Phosphenes are the perception of flashes, sparks, or patterns of light without actual light entering the eye. They arise from stimulation of the retina or visual pathways.
Causes
Triggers can be mechanical, electrical, or metabolic.
- Rubbing or pressing on closed eyes mechanically stimulates retinal cells
- Retinal traction or tears causing brief, peripheral flashes of light
- Migraine aura or occipital seizures producing complex visual patterns
- Side effects of certain medications or visual pathway disease
When to seek help
Some phosphenes are benign, others need urgent review.
- Immediate assessment for new flashes with floaters or a curtain in vision to exclude retinal tear or detachment
- Neurological review if phosphenes accompany headache, weakness, or altered consciousness
- Routine eye check if symptoms are mild and longstanding but unexplained
- Documentation of frequency, duration, and associated factors aids diagnosis
