Tunnel vision, or peripheral vision loss (PVL), is a result of the loss of peripheral sight, or side vision. A person with PVL can only see what is directly in front of them. This can occur due to conditions that affect the eye or other health conditions.
A person should seek medical help as soon as possible to help prevent permanent vision loss.
This article will discuss what PVL is and what can cause it. It will also look at the treatment options available and when to seek medical help.
PVL refers to the loss of peripheral sight, which is the sight that lies outside of a person’s direct line of vision.
This means that the eyes can clearly see what is straight in front of them but that there may be gaps in a person’s side vision.
It can be temporary or permanent, depending on the cause.
A person might notice that the outer edges of their vision are blurry or dark but that the center of their vision is clear. People may describe severe PVL as looking through a tunnel, hence the term “tunnel vision.”
Depending on the cause, a person can experience PVL in one or both eyes.
They may also find that they:
- have difficulty navigating a crowd
- bump into objects
- fall over
Other symptoms will depend on what is causing a person to experience PVL. The following sections will look at potential causes in more detail.
Migraine can cause a range of visual disturbances, including:
- tunnel vision
- complete loss of vision
- loss of vision on one side
According to the American Migraine Foundation, these visual disturbances are temporary, typically lasting for around 20–60 minutes.
A person may also experience sensory changes and speech and language problems. If the symptoms are immediate and last for longer than 60 minutes or do not resolve entirely, immediate medical help is necessary.
During a migraine episode, a person may find it helpful to sleep or to lie in a dark room. A person can also take pain relief medication such as acetaminophen, ibuprofen, or aspirin.
Retinitis pigmentosa (RP) refers to a group of conditions that affect the retina. It is genetic.
According to the American Academy of Ophthalmology (AAO), RP alters how the retina responds to light. This can make it difficult for a person to see.
Alongside a gradual loss of peripheral vision, other symptoms may include:
- Loss of night vision: This means that a person cannot see anything when it is dark. Their vision may be normal throughout the day but take longer to adjust to the darkness. A person may also find it difficult to see clearly in dim lighting.
- Loss of central vision: A person may also have difficulty with their central vision.
- Difficulties with color vision: A person may have difficulty seeing colors.
The AAO state that there is no specific treatment for RP. Supplementation with antioxidants such as vitamin A or omega-3 may be helpful in slowing progression.
There are also certain services and devices that can help those with RP carry out daily activities.
People can talk with an ophthalmologist for further advice and treatment suggestions.
According to the National Eye Institute (NEI), glaucoma is a group of conditions that cause vision loss by damaging the optic nerve. The optic nerve is located at the back of the eye and is responsible for sending signals to the brain so that it can produce images correctly.
Glaucoma is the buildup of fluid pressure in the eye. There are different types of glaucoma, and the most common is open-angle glaucoma.
In the early stages, glaucoma does not typically cause symptoms. However, a person will slowly lose their peripheral vision — typically the part closest to their nose — over time.
Without treatment, a person can eventually lose their vision entirely. Treatment will not undo any damage that has already occurred, but it can help prevent it from worsening.
Treatment options for glaucoma typically include:
- Medications: Eye drops can lower the pressure in the eye.
- Laser treatment: This helps drain the fluid from the eye, thereby relieving pressure.
- Surgery: This might be an option if medications and laser treatment are ineffective.
Diabetic retinopathy is a condition that can cause vision loss in those who have diabetes.
The NEI note that when a person has too much sugar in their blood, it can damage the retina. This is the part of the eye that detects light and sends the signals to the brain via the optic nerve.
In the early stages, a person will not typically have any symptoms. That said, there may be small changes in vision, such as difficulty seeing faraway objects or difficulty reading.
In the later stages, however — as the blood vessels in the retina begin to bleed into the vitreous — a person may see dark and floating spots. They may also notice streaks that resemble cobwebs.
Some people may require a comprehensive dilated eye exam every 2–4 months.
In the later stages, treatment is necessary to prevent further damage. However, this will not reverse the damage that has already occurred.
Treatment options include:
- Injections: These may include anti-vascular endothelial growth factor drugs or corticosteroids.
- Laser treatment: This is to help reduce the swelling in the retina.
- Surgery: This may be necessary if the retina is bleeding a lot or there are a lot of scars.
According to the British and Irish Orthoptic Society, visual field refers to the entire area of what a person can see when they look directly ahead. This includes a person’s central and peripheral vision.
Visual field loss occurs when a person has lost an area of vision in their visual field. This can occur following a stroke, and it typically affects both eyes.
Whether or not a person recovers their visual field depends on the area of the brain that the stroke affected and how much damage it caused.
Treatment focuses on rehabilitation and may include the use of:
- prism lenses
- eye patches
If PVL occurs due to migraine, the vision loss will likely be temporary. However, many other causes can result in permanent vision loss.
Treatment may not be able to reverse the damage that has already occurred, but it can help prevent the condition from worsening.
If the cause is a stroke, some vision loss can improve without medical intervention. The British and Irish Orthoptic Society note that 50% of those with visual field loss that occurs after a stroke will notice an improvement.
If recovery is likely to happen, it will typically occur within the first 3–6 months following the stroke.
It is important to receive medical advice as soon as symptoms begin to appear. This can reduce the chance of experiencing permanent vision loss.
A person needs emergency medical help if they notice visual disturbances that last for longer than 60 minutes, do not resolve completely, or accompany the following symptoms of a stroke:
- sudden numbness or weakness in the arm, face, or leg
- sudden confusion
- difficulty walking or loss of balance
- sudden and severe headache
An ophthalmologist may need to carry out a comprehensive dilated eye exam to see inside the eye. This will involve administering eye drops that will dilate the pupil. The ophthalmologist will then shine a light into the eye to examine it.
Although a person may not be able to prevent the conditions that cause vision loss, they can try the following tips to help maintain their eye health:
- Visit an eye care professional regularly, if possible.
- Maintain steady blood sugar levels to help reduce the chance of diabetes.
- Eat a healthful diet.
- Maintain a moderate weight.
- Avoid smoking.
- Understand one’s family’s eye health history.
- Wear protective eyewear when necessary.
- Wear sunglasses when outdoors.
- Give one’s eyes a rest from screens.
- Clean the hands and contact lenses correctly to prevent infection.
PVL and vision loss can impact a person’s mental health and daily life.
To help cope with vision loss, a person can talk with a doctor about:
- how to set up their home in order to move around easily
- training on how to use magnifying devices
- how to access visual rehabilitation and other treatment options
A person can also seek help from counselors or join a support group.