your eyes, or wait until the morning. If vision suddenly disappears, especially in one eye and without pain, you need to see an ophthalmologist or an on-duty eye hospital as soon as possible. If combined with numbness, weakness in the limbs, speech impairment or severe headache, call an ambulance on 103: it could be a stroke. Even if vision is restored within a few minutes, the episode requires examination, as it may precede a stroke.
- Note the time of onset of symptoms
- Check each eye individually
- Don't drive
- Bring your glasses and a list of medications you are taking with you.
- Tell your doctor about diabetes, hypertension, heart rhythm disturbances
Diagnostics
The ophthalmologist checks the visual acuity of each eye, measures intraocular pressure, examines the anterior segment of the eye and the fundus with a dilated pupil. Optical coherence tomography allows you to see swelling and detachment of the retina, changes in the macula. Perimetry reveals loss of visual fields, characteristic of diseases of the optic nerve and brain. If the internal structures of the eye are not visible due to hemorrhage, an ultrasound examination is performed. If a neurological cause is suspected, an MRI of the brain and orbits is prescribed; in the elderly, tests for inflammatory markers are prescribed.
- Visometry and tonometry
- Biomicroscopy and ophthalmoscopy with a wide pupil
- Optical coherence tomography of the retina and optic nerve head
- Computer perimetry
- Ultrasound of the eye (B-scan)
- MRI of the brain and orbits, duplex study of neck vessels
- ESR and C-reactive protein in patients over 50 years of age
Treatment and prevention
Treatment depends entirely on the cause and is prescribed by a doctor. In case of retinal detachment, laser or surgical operation is necessary; in case of an acute attack of glaucoma, urgent pressure reduction with drugs and laser iridotomy is necessary. Wet macular degeneration and retinal edema are treated with intraocular injections, inflammation of the optic nerve is treated together with a neurologist. Vascular disorders require searching for the source of blood clots and correcting risk factors. Prevention consists of monitoring blood pressure and sugar and regular fundus examinations.
- Monitoring blood pressure and sugar levels
- Fundus examination once a year for diabetes and high myopia
- Regular measurement of intraocular pressure after 40 years
- Quitting smoking
- Eye protection during traumatic work and sports
- Call immediately if symptoms recur
