Many people occasionally perceive small, translucent shapes, specks, or threads that drift across their vision. This common visual phenomenon, often more noticeable against bright backgrounds, is usually benign. Understanding its causes offers clarity.
What Are Those Tiny Dots?
The most frequent explanation for seeing tiny dots or shapes in your vision involves vitreous floaters. These are small, dark or translucent specks that appear to drift in your field of vision, often described as cobwebs, threads, or rings.
They are not external objects, but rather tiny bits of material within the vitreous humor, the clear, jelly-like substance filling your eye. As light enters the eye, these microscopic fibers or cellular debris cast shadows onto the retina, the light-sensitive tissue at the back of your eye. The brain then interprets these shadows as shapes or dots.
Floaters tend to move as your eyes move, but because they are suspended in the fluid, they often drift slowly even after your eyes stop. They usually dart away when you try to look directly at them.
Most floaters are a normal part of the eye’s aging process. Over time, the vitreous humor can slightly shrink and become more liquid, causing some of its collagen fibers to clump together. They are harmless and do not impair vision, though they can be more noticeable in bright lighting or when looking at a clear sky or white wall.
Is It Visual Snow?
While floaters are discrete shapes that move, another distinct condition known as visual snow presents differently. Visual snow is a neurological phenomenon where individuals perceive constant, diffuse static or “snow” across their entire field of vision. This persistent overlay of tiny, flickering dots resembles the static seen on an untuned analog television.
Unlike floaters, which drift and are often only noticeable in certain conditions, visual snow is a pervasive visual disturbance. The cause of visual snow is believed to be neurological, stemming from a dysfunction in how the brain processes visual information, rather than an issue within the eye itself. This condition can also be accompanied by other visual disturbances, such as afterimages or light sensitivity.
Other Reasons For Seeing Spots
Beyond floaters and visual snow, other conditions can cause individuals to perceive spots or flashes of light. A sudden increase in floaters, especially when accompanied by flashes of light, can signal a more serious underlying issue. These symptoms might indicate a retinal tear or detachment, where the retina pulls away. This can manifest as a sudden shower of new floaters, bright flashes, or a dark shadow or “curtain” encroaching on the field of vision.
Migraine auras are another common cause of temporary visual disturbances. These are not always accompanied by a headache and can involve shimmering, zigzagging lines, or temporary blind spots lasting about 20 to 30 minutes. These visual changes occur due to abnormal electrical activity in the brain’s visual cortex. Additionally, certain systemic health conditions, such as inflammation inside the eye or bleeding due to diabetes or high blood pressure, can lead to spots or blurred vision.
When To Talk To A Doctor
While many instances of seeing tiny dots are benign, certain symptoms warrant prompt evaluation by an eye care professional. Seek immediate medical attention if you experience a sudden onset or a dramatic increase in the number of floaters. New flashes of light accompanying these dots are a significant warning sign requiring urgent assessment.
Another concerning symptom is a dark “curtain” or shadow appearing in any part of your field of vision. This can suggest a serious retinal issue requiring immediate intervention to preserve vision. Any associated eye pain, redness, or a sudden, significant loss of vision necessitates an emergency eye examination.
If you notice any changes in the appearance or pattern of existing floaters, such as becoming larger, darker, or more numerous, consult a doctor. Seek professional advice for any new, persistent, or concerning visual disturbances that interfere with your daily life. Regular comprehensive eye exams are valuable for maintaining overall eye health.