Seeing stars can be problematic. In most cases, there is nothing to worry about. But in some cases, it could mean that something is wrong with your vision or your eye health.
This phenomenon is known as photopsy .
Symptoms of photopsia include vision:
- Streaks of light
- Multicolored rings
- Flashing lights
These visual impairments are usually the result of temporary physical pressure on the eyes, such as rubbing the eyes or violently sneezing.
If you experience photopsy frequently or for long periods, see your doctor. An optometrist or ophthalmologist can perform a complete eye exam to determine the cause.
This article looks at photopsy and five possible medical causes of stars.
How does photopsy occur?
When a photopsy is performed, the retina is stimulated by invisible light. These artificial flashes of light are known as phosphenes .
Phosphenes can be caused by pressure in the eyes or by stimulation of certain neurons in the eye or brain.
The most common cause of phosphenes is pressure in the eyes. This could be rubbing your eyes, sneezing, or hitting your head.
Photopsy can also occur due to illness. For example, low blood pressure, eye injuries, eye or brain diseases, or migraines can cause you to see stars or flashes of light.
Photopsia (seeing stars or flashes of light) occurs when the retina is stimulated. This may be due to pressure, such as rubbing your eyes. It could also be a sign of a health problem.
Pressure-induced phosphenes can persist for a few seconds. For example, you can see stars when you rub your eyes, sneeze, cough, strain, or vomit.
When phosphenes persist for more than a few seconds or recur frequently, this could be a sign of a more serious problem and you should see an eye doctor immediately.
Phosphenes can be due to pressure inside the eye or brain.
Possible reasons include:
- Blood vessel abnormality
- Trauma, damage
- Thyroid disease
Posterior vitreous detachment
Posterior vitreous detachment (PVD) is a common condition caused by aging.
The vitreous humor is a jelly-like substance that fills the center of the eye and shapes the eyeball. It is attached to the retina. With normal aging, the vitreous becomes less hard and the retina can stretch in the process.
If the pulling force becomes strong enough, the vitreous humor can detach from the retina. When this happens, a person can see floating objects, flashes of light, or stars. Photopsy caused by PVD usually appears as streaks of light, usually next to the visual field, also known as peripheral vision.
PVD can cause retinal tears, holes, and detachment, so it should be followed by proper consultation with an ophthalmologist, even if it is a normal part of the aging process. Your healthcare professional will monitor you for signs of retinal detachment, holes, and tears early in the first few weeks of PVS.
Due to retinal problems, you may see stars, flashes, or streaks of light. Retinal detachment is one of those conditions. This occurs when the retina deviates from its normal position in the eye.
- Flashes of light in one or both eyes
- A dark shadow that appears to be a curtain blocking part of your view.
- Augmented floaters, which are small dark spots or wavy lines that float in your field of vision.
Symptoms of retinal detachment appear quickly. If you experience these symptoms, see an ophthalmologist or go to the emergency room.
Retinal detachment is a medical emergency.
If the retinal detachment is not treated in time, more damage can occur. Also, delaying treatment increases the risk of permanent vision loss or blindness.
Other retinal diseases that affect the function of the eye can cause gradual loss of vision. This can cause the effect of seeing the stars.
Certain medications can also alter the function of the retina by producing phosphenes. One such drug is Corlanor (ivabradine) , which is used to treat tachycardia (heart palpitations).
Visualization and explanation of 5 types of migraine auras
Some migraines can have a visual aura without headaches. This is called an ocular migraine. The aura can affect one or both eyes and can look like this:
- Prismatic colors like a rainbow
- Flashes of light
- Zigzag lines
- Blind spots
If the flare-ups are followed by a headache, the attack is diagnosed as a migraine. However, if these flashes or lines of light occur without a headache, it is often called a headache-free migraine.
Impaired visual function in the brain.
Although less common, phosphenes can occur due to dysfunction of the visual areas of the brain. This can happen as a result of a lack of blood flow or damage to the brain.
Orthostatic hypotension, also called postural hypotension , is a sudden drop in blood pressure. This usually occurs when a person who already has high or low blood pressure quickly transitions from a lying or sitting position to a standing position.
This drop in blood supply can briefly interrupt the brain, causing flashing lights or similar phenomena for a few seconds.
The phenomenon of stargazing is known as photopsy. The individual flashes of light are called phosphenes.
Phosphenes are produced when pressure on the eye stimulates the retina. The retina is the structure of the eye that regulates light. The pressure can be caused by an external force, such as rubbing the eyes, an internal structural problem, or inflammation.
Photopsia can also occur with migraines, changes in blood pressure, insufficient blood flow to the brain, or damage to the brain.
Photopsy is usually harmless. However, if you see frequent flashes of light, it could be a warning sign of something more serious. If you experience this, see your doctor immediately.