What Causes Peripheral Vision Loss, or Tunnel Vision?

Several underlying health conditions may be the cause of PVL. Migraine causes temporary PVL, while other conditions put you at risk for permanent PVL. You may experience PVL over time, with only some of your side vision affected at first.

Some causes of PVL include:

Glaucoma

This eye condition causes pressure in the eye because of fluid buildup and directly impacts peripheral vision. If it’s left untreated, it can affect the optic nerve and cause irreversible blindness.

Retinitis pigmentosa

This inherited condition will gradually cause PVL as well as affect night vision and even central vision as your retina deteriorates. There’s no cure for this rare condition, but you may be able to plan for the vision loss if it’s diagnosed early.

Scotoma

If your retina is damaged, you may develop a blind spot in your vision, known as a scotoma. This can be caused by glaucoma, inflammation, and other eye conditions like macular degeneration.

Stroke

A stroke can cause loss of vision on one side of each eye permanently. This is because a stroke damages one side of the brain. This is a neurological type of vision loss, as your eyes are still in working order, but your brain can’t process what you see. A stroke may also result in a scotoma.

Diabetic retinopathy

This condition occurs if you have diabetes and experience damage to your retina caused by high blood sugar that inflames or restricts your blood vessels in the eye.

Migraine

Migraine is a type of headache that can result in vision changes. The American Migraine Foundation states that 25 to 30 percent of those with migraine experience visual changes during a migraine with an aura. This may include temporary PVL.

PVL may be temporary or permanent, depending on the condition causing the loss of vision.

Permanent PVL can be caused by:

• glaucoma
• retinitis pigmentosa
• scotoma
• stroke
• diabetic retinopathy

Temporary PVL can occur with:

• migraine

You may experience a range of severity of PVL. Some conditions will begin to distort the outermost angles of your vision and work inward over time.

You may begin to notice PVL once you can no longer see 40 degrees or more from your side vision. If you can’t see beyond 20 degrees of your vision field, you may be considered legally blind.

You may notice PVL gradually or all of a sudden, depending on its cause. Some symptoms of PVL may include:

• bumping into objects
• falling
• difficulty navigating crowded spaces like in shopping centers or at events
• being unable to see well in the dark, also known as night blindness
• having trouble driving at night and even during the day

You may have PVL in just one eye or in both eyes. You should discuss your symptoms with a doctor to determine whether you can drive safely or engage in other high-risk activities with PVL.

Here are other symptoms you may experience with PVL if you have one of the following conditions:

• Glaucoma. You may not notice symptoms of this condition, so it’s essential that you see your doctor regularly. Glaucoma will affect the very edges of your vision first.
• Retinitis pigmentosa. The first symptom you might experience from this condition is difficulty seeing at night. The condition will then affect the outermost angles of your vision and then come inward toward your central vision.
• Scotoma. The major symptom of this condition is noticing a blind spot at a certain angle in your vision. It can impact either central or peripheral vision.
• Stroke. You may not even realize you have PVL on one side of your vision right away. You may first notice it if you glance at a mirror and see only one side of your face.
• Migraine. Vision changes generally occur for 10 to 30 minutes in both eyes during a migraine attack.
• Diabetic retinopathy. Symptoms of this condition include having blurred vision, experiencing blank spots in your field of sight, and having difficulty seeing at night, among others. This condition affects both eyes.

In many cases of PVL, your side vision may not be restored. It’s important to see an eye doctor regularly to monitor and diagnose conditions that may affect your PVL permanently.

Your doctor may be able to suggest certain lifestyle changes you can make if you have PVL. This includes being trained on how to visually scan the world around you using the vision you do have.

Some current research examines the use of glasses featuring a prism that can augment your side vision if you have PVL.

Your doctor will recommend treatments for the conditions causing PVL and to help slow vision loss:

• Glaucoma. You may have to use eye drops or another form of medication, as well as undergo surgery to prevent glaucoma from worsening.
• Retinitis pigmentosa. There is no cure or treatment for this condition, but your doctor may recommend assistive devices as your vision gets worse, or taking vitamin A to slow the loss of vision.
• Scotoma. You may consider adding bright lights to rooms and magnifying your screen or printed reading materials to help you see better.
• Stroke. It may not be possible to treat the PVL caused by this condition, but your doctor may recommend visual screening and utilizing prisms on glasses to help you navigate.
• Migraine. Migraine is treated differently from person to person. You may use a combination of medications to use during a migraine attack and to prevent them. Your doctor may also recommend certain lifestyle modifications to prevent their onset.
• Diabetic retinopathy. Treatment for this condition may include medications to control your blood sugar and blood pressure and to slow the development of vision loss. Surgery may also be an option.

You should see a doctor right away if you notice PVL. You should also see an eye doctor regularly to monitor for potential conditions that may impact your vision. If you catch a condition in its early stages, your doctor may be able to prevent significant vision loss.

The American Academy of Ophthalmology recommends that you visit a doctor by the age of 40 to get tested for various eye conditions to prevent the development of unwanted symptoms like PVL.

PVL and other forms of vision loss may impact your day-to-day life in significant ways over time. Keeping a positive outlook and finding resources to help you are great first steps in coping with vision loss.

Here are some other ways you can live with vision loss:

• Talk to your doctor about ways to treat and adapt to life with PVL.
• Discuss your condition with family and friends and allow them to be a support for you.
• Practice self-care by eating a healthy diet, exercising regularly, and engaging in activities that lower stress to keep up your overall physical and mental health.
• Modify your home to help you navigate and prevent falls: You can install grab bars in areas where you may be more at risk of falling and remove clutter and other objects that may get in your way when walking around.
• Add extra light to dimly lit rooms.
• See a counselor or join a peer-support group to discuss life with vision loss.

Several conditions can cause PVL, and it’s important to get preventive eye screenings regularly to prevent loss of vision. If you ignore symptoms, you may experience more vision loss as time goes by.

See a doctor to discuss your symptoms. Getting preventive or early treatment may help you control further complications from PVL. If you have a condition that has caused permanent PVL, talk to your doctor about ways you can cope with your vision loss.