By Efemena Edherigho and Josephine Ochidi
Watching a person who is not able to see, and therefore needs to be led about by another individual or the unfortunate person has to depend on a cane, to tap along the way and know where to step, you would understand why it is absolutely important that you have vision at all times. It is reason to feel indescribable gratitude when you have vision, and also make you more sympathetic towards the blind.
Some people do get stricken with sudden loss of vision, which is a serious medical emergency, and must be treated as quickly as possible. Sudden loss of sight can be a symptom of a serious medical condition, according to a posting on post on the website of the Eye Institute. When a person experiences sudden blindness, he needs to seek medical attention as quickly as possible. Early diagnosis and treatment could help save your sight.
At Next Generation Eye Clinic, where he practices, Dr. David Ehimhen, an optometrist, told Sunday Sun that several conditions have been identified as causes of sudden loss of vision. Some of these conditions are systemic, while some have to do directly with the eyes.
“For instance, if a person has acute glaucoma, it could cause painful loss of vision. Depending on the severity, it could cause total loss of vision. Again, vascular conditions have been established as risk factors for developing sudden loss of vision. How this can happen is like this: if there is occlusion (blockage) of either the retinal artery or retinal vein. This can lead to complete loss of sight,” Ehimhen said.
He explains further: “Again, people suffering from cardiovascular diseases such as heart disease or hypertension or systemic problems like diabetes can also experience sudden loss of vision. Some drugs can also cause partial or total loss of vision. One particular drug is Viagra, which is used to enhance libido in men. The one side effect of Viagra is loss of vision Men who take herbal preparations to enhance sexual performance are also risk and therefore should be careful about they consume to improve sexual performance. These herbal preparations should be taken with absolute caution.
Symptoms of sudden blindness
A sudden loss of vision doesn’t necessarily mean total blindness. Sudden blindness can occur in one eye or both eyes, and the loss of sight can be partial or total.
With total vision loss, the sight in the affected eye (or eyes) is lost completely, so that nothing can be seen with the affected eye. With partial vision loss, some sight may remain in the affected eye.
Sudden vision loss can include a sudden loss of peripheral vision, sudden loss of central vision, or even a sudden blurring of your vision. The sudden appearance of spots within your field of vision could also be a symptom of a more serious condition.
Sudden blindness may only last a short time, such as a few seconds, minutes or hours. However, it could potentially be permanent, especially if not treated quickly.
Causes of sudden vision loss
Sudden loss of vision can occur for a number of reasons. Many underlying problems are very serious, and could potentially be sight threatening or even life-threatening. It’s therefore essential to seek medical help as soon as possible if you experience any sudden loss of sight.
A. Damage to the retina
The retina is the focusing surface at the back of your eye. Any damage to the retina, such as a detached retina or macular hole, is a possible cause of sudden blindness.
A detached retina can cause total loss of vision in the affected eye, or it may only result in partial vision loss, making it seem as if a curtain is blocking part of your vision.
The macula is the central focusing area of the retina at the back of your eye. When a macular hole occurs, it results in a loss of your central vision, while your peripheral or ‘side’ vision remains.
“Several factors are known to cause retinal detachment. These include trauma to the eye, diabetic retinopathy and retinitis, which is inflammation of the retina. Another cause is optic neuritis, which is the inflammation of the optic nerve. Though loss of vision caused by optic neuritis could be reversed, and vision would be restored, but it may not be as it used to be before the loss of vision. However, if it is well treated, vision can be restored in full.
B. Vitreous haemorrhage
Some eye conditions can cause blood to leak into the vitreous ‘gel’ within the eye. This is known as a vitreous haemorrhage. If this occurs, it can block the light, which enters the eye, causing sudden blurred vision, or the sudden appearance of spots within your vision.
Serious medical conditions such as diabetes can cause severe vitreous haemorrhage, whereby blood bleeds into the vitreous humour of the eye. Vitreous hemorrhage could happen because of the severe weakening of the blood vessel of the eye, thereby causing blood to leak through the weakened wall of the vessels into the vitreous humour.
C. Stroke and brain tumor
Other serious medical conditions that can cause sudden blindness include stroke or brain tumour. While these causes are quite rare, it is nonetheless important to seek medical attention as soon as possible.
Treatment for sudden blindness
If you experience sudden blindness or any sudden loss of vision, you need to see an eye specialist straight away. Treatment will depend on the cause of your sudden blindness, but in most cases of sudden blindness, the earlier you are treated, the better your chance of a good outcome.
Ehimhen says that sudden loss of vision is preventable if individuals who have risk factors such as diabetes, hypertension and other cardiovascular conditions, carefully ensure that these conditions are managed adequately with proper medication under the supervision of a doctor. You should always measure blood pressure and blood sugar levels regularly to ensure that they are within the normal ranges.
Once there is glaucoma or angle closure, the person should undergo surgery to open the angle to allow proper drainage of the fluid from the eye.
He also advised that Nigerians should develop the practice of going for regular health checks, which would include checking the state of the eyes so that problems can be discovered early. This would go a long way to help prevent sudden loss of vision.
► Additional material sourced from The Eye Institute