Floaters and flashes in the eyes

Floaters are small shapes that drift through your vision. They may look like dots, threads, cobwebs, rings, or clouds. They often move when your eyes move and dart away when you try to look directly at them.

Flashes are brief lights that do not come from your surroundings, such as sparks, lightning streaks, flickering, or shimmering shapes.

Many floaters result from ordinary changes in the clear gel inside the eye, called the vitreous. However, sudden new floaters or flashes can mean that the retina—the light-sensitive layer at the back of the eye—is being pulled or has torn. A prompt eye examination is the only safe way to tell the difference.

Floaters are easiest to notice against a bright, plain background, such as a white wall, clear sky, or computer screen. They move with your gaze and may continue drifting after your eye stops.

Flashes caused by changes inside the eye are often brief, near the edge of vision, and more noticeable in dim light or when you move your eyes.

Migraine-related symptoms may involve shimmering zigzags, flashing patterns, or a growing blurred area. They usually affect the same side of the visual field in both eyes, although they may seem to involve only one eye. A headache may follow, but aura can occur without one.

Common causes include:

• Age-related vitreous changes: The vitreous becomes more liquid over time. Clumps or strands cast shadows on the retina, creating floaters.
• Posterior vitreous detachment: The vitreous separates from the retina with age, potentially causing a large floater, smaller specks, and flashes. It is not retinal detachment, but it can sometimes tear the retina.
• Migraine aura: Temporary changes in brain activity produce flashing or shimmering patterns, with or without headache.

Less common causes include inflammation, bleeding inside the eye, injury, or changes after eye surgery. People who are very short-sighted may develop floaters earlier.

A retinal tear or retinal detachment is less common but urgent. Retinal detachment means the retina has lifted away from its supporting tissue and is often painless.

Arrange a same-day urgent eye assessment if:

• Floaters or flashes suddenly appear for the first time
• The number of floaters suddenly increases
• You see a dark curtain, veil, or shadow
• Part of your vision is missing, blurred, or reduced
• Symptoms start after an eye injury or recent eye operation
• New floaters or flashes occur with eye pain or marked redness

Do not wait for symptoms to settle. Contact an optometrist or ophthalmologist who can examine the retina through a dilated pupil. If same-day eye care is unavailable, use an urgent care or emergency service.

Call emergency services for sudden vision trouble with weakness, facial drooping, difficulty speaking, severe imbalance, confusion, or an unusually severe headache. These can indicate a problem affecting the brain.

Book a routine appointment if stable, longstanding floaters interfere with reading, driving, or daily activities, or if you remain concerned about a visual symptom.

An eye professional will ask when symptoms began, whether they affect one or both eyes, and whether you have a shadow or vision loss. They may also ask about short-sightedness, migraine, injuries, surgery, and previous retinal problems.

The main test is a dilated eye examination. Drops widen the pupils so the retina can be checked for pulling, holes, tears, bleeding, or detachment. The drops can temporarily blur vision and increase light sensitivity, so bring sunglasses and arrange help travelling home if needed.

If blood or another problem blocks the view of the retina, an eye ultrasound may be needed. Other imaging depends on the examination findings.

Ordinary vitreous floaters often need no treatment. Many become less noticeable as they settle or the brain learns to ignore them. Moving your eyes may shift a floater temporarily, but exercises do not remove it.

No proven home treatment or supplement dissolves vitreous floaters. Procedures to remove or break up floaters may be considered when they severely affect daily life, but they carry risks and are not routinely needed.

A retinal tear may be sealed with laser or freezing treatment to reduce the risk of detachment. A detached retina usually requires surgery. Inflammation, bleeding, and migraine symptoms are treated according to their cause.

Do not rely on self-care for sudden symptoms. Covering one eye and then the other may help identify which eye is affected, but it must not delay urgent assessment.

Migraine aura often clears within an hour. Flashes from vitreous separation commonly become less frequent, while some floaters remain visible for months or longer.

Your eye professional may recommend follow-up even after the first examination. Seek urgent reassessment if floaters increase, flashes return or worsen, or a shadow or vision loss develops—even after a reassuring examination.

Are floaters normal with age?

They are common as the vitreous changes with age. However, sudden new floaters need prompt assessment because symptoms alone cannot rule out a retinal tear.

Can tiredness or screen use cause floaters?

Bright screens and pale backgrounds can make existing floaters easier to see. Screen use and tiredness do not usually create vitreous floaters.

How can I tell migraine aura from a retinal problem?

Migraine aura often produces an expanding or moving pattern in both eyes’ visual fields and then clears. Retinal symptoms are often in one eye and may include new floaters, edge-of-vision flashes, or a dark shadow. Because these patterns can overlap, new or uncertain symptoms should be assessed rather than self-diagnosed.

Can rubbing my eyes make flashes appear?

Pressure on the eye can briefly stimulate the retina and produce light sensations. Repeated, spontaneous, or new flashes should not be assumed to come from rubbing.