If you’ve ever been hit on your head and “seen stars,” those lights weren’t in your imagination.

Streaks or specks of light in your vision are described as flashes. They can happen when you bang your head or get hit in the eye. They can also appear in your vision because your retina is being pulled by the gel in your eyeball.

Flashes should be taken seriously if you’re seeing them frequently.

There are several causes of seeing stars in your vision. One is the result of a blow to your head. This type of injury can scatter nerve signals in your brain and affect your vision temporarily.

Something else may be happening inside the eye besides injury. When you see stars inside the eye, you may be experiencing what’s called an entoptic phenomenon. There are various causes for these visual events.

In some cases, pregnant women may experience an increased number of floaters, possibly due to high blood pressure or elevated glucose levels. Floaters are tiny, cloudy spots that seem to drift in and out of your field of vision. They’re actually little clumps of vitreous gel floating inside your eye. Sometimes they can be caused by other conditions, including:

  • tears or holes on the retina
  • poorly controlled blood pressure
  • diabetic retinopathy
  • blood clots in the retinal blood vessels, which are blood vessels that carry blood to your retina
  • viral infections in your eye
  • normal complications from eye surgery
  • autoimmune diseases like lupus
  • ocular tumors

Occipital lobe

Your brain is made up of four main sections, or lobes. The occipital lobe is in the back of your brain. It’s responsible for interpreting the nerve signals from your eye.

If you’re looking at a tree, your retina converts that image of a tree into nerve signals that travel from the retina through the optical nerve to the brain. Your occipital lobe processes those signals so your brain recognizes that image as a tree.

If you get hit on the head, the tissue in your occipital lobe gets shaken up. Brain cells then send out random electrical impulses, which your brain interprets as flashes of light that may seem like stars.

Anatomy of the eye

It doesn’t always take a bump on the head to get stars into your field of vision. To understand why, it helps to know a little more about the anatomy of your eye.

The retina is a thin tissue layer at the back of your eye that is light sensitive. The part of your eyeball directly in front of the retina contains vitreous, a gel-like substance that helps your eye keep its shape. There are also tiny, very thin fibers in the vitreous. When these fibers pull on your retina or the gel rubs against your retina, you may see stars.

If your retina gets pulled too hard or moves out of its usual position, the result can be a retinal detachment. This can cause you to see stars. It can also cause you to lose all or part of your vision in that eye. A detached retina can often be treated successfully with surgery.

Migraine headaches

One other cause of stars in your vision is a migraine headache. Not everyone who has migraines sees stars or colorful lights (which are also known as aura), but many do.

If you see stars or jagged streaks of light but don’t have a headache, you may have ocular migraines. These are treated by ophthalmologists or optometrists, doctors specializing in eye health.

Traditional migraine headaches, as well as a blow to the head, can give you a lingering pain in your head to go with your starry visions.

If a retinal detachment is to blame, you may see floaters along with flashes.

Floaters don’t always indicate a problem with your eye health. If you notice that you’re seeing them more often, tell your eye doctor.

A detached retina can also make it seem as though a curtain is being drawn over your vision in the affected eye. If you experience this, it’s an emergency, and you must see an eye doctor immediately.

If you see occasional stars, but have no other symptoms or vision problems, you’re probably fine. But at your next eye appointment, tell your doctor how often you see flashes or floaters. If you start to see more flashes of light, call your eye doctor right away. Also report if you’ve had any injuries, such as a fall or something striking your head.

As you get older, your risk of retina problems and vision impairment increases. You tend to see more floaters as you age too.

Your odds of having a detached retina in one eye go up if you’ve had a detached retina in your other eye. A family history of detached retinas also increases the chances you’ll have the same problem.

Any type of eye injury makes it more likely that you’ll see stars and have problems with your retina. That’s why it’s important to wear protective eyewear when working with tools or playing sports, such as racquetball. Contact sports, such as football or soccer, boost your odds of getting hit on the head and shaking up your occipital lobe.

See your doctor if you’ve had a serious blow to the head that produces stars in your vision, confusion, and a headache. That means you’ve had a concussion. Even a mild concussion should be evaluated by a doctor.

If you’ve hit your head, your doctor will likely test your:

  • vision
  • hearing
  • reflexes
  • balance
  • coordination

You’ll also be asked several questions to test your cognitive health. A CT scan is also part of a routine concussion check.

If you haven’t had an injury to your head or eyes, but you start seeing flashes regularly or have other vision problems, see an ophthalmologist or optometrist as soon as possible.

A trip to an eye doctor for a possible retina problem will include a thorough examination of your eyes. Your pupils will be dilated. A detached retina and other eye conditions are often diagnosed easily with a thorough clinical exam. An ultrasound of your eye may also be helpful.

You likely don’t need to visit your doctor if you see an occasional flash, but you should still mention it at your next regularly scheduled appointment.

Treating a concussion usually includes rest and possibly acetaminophen (Tylenol). Other types of pain relievers should be avoided unless your doctor recommends one of them.

While you’re recovering, your doctor may advise you to avoid TV, video games, and bright lights. Relaxing activities that don’t require a lot of mental concentration may also be helpful.

If you have a detached retina or a tear in your retina, you’ll need surgery. Surgery for these conditions often uses lasers or cryopexy, which is a freeze therapy. Sometimes a follow-up procedure is needed to complete the repair of a detached retina.

Occasional flashes may be a nuisance, but they aren’t always a sign that something is wrong, although it’s best you discuss them with your eye doctor. If they’re caused by retina problems, surgery can usually help restore clear vision and eliminate flashes. You may need to take extra precautions to avoid activities or situations in which an eye or head injury is possible. But none of these should hurt your quality of life.

If you’re seeing the flashes after a blow to your head, and the injury was minor and the stars were temporary, you shouldn’t have any lingering problems.

If you’ve received multiple concussions, you may be at a higher risk of brain health issues, such as chronic traumatic encephalopathy. You may need to stop playing football or other sports with a high risk of concussions to improve the outlook for your brain health.

If you see stars in your vision, be sure to tell your doctor. The sooner an eye problem is diagnosed, the greater the chances of preserving your eyesight.

Pay attention to other changes in your vision. Some eye problems develop slowly, so it may take a while for you to notice any changes.

Here are some tips for eye health:

  • Test your vision in each eye at home. If your eyesight isn’t clear in both eyes, make a doctor’s appointment right away.
  • Plan to have a thorough eye exam once a year unless otherwise directed by your doctor.
  • Use protective eyewear for any activity that poses a risk to your eye health. This includes working with power tools, playing high-speed sports, and working with chemicals.

Losing your vision is a life-changing event. Seeing stars may be an early sign of a bigger problem, so take this symptom seriously and have your eyes checked soon.